Conference 7.286::home_work

I did some minor plumbing last night (adding a silcock 2 feet from an
existing run) and when I turned on the water, my tap, a copper tee, leaked!
Nowhere in the small library of DIY books I have is the procedure for fixing
a bad joint described (they all describe how to make the joint in the first
place).

(My analysis is that the line was still draining a few drops every minute
since it was at the bottom of the whole house system and I hadn't drained
the hot water lines and they were back-flowing into the cold water system.
The dripping water apparently spoiled one of the joints of the tee.)

With much difficulty I took the bad joint apart and cleaned it and re-soldered
it and now everything is fine.  But taking the joint apart is rather hard.
(I did manage to get the bad joint of the tee apart without disturbing the
other two joints, but I was not sure that would be the case.)

What is the right way to fix the joint?  Should I have been able to fix
it without taking it apart, just be reheating and applying solder?  Would
the joint have worked without a re-application of the flux?  Any suggestions?

Thanks,
Bob

    Having had the problem on about 80% of my first joints (years of
    experience make this kind of problem go away) I found that if you
    just reheat it, the capillary action will suck that solder right
    in and cure it.
    
    -joet

    It depends upon why there is a bad joint in the first place.  If
    the pipe wasn't coated with solder correctly in the first place
    because of junk on it, you have to take it apart, clean it, and
    coat it.  If that's not the problem, reheating it and adding more
    solder should do it.
    
                                                August G. Reinig

    I agree with .1 and .2.  One thing that I always do when preparing
    copper pipes is to also clean the edge of the fitting.  If this
    edge is clean, the solder will form and nice tight seal with the
    pipe.  

    
    Mark

    
    Well I didn't do the actual soldering, but I did all the cleaning,
    cutting, fitting and fluxing on the 50 or so joints we did Thursday
    night.  I used emerycloth and cleaned about three inches of area
    for each joint (we now have really shiney pipes) and cleaned the
    inside of each elbow or valve as best as possible (and then some).
    
    We installed four valves so that if anything did leak we could easily
    drain just the run we were working on as apposed to the whole system
    again.  
    
    Nothing Leaked!!!  We were proud of ourselves.
    
    					still learning...
    
    						.dave.

    Another common problem is residual water in the system - just when
    you think it's all drained and start to sweat the fitting, a trickle
    of water runs through, turns to steam due to the heat, and blows
    a hole through the still-molten solder.

    Opening ALL the upstairs faucets is the best way of making sure
    there is no trapped water in the system.
    
    Jim    

>     Another common problem is residual water in the system - just when
>     you think it's all drained and start to sweat the fitting, a trickle
>     of water runs through, turns to steam due to the heat, and blows
>     a hole through the still-molten solder.

An annoying drip can be stopped with a plug of bread (a food made
from moistened, usually leavened, flour or meal, kneaded and
baked).  This will absorb the moisture, thus allowing you to
sweat your joint properly and probably turning to toast.  Later,
the rush of water will break up the plug without fouling your
faucets and fictures. 

    You can also buy stuff to shove in the pipe where the joint is
    going to be made and after soldering you heat the pipe in the
    approx place to disvolve it.  Don't remember the name.  Got them
    at SPAGS a few years ago.  Some sort of plastic like coating with
    water inside.  They work great..

    What about sealing up Iron Piping (old) with the new Teflon
    sleeves that are not that tight ??
    
    Lloyd
    

    This advise applies to all do-it-yourself projects:  Spend some of the 
    money you are saving by doing it yourself to buy the right tools!
    I bought a pair of wire-brush tools for 1/2 copper pipe:

	- One is a plastic knob with the brush inside for cleaning the
	  end of the pipe.
	- The other is a round wire brush on a handle for cleaning the
	  inside of the fitting (elbow, tee, valve, etc.)

    At the time, $8.00 or so seemed like a lot for the 'simple' job
    I was doing but I have been complementing myself for my foresight
    ever since.

    I have NEVER (knock on nearest joist) had a leaky sweated joint
    (except when I tried to re-use an old fitting but that's another
    story which leads to PAL's second rule: don't skimp on materials!)
    

    Re: .9
    Agree - those specially designed wire brushes for cleaning fittings
    are the way to go.  After using them you'll NEVER go back to gritcloth
    again except under extreme duress.  I clean the surfaces, then
    immediately spread on a thin layer of soldering paste, even if I'm
    not going to solder the joint for a while.  I think if the joint
    is cleaned and fluxed properly, it's almost impossible to make a
    bad joint.  Contrary to what seems to be the belief of many plumbers,
    you also don't need much solder.  Just enough to fill the joint.
    It doesn't have to pile up on the outside edge.  
    Solder flows toward the heat, so if you need to have solder flow
    uphill, apply heat from the top of the joint.
    
    Also agree - with fittings at Spag's for 27 cents apiece, it's just
    not worth it to try to reuse old ones except in an emergency.

    One small note on fittings. I have found several types which appear
    to be treated as 'all the same' in most stores. They are clearly
    not the same! Look out.  Specifically, two categories
    can be created: 1) Normal 2) High Stress.  You will also find
    these same two categories when buying the actual Copper pipe:
    1) General Purpose 2) Type 'M'.
    
    I use High Stress Pipe and Fittings for ALL applications using
    HOT WATER (incl HEAT). General Purpose for the rest. Seems that most people
    I have talked to agree. The Fittings that sell for 27-cents
    may be GENERAL PURPOSE, not High Stress (Although I found some
    High Stress elbows for 34-cents in one place). Look at the fittings
    carefully. If they look rather 'thin walled' they probably are
    GENERAL PURPOSE. I found some places that argue that it doesn't
    matter, but I would prefer using the right fittings for the right
    application.
    
    Anyone that knows more, please post it here. I am going on what
    I have been able to conclude. I KNOW there are 'Type M' applications
    so it make sense that there are Type M Fittings and Pipe.
    
    By the way, a 10-foot pipe of Type 'M' copper is about TWICE
    the price of GENERAL PURPOSE. Fittings seem to follow this rule.

    
    Mark

    If I remember right, from some type of plumbing book, there are
    3 grades of copper pipe, types K, L, and M (I have no idea why they
    started with that section of the alphabet).  Type K is the heaviest
    duty, but the only place I'ver ever heard of it was in the book.
    Type L is what is normally used for water-supply plumbing.  Type
    M is the lightest duty, and is frequently used for hot-water heating
    applications.
    
    I don't think the temperature of the water has any bearing on which
    type of pipe should be used - it's the pressure the pipe will see
    that matters.  Closed-loop hot water heating systems (not to be
    confused with steam heat) typically operate at 15-20 lbs of water
    pressure.  Town water supplies (especially mine) provide much higher
    pressure than that, so I wouldn't take a chance on Type M for supply
    lines.

    -db

    I think your letters are reversed. Type 'M' is the MOST EXPENSIVE
    pipe I found. Regular (must be type L) is about 1/2 the cost of
    Type M. Therefore Type M must be heavier.
    
    Anyone know for sure?
    
    Mark

    .12 is correct.  There are 3 grades of copper pipe (K, L, M).
    K having the thickest walls.  Type M is good for most exposed
    piping, that is, it is accessible for repair.  Type L is commonly
    used inside walls and above ceilings.  Type L has twice the wall
    thickness of Type M and will not burst if the water inside freezes.
    It is designed to expand, but not burst.
    
    I agree 100%, watch out for thin-wall, cheap fittings !
    
    
    Mark
    

    Why is TYPE M twice the cost of the OTHER pipe? Every Store I
    checked ONLY carried two types, I assume L and M. the one they
    called 'M' is TWICE the cost of the other (L)...
    
    Do they cahrge for THINNER pipe? I don't think so.
    
    Mark
    

    I've always noticed type L to cost more than type M of the same
    diameter.  I believe although I'm not sure, that type L pipe has
    blue lettering and/or stripes on it and type M has red lettering
    on it.  This might help you identify the pipe you're looking at.
    
    -willie
    

    I found the book I referred to in .12 - it's called Rockwell
    Do-It-Yourself Plumbing Guide.  (still has the Spags price sticker
    on it).  To quote:
    
    "There are commercially five grades of copper pipe: Type K, both
    hard and soft, is the heaviest and used generally in commercial
    work.  Type L, both hard and soft, is lighter than K and is popular
    in residential water lines.  Type M is made in hard only and is
    used for light residential lines. (Codes should be checked before
    installing Type M)"
    
    It also explains that "hard" tubing refers to rigid tubing (typically
    found in 10' lengths) and "soft" tubing (flexible) is sold in coils.

    RE: .16 - something's wrong if they're charging more for M than
    L.  Check the prices at a reputable, professional, major-league
    plumbing supply shop, i.e., Spags, and I think you'll find type
    M is the cheapest.  And, if you look at them side-by-side, (end
    view), you'll see why.
    
    -db

    I apologize for everything. I have also re-checked the RELIABLE
    sources and found that BOTH were telling me one thing and meaning
    another. Seems they fall apart when hit with QUESTIONS from
    'beginner' plumbers like us.
    
    Yes, Type M, is the softest. Yet, they all say it makes NO REAL
    difference in a home application (Up to 100 psi or so.)
    
    That's the last time I will let the 'experts' tell me something
    and then swear to it!
    
    I crawl away... head hanging low...

    I want to move an exposed supply pipe into the wall. It is 3/4"
    threaded pipe so I think that means it is either bronze or steel. 
    The problem is that there is no accessible threaded coupling below
    where I need to go into the wall. Is there any way to make the
    transition from a plain, cut end of this type of pipe to regular
    copper? I could probably thread it, but the quarters are tight and
    I've never done this before. If this is what has to be done what
    would I need? Thanks.
    
       mitch

    
    
    	Most hardware stores will cut and thread pipe to your specs.
    
    	-Steve-
    

    re .1: The problem is that I can't detach the old section in order
    to bring it to the store to be threaded. I have a pipe with one
    end which I will cut off. The other end is inside a wall -
    inaccessible. 
    
      mitch

    re .3: There is no threaded part anywhere near where I have to cut
    it, so I couldn't use your saddle idea.
    
    The pipe comes up through the floor and is about 3-4" from the wall.
    Would I be able to cut threads on this?

Go to a plumbing supply store and explain your problem. They will 
sell you a brass adapter/coupling (solder-on, not threaded) which will 
take care of the problem for about a buck and a half,max.

I know, because I did it.
					Jack P

    re.6  Can brass be soldered to an iron pipe?
    
    Given that the pipe rises vertically (?) out of the floor, I would
    make the assumption that an elbow is located within 12" of the floor
    level.  Based on this assumption, I would chisel down to the elbox,
    soak it with Liquid Wrench rust remover for several hours, take
    a pipe wrench to the vertical pipe, remove the vertical pipe, and
    start piping fresh from the elbow.  Finish up the job by patching
    of the dig out hole with water-plug/hydra-crete type of cement.
    
    By-the-by, if this pipe is old and has been unused for a long time,
    pay close attention to the amount of internal corrosion built up
    within the pipe.  It is very NORMAL for galvanized pipe lines to
    clog up with corrosion so much that a complete replacement of the
    supply line from its connection to the supply main, well, etc.,
    is often warranted.
    
    Randy
    

    I expect to do some plumbing in the near future an I have a few 
questions about the solder that should be used in sweating joints.
I've read note 577, and it indicates that some of the people that use
this notes conference have been using the high percentage Tin solders.

	What type of solder is permissable under the most
	recent codes (90%, 95%, 100% Tin)? 

	Does a normal propane torch generate sufficient heat 
	to use the 90%+ Tin solders or do I need to use some 
	other fuel, like Mapp Gas, and if so, is a special 
	torch required (e.g., a Mapp Gas torch for Mapp Gas)? 

	Do I have to go to a plumbing supply store to get the
	right solder?  (Any suggestions for the Chelmsford, 
	Mass. area)

    So far the hardware stores I've looked in are still selling 40 Tin/
60 Pb or 50 Tin/50 Pb solder as plumbing solder.  When I asked about the
high percentage tin solders in one place, I was told that they didn't
carry it because a normal propane fueled torch wouldn't generate a high
enough temperature to use it. 

    Any clarification on the right solder, fuel, and torch to use
for sweat soldering plumbing joints would be appreciated.

	Thanks,
		Richard

	Warning!!!

	You neglect to say how old this pipe might be.  My house was 
	built in 1929 and I have a little of everything in it.  Galv.
	pipe, copper tubing, steel, lead drains and THREADED 3/4" COPPER
	supply lines (The majority is this).  Be warned that attempting to 
	do anything with this kind of line is not an hour project, it will
	snap at the THREADS of a fitting one or two levels down from
	where you are working, I know from experience.

	If this is your situation 1295.8 has one option run new pipe
	the other option is get a plumber.  I'm not afraid of doing
	plumbing but there are some situations that unless you are
	a complete masochist are worth hiring out.

	Good luck 

    I've used the 95/5 solder with a propane torch and had no trouble.
    You must use the 95/5 for water supply pipes.  The other solder
    can be used for heating pipes.  Spag's has the 95/5, most places
    should have it since it is now illegal (at least in Mass.) to use
    anything else.
    

    Anybody know why Mass now requires 95/5? I have never heard
    of any failures due to the use of 50/50.  Just guessing I
    would think:
    
    1 - Concern over toxic effects of lead
    
    2 - Concern that plumers might lose business, make it harder
    to do.
    
    3 - I don't know what I am talking about and there are 50/50
    failures
    
    
    - gerry

My understanding, Gerry, is that your guess #1 is correct, i.e. concern 
over lead poisoning.

I've never heard of reliability problems with 50/50, either.

    Somerville also carries it.  Just about everyone does.  Somerville
    had a little article from ???  pasted to the shelf that indicated
    that the reason for the code rules was as .-1 said - lead poisoning,
    not due to strength problems.
    

    Just saw 1 lb rolls at Spag's for 11.99.  They were out of the 1/2lb.
    rolls, though.
    
    There was a big (little, maybe) hoopla a little while back about lead
    accumulating in the water supply lines when the water stood still.
    Especially bad first thing in the morning when the water has stood in
    the 50/50 water lines all night.  They suggested running the water for
    a few minutes to flush the line.  This significantly reduced the
    lead content, they said.
    
    Phil

    
    	What I have seen around is 95% tin 5% antimony as the most common
    replacement for 50/50. If your looking for something a little stronger
    use 95% tin and 5% silver. It sounds expensive but I easily got
    10 3/4" connections out of one $3.98 oz.
    
    
    
    
    
    
    

    Update: I followed the advice in .6 and the fitting was just what
    I was looking for. Send mail in 20 years to find out how it held up.
    Thanks.
    
       mitch

I've ripped out all the plumbing and FHW piping in a bathroom.

Anything wrong with re-using the copper pipe (assuming cleaned-up joints):
    - for sink/toilet/tub?
    - for FHW baseboard?

(I live in NH, where I can do anything  ... well, sort of.)

    Depending on the age of the copper pipe.  The water in the southern
    N.H. area has a problem with acid concentration that tends to eat
    away at your pipes.  I'd check carefully for any corrosion that
    may be apparent before reusing any of this.  The risk is that you
    may complete installation only to find a leak in a week...
    
    jim
    

    The copper pipe used for FHW baseboard is the thin-wall stuff. 
    First, it doesn't have to withstand the pressure of domestic water
    lines, and second, you WANT it to give up the heat.   It's also
    3/4 inch.  Copper water lines tend to be 1/2 inch.   Given that
    it isn't corroded too badly, it can certainly be reused for plumbing
    water lines.

    Sorry folks..lost connection to JOET-
    
    I have the following problem and hope that there may be some
    information from my fellow noters.
    
    I have a new home (9 months) that is a split-level.
    
    I had the contractor install a 3/4 bath in the basement.  I would
    first like to state that there is no moisture in the basement.
    
    The problem we are having is with the in-layed floor.  About two
    months ago we noticed some stains appearing in the floor (light
    tan).  I notified the contractor and he gave us a few ideas to try
    to remove the stains.  These did not work.  He had a floor expert
    check it out, the expert states that the stains are CALCIUM coming
    from the concrete floor.
    
    Heres where were at-  The contractor and flooring person said that
    there is a SPECIAL in-layed floor that is Calcium proof, the contractor
    agrees to pay for the reomoval and reinstallation of the new floor
    and I am to pay the difference in price. ( I have no objection to
    this as it is fair, I guess.)
    
    My questions are-
    
    1. Has anyone ever heard of this type of thing happening?
    
    2. Has anyone ever heard of this type of "special flooring"?
    
    3. What is the general price difference in the two floors?
    
    4. How should I treat this with the contractor as the 1 year warranty
       on the house will run out in February 88. (What if this happens
       again in 7 months will the new floor be under warranty still?)
    
    Any and all comments will be greatly appreciated.
    
    Regards,
    
    Bob Montville
    262-8291
    JUNIOR::Montville

    Cut off the ends of the old pipes that already have solder on them.
    It adds enough thickness to make it very difficult to put new fittings
    on (even though it may look like a "feature" since the pipe is already
    tinned).
    
    Don't reuse old fittings.  New ones are cheap enough.
    

    But if you decide not to use it, I will be glad to take it off your
    hands for a VERY modest fee.
    
    
    

    No, there's no other way to fix it.
    
    Wrap a wet rag around the other joint ??

    Try:
    
    A heat sheild - a material that doesn't burn to deflect the heat
    (hopefully someplace not flammable).
    
    A heat sink (the wet rag idea) attached to the pipe not to be disturbed
    to absorb the heat.  Like a large clamp-on metal device.
    
    Leave water in the pipe not to be soldered if possible.  Check out
    you valve combinations.
    
    Solder both joints at the same time.  How good are you at soldering?
    That way they will both be ok when you are done.

    	A pair of vice grips and make sure they hang straight down.
    I had a pipe turn and come loose from the weight of the vice
    grips.
    

    Can anyone tell me how to remove crayon marks from wallpaper?

    We use WD40 spray. It works on many other surfaces as well.
    
    -Dick
    

    The best thing i have found is good old TOOTHPASTE.
    

    Wouldn't the OIL in WD40 leave an even  bigger mess (on wallpaper) to
    contend with than the crayon mark itself? 
    
    Charly

while we're on the subject... how do you get fingermarks (from
newspaper-stained hands) off of latex gloss paint without marring the
finish? 
			thanx/ (he-of-the-sweaty-fingers)

    I have used a large "Pinky" eraser to remove crayon off a
    semi-gloss painted wall. works fine.                
    

	
	Two products available at paint stores...

			'Goof-Off'
			'Oops'
	
	Both are designed to take dried latex paints off surfaces.
	The containers also state that other marks such as lipstick
	crayons, will come off too.

    
    I learned this from my grandmother and it works, but you have to
    be very careful!!  Take a good size piece of a brown paper bag,
    hold it on top of the crayon mark and iron it off.  Be sure the
    iron is on a dry setting (not steam) and don't hold it in place
    for too long.  Work slow and keep checking your progress.  Move
    the paper once you've got some crayon on it, otherwise you might
    iron back on some of the crayon you just ironed off.  I've done
    this on regular wallpaper in our old house but haven't had the
    "opportunity" to use it in this house which is papered with the
    pre-pasted type so I don't know if there would be any difference.
    
    Conni

    
    	RE.0 rubbing alcohol or ....have a drink like Gin or Vodka.
    
    any residual stains ...lemon juice.
    
                                ___GM___

	A friend has used lighter fluid to remove crayon from semi-gloss painted
walls.  Whatever you use, test a small inconspicuous area of wall first.

Good luck!

    I sweated some joints for a new bathtub/shower, turned on the water
    and had 2 leaks.  I pulled everything apart, re-cleaned it, sweated
    it and still had leaks.  Tonight I'm going to do it all again and
    REALLY clean everything but I'm curious, is there a limit to how
    many times you can resoldaer joints?  Is there a point at which
    you should just use all new fittings?  I reused some of the old
    pipe I pulled out and am wondering if this could be part of the
    problem.

    George

    Any deformity of the pipe, such as due to squeezing when cutting,
    will create a space that the solder will not fill.  If the pipe
    has been banged, crushed or isn't absolutely round, replace it.
    
    If using solder flux, remember to use a minimal amount of it.  I
    use just enough to put a film on the pipe as any extra bubbles up
    and pushes the solder back out.  Also, don't use rezin core solder
    as the rezin will do the same thing.  Stick with solid core.
    
    There is no limit on how many times you can reuse a pipe.  However,
    if it keeps leaking, there is a reason and probably cause not to
    reuse it again.
    
    The rules are simple:
    	1.  Be careful - don't bang or crush the ends
    	2.  Clean the pipe with 3-O steel wool or emery cloth
    	3.  Use just a film of solder paste (little white can)
    	4.  Use solid solder
    	5.  Avoid over-heating so as to oxidize pipe
    	6.  Run the solder around the joint
    	7.  Try to twist the pipe in the joint to aid in tinning all
    		the metal or pre-tin, if necessary.
    
    My father taught me well.  I've done hundreds of joints and can
    count the leaks on the fingers of one hand.
    

    
    <.19 I sweated some joints for a new bathtub/shower, turned on the water
    <.19 and had 2 leaks.  I pulled everything apart, re-cleaned it, sweated
    <.19 it and still had leaks.  
    
    Unless you *really* enjoy this.  Just fix the joints that leak.
    Leave the others alone if you can.

    RE: .20

>   If using solder flux, remember to use a minimal amount of it.

    I've always put enough flux to cover both the pipe and connector.
    Better too much than too little.  The flux is what draws the solder
    into the joint.
    
    Remember to heat the connector (elbow, tee) and not the pipe.
    
>        	7.  Try to twist the pipe in the joint to aid in tinning all
>    		the metal or pre-tin, if necessary.

    I don't understand this.


    I would say not to re-use old pipe and connectors if you don't
    absolutely have to.  It just isn't worth the aggravation.  As I
    think you are finding out.  I'm no plumber but have done a lot of
    soldering lately (don't tell anybody) and haven't experienced leaks
    due the amount of flux I use.
    
    Phil

    re: last few
    
    I don't agree with twisting the pipe.  Any movement as the solder
    is cooling will almost always cause a leak.  It either causes a
    'cold' solder joint or it fractures the metal at the joint.
    
    Agree with the rest except that I'd like to add:
    
    Don't keep your 'dirty hands off the pipe'  Keep your 'HANDS' off
    the pipe.
    
    As soon as possible, flux the cleaned area to prevent oxidation
    or contamination from the air.  NEVER NEVER NEVER touch the cleaned
    area with a finger.  There is enough body oils even on clean fingers
    to contaminate the joint so that solder does not flow over that
    area.

    .22
    	Flux doesn't 'draw' solder, the wetting action of the solder
    in the small space created by close tolerances does.  The flux cleans
    the surface.  A film of flux on both the pipe and and the fitting
    will do the cleaning.  Too much flux tends boil and bubble and this
    can push the solder out, instead of sucking it  in.
    
    .23
    	Sorry if there was the implication that the pipe was to be twisted
    as the solder cooled.  That would be dumb and would result in the
    cold solder joint as you suggest.  What I ment was that twisting
    the pipe or connector while heat is applied can help to cause the
    solder to flow around the pipe, it it didn't for some reason.  I
    also frequently withdraw the pipe or fitting to see if the tinning
    is complete (again with heat still applied).  My last step is always
    to go around the joint with a little more (not too much) solder
    and NEVER move anything as it cools.
    
    	The idea is to prevent any leaks from the beginning as fixing
    a leak after putting water in pipe can be a drag, especially when
    it's in a place that's hard to drain.  Like I said, I've had very
    few leaks in many hundreds of joints over 30 years of practice.
    

    RE: .24
    
    The flux melts almost immediately after putting the torch to the
    connector.  Any excess flux should come out at this point, but the
    connector will not be hot enough to melt the solder.  It usually
    takes a few more seconds.  I just don't see how the flux could still
    be boiling when the connector is hot enough to melt the solder.
    I would still advise, better too much flux than not enough.  And
    I'll second the "don't touch it" replies.
    
    Phil

    I used to reuse pipe and fittings; I quickly decided it just wasn't
    worth it, except in an emergency (the stores are all closed and
    you need one more elbow to finish the job).  Fittings are about
    a quarter apiece, or less, at Spag's, and 10' of 1/2" tubing is
    about $4.00 or something.  If it takes 10 minutes to clean up a
    used elbow, the rate of return on your labor is something under
    $2.00 an hour.  
    
    I've never heard of twisting the pipe as you're soldering it, and
    based on everything I've seen, read, and done, there is absolutely
    no need to if the joint is clean, fluxed, and heated properly.
    If the preparation is done correctly, making a good solder joint
    is almost automatic.
    If twisting helps you make good joints, by all means keep on doing
    it, but I've never found any reason to.
    
    I would agree with the "thin" coat of flux though; don't skimp on
    the flux, but there is no need to put on gobs of it, either.

A plummber once told me that when you're done applying the solder, but 
before it hardens, you should wipe around the joint with a rag.  He said 
that will insure a good-looking join that will not leak.  I've been 
doing it that way ever since, and although it may just be superstition, 
it works for me.
					>>>==>PStJTT

    
      twisting a pipe while soldering or immediately after, supposedly
    before it "sets", will cause voids between the walls of the fitting
    and the pipe.  You can be considered lucky that the joint hadn't
    set (only those that don't leak).  Remember, copper tubing radiates
    heat readily and cools rather quickly.  Besides the neatness of
    the joint, wiping it before it cools forms a fillet and increase
    the sealing surface.

    Our water precinct has just informed us that we need a back-flow gizmo
    installed "by a licensed plumber" (we're in New Hampshire).  Assuming I
    can get "permission" to do this myself and have some license-owner
    inspect it, I'd like a pointer or two.
    
    How do I dry the pipe just inside the main shutoff?  I've learned the
    hard way that even one molecule of water in a pipe will prevent solder
    from "taking".  I don't want to spend forever waiting for the pipe I
    cut to drain and dry.  Can anyone suggest a quickie way to prepare for
    this piece-of-work?
    
    Any other advice cheerfully accepted.

    Your torch will dry it in a jiffy.  That's not the whole problem, though.
    
    Water will continue to drip out of the nether regions of the plumbing
    system and spoil your work, especially if the shutoff values aren't
    working completely.  So get a small chunk of bread from the kitchen and
    stuff it into the pipe.  It'll plug things up for awhile, then it'll
    dissolve once you turn the water back on again.  Be sure to stuff it in
    far enough that your torch-work doesn't toast it (toast leaks).

>< Note 2990.0 by PAMOLA::RECKARD >
>   Can anyone suggest a quickie way to prepare for this piece-of-work?
    
	Use compression fittings.  The guy who invented them should receive
 the Nobel Prize.  By using them, you can literally connect pipes with the 
 water running.  I used them to tap into my main supply for a new �-bath and
 after years of trying to sweat wet pipes, they made a tough job a breeze.

	The short lengths of pipe that may need to be sweated to the back-flow
 valve can be done on the bench, nice and dry.  The actual connections to
 the main pipe can be done without having to worry about wet pipes.

							--Mike

Reply .2 seemed like a nifty way of doing it, so I sent mail to Mike for
clarification.  His reponse follows.

By the way, our water precinct guy (a little reluctantly) said "Sure, if you
know what you're doing, go ahead and let me know when you're done and I'll
take a look-see."  I think what persuaded him was my using this nice buzz-word
"compression fitting".

Anyway, clarification of this compression fitting follows ...

Thanks again for your help, Mike.

	A compression fitting (generally brass) utilizes a ferrule and screw
 system to essentially "squeeze" (compress) a soft material (the ferrule) onto
 a pipe in order to effect a seal.  It's a solderless connection, the same as
 is used in faucet hookups.  Crude drawing follows-- 


	   _____					 _____
	  |vvvv-|	    |VVV-| |-VVV|		 |vvvv|
	__|_________/-\_____\___ | | ___/_______/-\___________|_____
	  |	    | |	       | |_| |		| |	      |
   pipe	  |         | |	       | |_| |		| |	      |   pipe
	--|---------\_/-----/--- | | ---\-------\_/-----------|----
	  -vvvv-|	    |VVV-| |-VVV|		 -vvvv|
	  |-----|					 |----|

	   NUT	   FERRULE     COUPLING	      FERRULE     NUT


	So-- if your back-flow valve is just something that gets put in your
 main supply line (I think that's where it goes), all you do is solder 2 short
 lengths of pipe (6" maybe) onto the inlet and the exit sides of the valve
 (making an "assembly"), cut a section out of the supply pipe slightly longer
 the total length of the valve assembly and insert the assembly into the pipe
 using the compression fittings.  When I made my connections, the water was
 literally running out of the pipe....but not for long!  Just tighten up the
 nuts and it's "no leak city"!

	Happy plumbing.....

						--Mike

As a follow-up question (or topic deviation, if you wish) ...

Can I get 3/4" compression fittings?  The biggest I've seen so far is 5/8".
I'm assuming that stepping down to a 5/8" fitting (let alone 1/2") is probably
against code (again, I'm in NH), and it may even be silly.

(5/8"???  What's that for?)

    
    I've seen 3/4" compression fittings...
    
    
    
    					... for $5.99!!!
    
    These things are very costly.  I can't imagine what the large ones
    cost.
    

>< Note 2990.4 by PAMOLA::RECKARD "Jon Reckard, 381-0878, ZKO3-2/T63" >
>Can I get 3/4" compression fittings?  The biggest I've seen so far is 5/8".

	Jon,  I'm pretty sure I've seen them at my local plumbing and heating
 supplier (Wheelen's P&H, Gardner MA).  If you like, I'll stop there and find
 out for sure (drop me a note if you do).  As far as cost goes, -1 is probably
 correct at $5-$6 apiece.  But to me, the frustration of trying to sweat drip-
 ping pipes is much more costly.

							--Mike

    You can get compression fittings up to several inches in diameter.
    Although up to 1" you get a brass compression ring and the larger
    sizes use a rubber compression ring.
    
    The larger sizes 3/4" and up are usually hard to come by, but they
    do exist.
    
    United (in Nashua) carries some of the larger sizes.  (I just had
    to get a 3/4" valve with compression fittings [a.k.a. bi-com valve]
    to put in the supply line for my house; the original was getting
    flakey and it was getting difficult to shut off the water in the
    house.)
    
    - Mark

Oh, yeah, I found some.  I called or visited 5 plumbing supply places - Goulet
and one other in Concord, NH; Colonial in Manchester; United Supply and one
other in Nashua.  Also Hammar Hardware, Nashua, industrial section.  Only
United Supply in Nashua ($5.23) and Hammar ($9.something!!) had them.

I bought 'em and installed 'em, and, so far, so good.

As a tangent, I've got a question on joining different types of copper pipe.
I bought some type L 3/4" (7/8" O.D.?) and sweated my check valve between two
short sections, which I then compression-fitted in place.  I used, for the
first time, a pipe cutter (nice!) instead of a hack saw on my short sections.
Then, when I first tried to cut the unknown-type in my cellar, the pipe bent
as I screwed on the cutter.  I was able to cut the stuff s_l_o_w_l_y, and the
compression fitting seems to be doing OK.  But, does anyone see any problem
with mixing pipe types?

>< Note 2990.8 by PAMOLA::RECKARD "Jon Reckard, 381-0878, ZKO3-2/T63" >

>I bought 'em and installed 'em, and, so far, so good.

	Good!  Glad to hear it worked for ya.

	The difference between type L and M is the wall thickness, L being the
 thicker of the two.  As far as mixing the two types, I guess there wopuld be
 no problem, but I always use L just to be safe anyway.

	From your description, it sounds like maybe you were
 not using the tubing cutter in the proper way as I can't picture ever 
 "bending" a type L pipe with a cutter.  The idea of the cutter is to only
 cut a little at a time.  When you first put the tool on the pipe, it should
 be screwed on until the cutting wheel just touches the pipe.  Then another
 � turn of the screw will make the wheel "bite" into the pipe a small amount.
 Then you make one revolution of the tool around the pipe, "scoring" the pipe.
 After each revolution you tighten the screw a little more and make another
 revolution until the pipe is cut through.

	It sounds like you tried to cut all the way through the pipe wall at
 once.  Is that what you did?  That's the only scenerio I can picture that 
 would cause a pipe to "bend".

							--Mike

Just to clarify, I bent the old, narrower-walled pipe.  Again, using the cutter
on my new type-L (thick-walls) was my first experience with the tool.  I found
I had to screw it on pretty hard - otherwise it would "wander" and cut on a
different line with each turn of the tool.  When I got to the thinner-walled
pipe, I applied (I think) the same pressure to start, and it bent, or dimpled
the pipe right under the cutting wheel.  Starting over again in a different
place, cutting very gradually, I was able to cut it successfully.

As well as being maybe a type-M (or whatever), the pipe was very old (couldn't
see any Type markings on it) and maybe eroded? even thinner?  I dunno.  I just
hope it's not a "new wine in an old wineskin" situation.

>< Note 2990.10 by MCNALY::RECKARD "Jon Reckard, 381-0878, ZKO3-2/T63" >
>                                -< thick/thin >-

	Ahh, now I see.  Yes, I'd say it was probable that age/corrosion + a
 thinner wall could cause a pipe to buckle under the pressure of a cutting 
 tool.  As long as the fittings are working ok, you're probably all set.  They
 exert a uniform force around the whole circumference of the pipe and aren't
 likely to collapse it.

							--Mike

    What "tricks" are there to drying out residual water inside a pipe
    to that I can be sure to get the fitting hot enough to resweat a
    joint.  I have unsuccessfully tried to heat up this fitting to no
    avail.......the solder simply won't melt.
    
    I've used the "rolled up bread ball" trick if I have an open end,
    however, this is on a "closed" end pipe.
    
    Thanks, 
    
    Jonathan

    RE:4 
    
            Your answer is in you note title.
            Get "hotter" heat source.

I asked the same question in some other note herein.  Someone recommended
compression fittings.  No sweat!  (Pun intended.)

It's easiest for me to say look for my note.  Or ask for them at your hardware
store/plumbing supply place and maybe a nice person will explain it.  I *did*
have a hard time finding the 3/4" fitting I needed - few places have that size.

    After reading all these encouraging remarks about compression fittings
    I decided to give them a try.  I found an interesting arrangement at
    Grossman's - a compression fitting built into a shutoff valve.  I am
    planning to use it on the intake line of a toilet.  Looks like it will
    save a lot of time considering the alternative.

Re: .12

I've got compression fittings on a set of sink shutoff valves.  I
prefer soldered fittings, but they do work if you tighten them enough.

Then again, I've never had trouble with water while soldering.

			Steve

    I never had trouble with water in the shutoff vales either - have you
    tried opening a faucet lower in the house after shutting off the main
    water valve to lower the level?  If you do that and then wait a little
    while (hard if you have a big family!) before doing the work, you ought
    to be OK.
    
    When we replaced the shutoff valves in the bathroom, we replaced them
    with screw fittings and valves that screw in - shutoff valves are
    pretty junky devices, and will leak (even if you repack them - we tried
    that too) after they have been turned enough times.  This way, next
    time they need to be replaced, the job will be real easy - no
    soldering!
    
    Next plumbing job is to replace the shutoff valves for the outdoor
    faucets - not looking forward to that one as one of the valves is not
    in a very accessible place - I am hoping we can get away with just
    repacking them as they are full-sized valves!
    
    /Charlotte

Re: .14

Just don't do one thing I did.  I was working on a hot-water line in the
basement and had opened the hot-water control of an upstairs sink to allow
the water to drain down.  My son asked if he could use the sink, and I told
him it was ok to use the cold water.  He turned it on and water gushed out
my open pipe in the basement.  The water went up through the faucet and
back down through the still-open hot valve into my pipes!

			Steve

<    What I have seen around is 95% tin 5% antimony as the most common
<    replacement for 50/50. If your looking for something a little stronger
<    use 95% tin and 5% silver. It sounds expensive but I easily got
<    10 3/4" connections out of one $3.98 oz.
    
I just bought some solder which is 95.5% tin, 4% copper and 0.5% silver. It says
that it will remain bright and shiney. Are there any problems using this stuff, 
and will it work with standard paste fluxes on copper pipe?

Dave

P.S.	While on the subject of soldering copper, I have a craft project which I
	will build out of copper pipe fittings. When it's done, I want to polish
	the copper and do something to treat it to get a bright blue-green 
	patina, like weathered copper on a cupola or weather vane. Anyone know 
	how to accomplish this?

    Re: .7
    I think that's the alloy I got when I got some lead-free solder;
    it handles just like regular solder.  No problems.  If you can
    use tin/lead solder, you shouldn't have any trouble.
    
    Someplace I have a book of formulas that tells how to get various
    patinas on copper, but I have no idea where it is...I might suggest
    salt and water as something to try, but that's just a WAG.
    

See note 4270.11 for a source for various patinas, including copper.

Cold water pipe of my shower.....why did it leak?

The horizontal section of �" copper pipe leading to the shower developed a
series of pin-hole leaks running along 18 inches, at about the 9:00 position.
The inside had a build up of green stuff along the leak path, and the wall was
pitted.  The vertical section looks real good.  The house was re-plumbed in
1943, and I (with fingers crossed) have not seen leaks anywhere else.  We live
in Framingham, MA and have MDC water.    Is it time to move?

   |    |                      Cross section of �" copper pipe: 
   |    |   |<-18"-->|                        .__.
   |    `------------                        /    \
   |                                        |      |
   |        �  �    �   <-leaks         .--> \o   /
    `------------------                /      `__'
                                      /
                          leak here, with row of green stuff along the inside.
    

This happened in the house I grew up in, too.  What might have happened is a
piece of thinwall (type M) pipe used where it shouldn't be, combined with
acid water that slowly eats copper (do you have green stains in your sink?)
Or just a piece of defective pipe.

-Mike

    	I've been told that the lesser expensive variety of copper pipe
    will last roughly 20 years with acidic water. My house is 20 years
    hold. I've lived there for 2.5 years, and I've fixed about a dozen
    pinhole leaks so far, one of which was inside a wall. Every plumber
    that's been to the house has told me I need a whole new set of copper
    pipes (and lot a little piece at a time the way I've been doing it).
    Many of the houses in my neighborhood are the same age and have
    recently had this done. Some of the pipe I've removed is paper thin.
    Kind of scarey knowing that's what the pipe in the walls looks like,
    but unfortunately, I don't have the $2000 to replace all the pipe at
    once (the rough estimate provided by several plumbers), and I'm not
    going to attempt it myself. My solution, so far, is when a plumber
    comes out to the house to fix a pinhole, I try to convince him to
    replace as much pipe as I can. Slowly but surely, I'm making a dent!
    However, I wouldn't say this was the most economical solution in the
    long run!

This will doubtless turn out the wrong place to ask this, so,
moderator, move it if you have to.

A couple of weeks ago, I noticed that someone had turned up
my (gas) water heater's heat control to maximum. Just who did
this, when and why, are intriguing questions not really
relevant to the matter at hand. As soon as I noticed this, I turned
it down a notch (wasn't sure what it had previously been set to,
though I know it wasn't at max).

Then a couple of days ago, I noticed a little puddle on the basement
floor close by. The source of the water, I finally found, was a 
pinhole leak in the (copper) outlet pipe from the heater, that resulted
in a tiny spray of water. To deal with that until I could get a 
plumber in, I just closed the faucet on the heater inlet, simply
to relieve the pressure in the faulty pipe. Coincidentally, I also 
turned down the heat control a couple more notches.

Now, here's the weird part: Later I opened the inlet again and the
leak was gone! Could this be because with the cooler water, the
copper pipe contracted enough to close up the hole? It seems 
bizarre but I see no other explanation. And if so, does that mean
there's no real urgency to getting it fixed, or is it likely to
recur even at the lower water temperature?
Any comments appreciated.

...Robert

    If you had a hole before, you've still got one obviously.
    
    BTW - That's a pretty simple fix for the DIY'er...
    
    Edd

    Not sure why it stopped...maybe less pressure due to lower temperature?
    
    In any case, as .1 says, it's still there.  You have been warned.
    If you ignore the warning, the Plumbing Gods will make it let go
    with a great SPLURSH! at 2am on Christmas morning when you have
    a house full of company, no open stores, and all the plumbers are
    at the annual plumber's convention in Bermuda.

>    If you ignore the warning, the Plumbing Gods will make it let go
>    with a great SPLURSH! at 2am on Christmas morning when you have
>    a house full of company, no open stores, and all the plumbers are
>    at the annual plumber's convention in Bermuda.

    Well that's really what I wanted to know;  obviously the hole's
    still there. So what's the easy fix?

    Cut and replace?
    
    Dave'
    

    
    The easy fix:
    
    (ignore all of this if you live in a state like MA like I do, because
     it's illegal to do your own plumbing and if the copper cops are
    watching they'll put you away FOREVER.)
    
    Go to the store and get a couple junction fittings the same size
    as your leaky pipe.
    
    Shut supply line to tank off. Open all the hot water faucets in the
    house. Hopefully you have a drain valve somewhere near/after the hot water
    outlet on the tank. If so, open it and drain the hot water pipes. (To 
    drain you have to remove the little screw cap on the side of the valve.)
    
    Once you've got as much water drained as possible, cut the pipe with 
    a tubing cutter right where the pin hole is. Look how wrong you were
    thinking the pipe was empty. 
    
    Make sure there is no water left in the heater side of the cut pipe.
    Draining a little water off from the tank should do it.
    
    Inspect the pipe. You may have lots of little pin hole fetuses waiting
    to be born. Make sure the pipe appears solid.
    
    Now use one of your fittings to join the two ends of pipe back
    together. Solder them. Turn the water on.
    
    Edd

It may be a good idea to replace the whole stretch.  Desolder at both ends
and solder in a whole new piece.  My father had a whole stretch break out
with a zillion pinholes pretty much all at once.

Also it is VERY VERY VERY important to get the copper clean else the solder
won't stick and the joint will leak.

-Mike

    
    >> Once you've got as much water drained as possible, cut the pipe with 
    >> a tubing cutter right where the pin hole is. Look how wrong you were
    >> thinking the pipe was empty. 
    
    You've done this before, haven't you?  ;-)
    
    I'll second .6 (and .7, if inspection gave any hint of further
    latent pinholing in the tubing).  It's just about what I'd do.
    
    Soldering copper tubing is easy IF you have the technique down.
    As .7 says, the key is CLEAN, CLEAN, CLEAN.  Polish the ends of
    the tubing and the inside of the connector(s) so you have bright,
    shiny copper with no trace of corrosion.  Steel wool works pretty
    well, or fine sandpaper or emery paper or a wire brush.  Immediately
    after polishing, apply a thin layer of flux to the surfaces.  (I
    use the "Nokorrode" paste flux that comes in a little white can.)
    Assemble the parts, then heat with a propane torch.  Heat the biggest
    mass (i.e. the fitting, not the tubing) and apply the solder to the
    joint on the side opposite the heat; the solder will run toward the
    heat.  When the solder flows into the joint, don't overdo it.  Solder
    that runs down the outside of the tubing doesn't help, although
    a lot of plumbers seem to think so.
    NOTE: you need to use lead-free solder for water supply systems.
    It works just about the same as the old lead-tin solder.  

      I  had  a similar problem with the hot water line to the shower in
      one of our bathrooms. Brand new pipe, too! It only leaked when the
      shower was used. Obvious problem, right? People were splashing too
      much water on the floor, right? 
      
      Well,  after I yelled at everyone to stop splashing, my wife dried
      the floor, turned on the shower and made the leak  appear  with  a
      totally dry bathroom floor.  So I crawled off into the crawl space
      and found  the  leak.   Fixed  it  essentially  as  .6  (I  think)
      suggested.
      
      Conclusion:   It is possible for a pipe to have a hole that is too
      small to leak (at least not noticeably) when the pipe is cold, but
      when the pipe warms up it expands and the hole gets bigger and...

      I  also  agree  with .7 (I think).  If the length of pipe with the
      leak is at all suspect, replace the  entire  piece.   It  is  very
      little  extra  work  and cost once your at it anyway -- a LOT less
      that having to re-do the entire job when the next leak starts.

    There's no water in the pipe to the shower head if the diverter on
    the faucet isn't activated...
    
    Edd

      A  clarification on .9 -- the leak I had was in the hot water pipe
      that lead to the valve for the tub/shower, not the pipe  from  the
      valve to the shower head.
      
      Sorry it this confused anyone.

re: 4655.6                 Tiny leak in copper pipe                     6 of 11
>--------------------------------------------------------------------------------
>(ignore all of this if you live in a state like MA like I do, because
>it's illegal to do your own plumbing and if the copper cops are

I think it depends on WHERE in Mass one lives. I live in Mass, and 
I pulled a remodeling permit from City Hall to install my own bathroom 
which includes plumbing and electricity, as well as the rest of the stuff.

When physical problems interfered with doing my own work, I was informed
I could get anyone I wanted to do the work. The catch, is that it must
pass the inspection. And this is valid (in this town) only for Remodeling
work. It is not applicable to New Construction. 

An awful lot depends on the town, and how the 'rules' are interpreted.

In general, most homeowners are free to do their own repairs.
One caveat which shouild be made, is that all work done should be done to
code, even if it won't be inspected. Because no matter who does the work,
the workman owns the liability for the work done. (should that be 
work-person ?)

-Bob

Its just my opinion, but I think the 'public' reason for permits is to ensure
that public safety is maintained, even among fools. But the real reason is to
identify those properties which should be subject to a higher tax !  :^)

    Note 388 is dedicated to plumbing permits in Mass.
    
    George

    No, No, No - the EASY fix is a two inch square cut from an old inner
    tube, and a pipe clamp - the screw down kind. Wrap rubber around pipe,
    put clamp around, and tighten. Will probbably stay fixed for years. 
    But, cutting and sweating is more permanent.

    I cannot totallyu recall, but from my days of physics I clearly
    remember the 'hole in metal - expansion' delema.  And if I remember
    correcly the hole will stay the same size no matter what the temp. 
    because the hole expands opposite (think about it).
    
    
    now don't hammer me.... guess i could look it up... %$#@! now where did
    i put that darned book.

    re: .15
    Like a lot of things in physics classes, there were almost certainly
    a lot of "simplifying assumptions" involved.  We're talking about a
    hole in a round tube.  While *in theory* the hole may stay the same
    size, in actual practice there may be flex of the tube caused by
    heating, unequal forces caused by the curvature of the tube that pull
    the hole open, and on and on.  
    

    The thing that does vary dramatically with temperature for water is
    viscosity, and thus also its surface tension. If one has a very small
    hole, then surface tension may be sufficient to stop it from leaking
    against even quite high pressures - raise the temp, lower the viscosity
    and, bingo, it leaks.
    
    Injectors in diesel engines have very fine holes - the injector
    pressure runs two to three thousand psi. The first five hundred or so
    psi is to overcome the viscosity problem and actually get fluid through
    the hole. The remainder is to overcome cylinder pressure and to get the
    fluid moving fast enough to atomise properly (and to get enough into
    the cylinder).
    
    The effect is very easy to visualise with very high viscosity fluids
    like waxes.
    
    regards,
    Michael Watts.

    re: .17
    The viscosity of water varies dramatically with temperature???
    
    Seems to me that water at 32+ degrees flows just about the same
    as water at 100 degrees or water at 180 degrees.
    
    (Unlike oil, for which the viscosity generally does vary dramatically
    with temperature, from barely flowing to free running.)

    Depends on what you call dramatic, I suppose - oil does show
    exceptional variation. Water at 4 Celcius is about 1
    centistoke, and is about .55 centistokes at  100 Celcius. If memory
    serves me correctly this is a difference in surface tension of about
    40Kpa - I don't recall my imperial units so well these days, but I
    think this corresponds to approximately 12-15psi.
    
    Even gases show variations in viscosity - about 5% per 100 Celcius
    degrees is the rule of thumb I recall for approximately atmospheric
    gases.
    
    Also, now that I come to think about it, I'm not sure of the assertion
    that holes stay the same size with variations in temperature. If one
    considers a plate with a hole, and then heats the plate,
    one applies a scalar transformation field to the plate to get the
    relative positions of new and old points in the plate. This would
    indicate that the hole does expand.
    
    Old plate (x,y) moves to heated plate (x+cx,y+cy), where c = f(T) and
    presuming an isotropic plate.
    
    If the plate has a hole diameter d, then wlog diametrically opposite 
    points are (x,y), (x+d,y), and the heated plate points are (x+cx,y+cy)
    and ((x+d)+c(x+d),y+cy). Subtracting the points for the cold plate
    gives the diameter of the hole as d,  and for the hot plate as d+cd. 
    
    In straight practical terms, why otherwise would heating/cooling two
    objects allow shrink fitting?
                                 

re: .15 and .16 (I think)
      
      I  theory  and  in practice a hole in a pipe or sheet of metal (or
      most anything, for that matter)  gets  larger  as  the  pipe/sheet
      expands  uniformly.   Expansion  form  heating is uniform, for all
      practical purposes.
      
      Think  about  the metal (or ?) that forms the circumference of the
      hole.  That metal is expanding, right?  So, it  follows  that  the
      circumference  of  the  hole  is increasing.  If the circumference
      increases and the hole stays round it must get  bigger.   It  does
      stay  round  (in  the absense of come other force) and it does get
      bigger.
      
      It is possible and I have personally observed holes in both copper
      and PVC pipe (or maybe it is CPVC, but that is beside  the  point)
      that  do  NOT  leak  when  the pipe is cold but DO leak when it is
      warm.  This is the result of the hole getting larger as  the  pipe
      heats and exands.  

Charlie,

You may be looking at this wrong.  I get boogled when I think about it.
Remember, it is the metal that is expanding, not the hole.  For example:


	 _______________________
	|			|
	|	    ^		|
	|	    |		|	OK, so all the metal is expanding
	|	    V		|	evenly.  Is the hole expanding?
	|   <-->    O	<-->	|	Or is the hole being compressed
	|	    ^		|	by the expanding metal around it?
	|	    |		|
	|	    V		|	Beats me.  I am not a Mech E.
	|_______________________|

Stan

    Stan, if the metal is expanding around the hole, how could it possibly
    be compressing it?

    ...because the metal should (in my non-ME mind) NOT be expanding away
    from any particular point, but rather, expanding in ALL directions.
    
    Can't argue with the "I saw it happen" note though...
    
    Edd

    Don't forget that this is a 3-dimensional object.
    
    The pipe's diameter is expanding too, and (I can't think the right
    words for the concept) is moving "outwards" from it's original
    position.  The diameter expansion may, percentage wise, overwhelm
    any inwards effects on the hole.
    
    	Dave.

    This may be an off the wall example, but think of a balloon with
    printing on it.  As the balloon expands, so does the printing.  Now
    think of the printing as a hole.  Granted, the expansion in a copper
    pipe is going to be MUCH less (god, I hope so! :-) ) but I would think
    the principal is similar.

    -Bob 

re: .25

Bad analogy.  The printing is on the surface of the rubber of the balloon. 
Thus, it acts the same as a piece of rubber.  The air in the hole in a metal 
plate can transmit no force.  Plus, a rubber balloon is expanded by the 
pressure within it.  Thus it is being *stretched* at all points.  This is 
easily proven by sticking a balloon with a pin to generate a small hole and 
noting the result.  The hole gets bigger rapidly.  However, if a metal plate
is heated the metal expands in all directions.  Therefore, at all points in
the plate the forces are in balance.  It is not being stretched by an inner 
pressure like the balloon.  I can't say if the hole gets larger or smaller.

re: .24

Eeeeps!  3D!  I can't even think about the 2D case without my eyes crossing.

Will some ME put the full blown derivation with all the partial derivatives 
in here just for yucks and settle all this?  I remember doing some flat plate
theory but that was ages ago.

I am outta this discussion.

Stan

    re: last several
    
    It's apparent to me that most of you spent too much time in your
    friend's dorm room staring at black light posters, listening to Jimi
    Hendrix's Electric Ladyland, and Clintoning(tm) illegal herbs instead
    of being in the classroom...  [many :-)'s]
    
    John
    

    RE: .27
    
    Now, those were the days!
    
    Marc H.

    re: .27
    
    You say that like it's a problem...
    
    ;^)
    
    Edd

    > You say that like it's a problem...
    
    No, actually, I was wondering if it was any of these noters that came
    over to my dorm room...  :-)
    
    John
    

      Folks,  this  is  NOT  rocket  science,  even  if  it  is commonly
      misunderstood. It is simple, high school physics. Let me state the
      reality  one  more  time.  Then we can all get back to our various
      substance abuses.  ;-)

      With  a very few exceptions, mater expands when heated.  (Ice near
      freezing is an exception.)

      If an items made of an homogeneous material is heated uniformly it
      expands uniformly.  If it has a hole in it, the hole expands.

      If the items is non-homgeneous different parts of it may expand at
      different  rates.   This  may  cause  distortion  which   is   not
      predictable without more information about the makeup of the item.

    So how come the material around the hole doesn't expand *toward*
    the hole?
    
    Edd

>      Folks,  this  is  NOT  rocket  science,  even  if  it  is commonly
>      misunderstood. It is simple, high school physics. Let me state the
>      reality  one  more  time.  Then we can all get back to our various
>      substance abuses.  ;-)

Actually, materials problems similar to this are a great concern when building
rockets!  :-)

>      With  a very few exceptions, mater expands when heated.  (Ice near
>      freezing is an exception.)

Agreed.

>      If an items made of an homogeneous material is heated uniformly it
>      expands uniformly.  If it has a hole in it, the hole expands.

The definition of homogeneous material is one made of all the same sh...stuff
(loosely paraphrased  :-).  A hole is a serious non-homogeneity (also called a
discontinuity).  Prove it!  :-)

>      If the items is non-homgeneous different parts of it may expand at
>      different  rates.   This  may  cause  distortion  which   is   not
>      predictable without more information about the makeup of the item.

Actually, the distortion is caused by the hole in the plate and it can be
calculated.  I just don't know how.

Damn!  And I said I was going to stay out of this note.  I lied.

Stan

Re: .32
 
    >So how come the material around the hole doesn't expand *toward*
    >the hole?
    
    Look at it this way:

    The material around the hole *does* expand toward the hole, but it is
    connected to material that expands *away* from the hole at a greater
    rate.  Therefore, the net effect is that the hole expands when heated.

    Greg B.

    No No NO!
    
    You guys _have_ to apply the law of Circumstances.
    
    A.  The hole will remain closed when it's a normal workday between 9-5
    B.  The hole will leak in the early morning hours when no one is there
        to notice it
    C.  The hole will leak the most when it's the weekend or you're out of
        town. 
    D.  The hole will flood your basement on Christmas or NewYears Eve.
    
    Simple wasn't it  :-)  :-)
    
    Steve
    

    A good re-read of the second half of .19 could be what is required -
    its a very straightforward proof that the hole does expand along with
    the plate, for an isotropic (uniform) plate.
    
    Note that a pipe with a hole can be considered to be cube with three
    "holes" - an inside hole and an outside hole form the pipe, and a
    radial "hole" forms the actual hole in the pipe. Treated in radial
    co-ordinates the proof is too messy to type in, but is still very
    straightforward and the hole STILL expands.
    
    The printing on the balloon analogy is a good one - consider a plate
    with a hole and a disk of the same material as the plate which
    precisely fits the hole - now heat the plate with the disk inserted. Of
    course the disk will not be compressed, nor will a gap be created.
    
    regards,
    Michael Watts.

    Imagine a metal plate 3 units on a side, with a square hole one unit on
    a side in the center. Awful graphics below:
    
    
              ______________________________
              |        .         .         |
              |        .         .         |
              |    1   .    2    .    3    |
              |        .         .         |
              |........._________..........|
              |        |         |         |
              |        |         |         |
              |    4   |  hole   |    5    |
              |        |         |         |
              |........|_________|.........|
              |        .         .         |
              |        .         .         |
              |    6   .     7   .    8    |
              |        .         .         |
              |____________________________|
    
    Now heat it up so that all the 8 metal squares making up the plate
    become 1+x units on a side. Observe that the hole becomes 1+x units on
    a side.
    
    QED
    
    (Note that this is the same arguement that was made much earlier, that
    the circumference expands.)
    
    (Note that the arguement about "the sides of the hole expanding inward"
    is incorrect. The position of the sides of the hole is set by the
    rectangles labelled 2 and 7, and they expand outward.)
    

	    Didja ever notice how physics experiments never seemed to
	work out like they were supposed to?  You know, you get all 
	these wonderful calculations explaining how this force will
	interact with that and the result will be x... with an error
	of �25% (if you're lucky).  
	    Okay, most experiments didn't work out that poorly, but
	some of them were totally unpredictable.  What's this got to
	do with a pin hole in a piece of pipe?  Nothing, really.  But
	if the pipe leaks when it heats up, I'd replace it.  8^)

					Tim

>	if the pipe leaks when it heats up, I'd replace it.  8^)

      Alternatively  you could prevent the pipe from heating up by using
      it only for cold water or by providing refrigeration to  keep  the
      pipe cool when used for hot water.
      
      :-)  (wish I could draw a really BIG smiley face!)
      
      BTW  --  I think there were several places, including at least one
      diagram, in which it is asserted that every point expands in every
      direction.  That is wrong. Every point moves in only ONE direction
      during expansion.  That direction is directly away from the center
      of  expansion,  which is generally about the same as the center of
      mass, if you assume an object that is of  a  more-or-less  regular
      shape and a homogeneous material.

      As to the request to "prove it", sorry, that can't be done. All we
      have to go on is an enormous body of empirical evidence  that  has
      never  been  contradicted.   That is NOT "proof" in the scientific
      sense, but it is an accepted fact and we can be certain "beyond  a
      reasonable doubt" that the hole does expand when the pipe or plate
      expands.  It is a basic fact of the physical reality in  which  we
      (I, anyway!) exist.  If it ever changes, that will be B_I_G news!

    I should have read this note BEFORE I started soldering last night!! I
    soldered a joint next to another previously soldered joint and the
    older joint came apart due to the heat...next time I'll try the wet
    rag/vice grips method to transfer the heat..however, I have a
    question..
    
    When I re-solder the existing joint, will the solder take OK over the
    solder all ready coating the joint (using flux)..or do I have to get
    all of the old solder out and get back to copper ??
    
    Thanks

You'd be best off to take the old joint apart, clean and flux it and
re-solder.  You can try just heating it again and adding solder, but since
you can't get flux into the joint, you might not get a good joint.

					Steve

    
    How old is the old joint?  Resoldering an older lead solder joint is
    quite possible, but I've had less success with the newer low lead
    stuff.
    
    heatsink your "new" joint first. Get a thich wad of clean cotton cloth
    ready (or a manufactured desoldering wipe) and then heat the old joint
    until the solder flows.  Wipe off the solder from the pipe and the
    connector.  This should leave the joint just "tinned" and you should be
    able to dry fit it.
    
    Apply the appropriate paste flux to both sides of the connection
    and reassemble.  Reheat and resolder.
    
    Colin
    
    
     

>    soldered a joint next to another previously soldered joint and the
>    older joint came apart due to the heat...next time I'll try the wet

This may also be an indication that your torch is not hot enough or not set 
properly. It can be tricky to get the heat just right, but _ideally_ you 
should be able to get in and adequately heat the joint (and then get 
out!) quick enough so that de-soldering neighboring joints is not a 
problem.

JB

    If insufficient heat is the problem there are tourch kits available
    that take 2 tanks 1 propane and the other is oxygen. Just dial up
    the oxygen to get it as hot as you want. This also provides a much
    tighter flame.
    
    Brian V
    

Hello,

I need some advice. I am putting a tap in my water main for a sprinkler system. 
I ran out of "plumbing solder" and finished the job using "electrical" solder.
I mentioned this to someone here at work and he shock his head saying "ya better
rip that pipe out and replace the questionable solder with plumbing solder!". 

Just as I started to cry he said that "well maybe its the other way around?"

Whats the story? Do I need to rework these joints? I want to do it right but 
I don't want to do more work than is required.

Please advise!

thanks,
d.t.

"Electrical" solder has lead in it (60%, I believe).  When used in copper
water pipes, the lead leaches out over time and gets in your drinking water.
For this reason, lead solder has been outlawed for plumbing use in many
states and cities.

Also, the rosin flux in electrical solder can contaminate the water supply
(in addition to not working all that well on copper pipe).

				Steve

It's the other way around.  ACID CORE SOLDER EATS AWAY ELECTRICAL 
COMPONENTS.

FWIW, I've got an entire air supply system in my garage and basement (about 
200 feet) of copper pipe that's been soldered wit electrical solder.

When I bought my house in '78 I replaced a number of copper pipes and used 
electrical solder I'd bought at one of the monthly scrap sales in Westfield 
back in the mid seventies.  The pipes don't leak yet.

    Skip's right..."electrical solder" is just fine for copper pipe.
    The only thing you need to worry about is the flux; don't use
    acid flux on copper.  Rosin flux is fine, and it won't hurt you.
    The only possible concern is the lead in the solder.  If you let
    the water run for a while before you use it, you probably don't
    have to worry about that, either, although technically it's against
    code now to use lead-bearing solder on your water supply pipes.
    

    By the way...you've got your proportions backward on the tin/lead.
    Typically, solder for electrical work is 60% tin, 40% lead...unless
    somebody's a fanatic and has the precise eutectic alloy of 63/37.
    Anyway, it'll work.
    

Which is the bigger risk to health?
      The potential of lead leached from sweated copper plumbing joints
   or the potential of mercury leached from dental fillings?

Next question -
      Isn't it far more likely that I'll die of old age before I could
     possibly care about either of them?
 

>>Which is the bigger risk to health?
>>      The potential of lead leached from sweated copper plumbing joints
>>   or the potential of mercury leached from dental fillings?

Oh my god - I have to call my dentist and get everything drilled out and
replaced with plastic now !

From what I heard years ago there was some study done (always a study done!)
that "proved" that it "could" happen.  I think the study was done right around
the time that all the lead paint was being removed from houses - but it was the
leached lead from the small amound of solder in the copper joints that was
causing "higher than normal" levels of lead in the house dwelers.

Anyway, you can still buy and use lead based solder for plumbing - but it has
to on the non-potable systems in the house (FHW systems are the most common 
use).

>>Next question -
>>      Isn't it far more likely that I'll die of old age before I could
>>     possibly care about either of them?

Yup - unless of course you want to sit down and drink water from an "old house"
that has lead-based solder joints - and while you are drinking that water (has
to be hot water to increase the leach effect) you can stick a sharp object in
your mouth and scrap away at any fillings you may have.  Do that for the next
several years then maybe you'll care about it :-)

bjm

> Next question -
>       Isn't it far more likely that I'll die of old age before I could
>      possibly care about either of them?

	Smokers used to (and some still do) say that about smoking ....

��         <<< Note 5623.6 by MOLAR::DELBALSO "I (spade) my (dogface)" >>>

��Which is the bigger risk to health?
��      The potential of lead leached from sweated copper plumbing joints
��   or the potential of mercury leached from dental fillings?

    ...or, you want to sell your house, the buyer does a water
    test, finds lead, and knocks 25% off the price.  You die
    of a heart attack.

    Not that I think one lead soldered joint makes any difference
    at all...

There are still plenty of lead supply pipes in older houses.  But there's
typically so much scale inside the pipes that leaching is unlikely.

Boston, NYC, Philly, Chicago... all have solid lead pipes providing water
to millions of people daily. They've been there for a hundred years in
some cases.

Use your worry energy for the traffic.

    It was around 1980 when the transition from lead solder took hold in
    this part of the country at least.  I remember because I used to sell
    the stuff.  And the transition was slow because the newer "silver"
    solder was more expensive than the lead solder, which was itself quite
    expensive.  So plumbers gobbled up all the lead solder they could,
    before transitionaing to the higher cost of the "silver" solder.
    
    One of the worst side effects of the old lead solder in house plumbing
    is that it causes old age.  Look at all the old people out there who
    lived their lives in houses riddled with lead soldered copper pipes.
    Thank goodness we have the government protecting us from that fate.
    

>     One of the worst side effects of the old lead solder in house plumbing
>     is that it causes old age.  Look at all the old people out there who
>     lived their lives in houses riddled with lead soldered copper pipes.
>     Thank goodness we have the government protecting us from that fate.

	Just what we need, lots of old people with dementia .....

	Bet they said the same thing about abestos .....

> Boston, NYC, Philly, Chicago... all have solid lead pipes providing water
> to millions of people daily. They've been there for a hundred years in
> some cases.
> 
> Use your worry energy for the traffic.

Actually, that may *explain* the traffic in those cities...

How do they get the water through those solid lead pipes?  Do they use a
water chipper?  Will it improve the flow in hollow pipes as well?

    .12 partly answered the question, but what is the composition of the
    'new and improved' lead-less solder? What is that 40% of the volume of
    lead replaced with? Better not be silver!

Antimony I think.

(which makes me wonder how long until we hear about
antimony contamination of our water - it's a chemical
cousin of arsenic)

    No, it's more like 95% tin, 3% silver, 2% antimony...or whatever.
    

    If it's 95% tin, what does that then do to the ease of sweating copper?
    That much tin should take a lot more heat to get the solder to flow -
    possibly more that a standard handheld butane torch can handle ( heat
    dissipates too quickly).
    
    And more to the point, how much of a problem is it really if 40% lead
    solder is used on a supply pipe? At what rate is that lead dissolved?
    If it is indeed really being dissolved, how come all the copper pipes
    in the world which have lost all their lead are not leaking from all
    their soldered joints? How much water do I have to drink in
    order to match the amount of lead that I am ingesting simply by
    breathing, eating high-food-chain consummables, or occasionally gnawing
    on a piece of painted molding? 

    Whatever it is...it's pretty easy to use.  It flows well.  I'm inclined
    to think it flows even better than the old tin/lead alloys.
    
    

And those torches are propane, not butane.

Its made of of 95% tin 5% Antimony - well at least the stuff I used was...

re .19:

I think the melting point is a little higher than lead solder
not too much worse.  Seems about the same to work with.

Lead (plumbing) solder wasn't optimized for minimum melting
point anyway.

-Mike

    In the proper proportions, it's possible for an alloy to have
    a melting point lower than any of its component metals.
    
    					andrew

>    In the proper proportions, it's possible for an alloy to have
>    a melting point lower than any of its component metals.

This is true for solder, both the lead-tin and the tin-antimony
versions.

Another example is Wood's Metal which melts at substantially less than
the boiling point of water.  Used in fire sprinklers.

-Mike

Wow, what an incredible amount of information. Thanks to all!

I am constantly amazed at the quantity and quality of responses provided
in Notes. 

Thanks again!

d.t.

FWIW I think the danger of contamination from the small amount of electrical 
solder I used is minimal. So I will probably not redo the joints in question.
I just hope I don't start second guessing myself every time my kids get a bad 
grade on a math test 8^) 

95/5 tin-antimony solder IS harder to melt than 60-40 with a propane torch.
I find that it takes longer to heat a simple elbow or tee to the melting 
temperature of the solder for good all-around-the-joint flow with lead-free,
but it eventually works.
I do have more trouble with heating larger metal masses, notably faucets.
I destroyed the plastic ball in a ball valve because I could NOT heat the joint
area to temperature without having the heat dissipate through the metal
mass of the valve body.  (I don't think those things disassemble to avoid 
this problem, do they?)
Acetylene works great, however, but I've only ever had a chance to use one 
(borrowed) once.

- tom]

    
    Berzomatic now sells a torch kit that can use either propane or Mapp
    gas.  The Mapp gas burns much hotter (similar to acetylene).  A simple
    nozzle change (included) on the torch handle is used to switch between
    the two.  One can even braze with it.  It makes short work of even the
    most stubborn connections.  Mapp does tend to cost about 3-4 times as
    much as propane, however.
    
    

    also, you need to use the flux that is designed for the tin/antimony
    solder for best results. 
    
    ...tom

    
    One of the carpenters that is doing over a room in the basement hit
    a copper pipe with a nail, causing a leak.  The leak was fixed with
    a sleeve.  Since the pipe is a water supply pipe, I asked if the solder
    used was the leadless kind.  The answer that I got was "yes", however,
    I am skeptical.  Is there any way to know for sure without taking the
    sleeve off and having a plumber re-do the repair with leadless solder?
    I thought of testing the water, but if lead from solder leaches out
    over time, I could test the tap water now and not get a lead reading.
    
    ems

Even if it is the old 50/50 lead solder - one joint is not going to do anything
even if you sat under the faucet and drank from it for the rest of your life
(of course IMHO).

If you really want to know - scrape some of the solder off and take it to some
sort of lab - the cost is most likly not worth it.  If you want to make sure it
isn't lead-based - hire a plumber to re-do it. 

What makes you skeptical about the contractor's answer?

bjm

    You can but lead testing sticks at many hardware stores.  They're a
    couple bucks.  You break a couple of glass vials inside a cardboard
    tube to mix some chemicals, then wipe the wick end of the tube on
    the suspect material.  If the wick turns red, there is lead present.
    
    But I'd agree with .31, don't worry about it.

Re: .30

	Unless the carpenter had some solder leftover bought many years
	ago the solder should not contain lead.

	The same with paint...........

If it was an electrician, I'd be suspicious.  But why would a carpenter have
lead-based solder?

    
    Thanks for the responses.  I am going to have the solder tested.  
    
    The reason that I am skeptical is that I have been lied to on many 
    occasions by builders and contractors.  Not everyone does good work,
    unfortunately.  In instances where I have trusted the contractor, and
    the contractor was deceitful, it cost me money to fix.  I don't just
    want to pick on contractors, I also had a bad experience with a lawyer
    and a surveyor, which ended up costing me $1000 to resolve.  I couldn't
    prove negligence.  I also, have had very good experiences with
    contractors, but I feel that I have to question anything if I want to
    make sure that I get a good job done.
    
    As for lead, I have had to go through a lot of issues dealing with lead
    paint, and I definitely do not want to deal with any lead issues
    whatever, no matter how insignificant, so I am going to have the solder
    tested.  Small children can not tolerate small levels (I don't know
    what they are) of lead, so since there will be babies residing in the
    house, I do not want any lead solder in any copper pipes that source
    the drinking water for the house.
    
    ems
                                                                    

    The point others were making was this:  even if the solder had been
    pure lead, there isn't enough there to cause lead poisoning.  The
    amount of lead (assuming it's there) that would get into the water
    would have to be measured in parts per trillion.  You're in more
    danger from cosmic ray particles altering your DNA.
    
    					andrew

    Improvised solder flux:

    I had collected all the pipe fittings etc. that I needed for a home
project only to find out I had no paste flux.  Knowing that some sort of
flux / anti-oxidant is required to sweat copper joints I racked my brain
for a substitute I might try.........  Vinegar? .......... BakingSodePaste?
..... Navel Jelly?!?!?!?

    I tried the Navel Jelly and was pleased to find that it works just as
well as paste flux!  There were no real fumes and the solder "flowed" into
the joints as well as if I were using the "real" thing.

    Now I wouldn't recommend this substitution for constructing a domestic
service line (without polling the manufacturer first...) but for other
applications (or in a real pinch) it's a viable solution.........

- jw

    I need to replace a section of 1/2" copper tubing.  Will compression
    couplings hold well enough?  
    
    	thanks.
    	helge.
    
    ...the reason I am replacing this copper tubing is that there is one
    section where the tubing has turned green from corrosion, and the water
    is ever so slowly seeping out through this one area and dripping on the
    basement floor. I figure in time (hopefully not before I fix it) this
    "seeping" will turn into spraying and steady flowing.  Is this normal
    for copper tubing to corrode like this?  There is no visual evidence 
    of damage to the tubing other than the green corrosion, no cracks, no
    dents, etc.  It is along a straight section, not a corner or bend or
    joint.  

You can buy special "repair kits" which use compression couplings.  They
hold up ok, if installed properly.

			Steve

    re:175
    
    	Is there any reason why you don't want to just cut out the bad piece 
    and solder in a new piece ?
    
    	Ray

    re: .177 -  I don't have the tools.  I could buy the torch and solder
    and sweating materials and whatever else is needed, but I figure I
    won't need them after this repair (hopefully anyways) so I figure 
    the compression couplings or repair kit maybe the more practical route.
    
    That and the fact that I have never sweated a joint before (nor have I
    ever inhaled...8^)   If soldering/sweating is far better than I may
    decide to go that way, if the difference is small, than I may just
    stick with the comp. coupling plan.  Ideas/comments from past
    expeerience?
    
    
    	helge. 
    

    Compression fittings will certainly work, but they are sometimes
    finicky.. 
    
    you'll want to make sure your cuts are square (use a tubing cutter if
    you can), and that the outsides of the pipes are clean before you try
    to assemble the fittings..
    
    ...tom

    We just had a plumber repair one of those pinhole leaks. Turns out he
    had to replace about 20 feet of tubing since the corrosion wasn't
    limited to just the spot with the obvious leak. 
    
    I know how to sweat a joint and have the tools, but I wouldn't do it
    myself since I was unsure of the extent of the corrosion. I think it
    cost about $120 or so to get this done. I'm far more comfortable
    knowing it was done right and that I didn't waste my time patching
    something that was only going to open up again somewhere else.
    
    If you attempt this yourself and use compression fittings, they should
    work. At a minimum I would invest in a small tubing cutter to make sure
    you get perfectly squared off ends. If you use a hacksaw to cut the
    tubing, you may be chasing more small leaks.
    
    Good luck.
    
    Art
    

Sweat it.

The costs are competitive.
I want to say it's a wash, but that's probably only close to true.
You can buy a propane torch kit (gas, nozzle, lighter) for probably $10~$12.
A small spool of lead-free solder will probably be $5, less if you can find
a small amount.  Flux, a buck for a small tube?  Emery cloth or a wire brush,
maybe fine sandpaper - you may have that already.
You'll need a tubing cutter for either job, as cheap as $3, say $6
for a compact jobby.

So we're under $20 for tools, add 20 cents apiece for coupling sleeves.
You can probably beg a short lebgth of tubing from somebody, or buy a 10'
length and use the other 9 1/2 feet for ivy.

How much as compression fittings, and what have you got left when you're done?
The torch kit and solder and flux will be good for lots of other jobs,
yours or a friend's.

Soldering is REALLY EASY!  Dave Barry has called it the miracle of the ages
(look up his real estate adventures early in the Dave Barry notes files).
Well, it is harder with lead-free than with 60/40, but it's still readily
doable with propane.

Go for it.

- tom]

    Add in the cost of a fire extinguisher....
    
    If you've got corrosion in one place, odds are that the pipe is too
    weak to deal with compression fittings. Solder in a new chunk of
    pipe...
    
    CHris
    

    	The $20 is probably pretty close. Sweating a pipe is not a
    difficult skill to learn. For the investment of a little extra time,
    you can pre-tin the pipe ends which almost guarentees you'll get it
    right the first time.
    
    	To do this, clean the pipe ends with emery cloth, apply some flux,
    heat the pipe ends till solder will readily melt on the pipe ends.
    Apply the solder and wipe with a clean damp rag to get a nice shiny
    even coating of solder. Apply it to about 2" of the pipe end.
    
    	Next use emery cloth to clean inside the couplings, apply flux to
    the inside of the couplings, assemble the pipes, heat the joint until
    solder will flow into it. Give it a couple seconds then use the damp
    rag to wipe excess solder/flux from the joint. It's that easy.
    
    	The biggest thing is to make sure that the original pipe is
    completely dry in the area you're doing. Even a drop of water can cause
    problems. You can also use Mapp gas instead of propane. It burns a
    little hotter and seems to make the solder flow easier.
    
    	You probably need to find out what caused the problem in the first
    place. I've heard of houses that have acidic water, and that in rare
    cases, it eats the pipes from the inside out. This will be more apparent
    when you remove the bad section. Barring that being the problem, you need 
    to inspect the area and see if you can isolate the cause.
    
    	Ray
    
    BTW - There's nothing wrong with the compression fittings. I just tend
    to think of them as more of a temporary fix rather than a permanent
    one. I'd think that they'd be more subject to leaking if there's any
    vibration/movement of the pipe.

    RE: .- a few
    
    I would hazard a guess that the pipe in question here is a heat pipe. 
    That being said, a compresion fitting might not work.  Heating pipes
    are traditionally thinner walled pipes.  If you are having a leak,
    chances are that the pipe walls are also partially corroded and
    weakened.  A compression fitting here will probably leak fairly
    quickly.  I'd suggest that the root cause of the leak be investigated.
    If it started from a pinhole in the pipe, then replacing that section
    should do it.  If the problem is acidic water, then further work should
    be done to prevent further damage.
    
    Dan

    re: last few...
    
    First, thanks to all the replies/suggestions.
    
    The pipe is a cold water pipe.  I am guessing the leak was caused from
    the outside, the first floor tub is directly above this pipe and
    apparently this tub had leaked for quite some time, a slow leak dripping
    onto this pipe in the basement.  When we bought the house, I remodeled
    the bathroom and eliminated the leak.  Now it seems after time, the
    corrosion has slowly deteriorated the copper pipe.  So I *think* that
    this is an isolated incident.  For now I have shut off the flow to this
    part of the pipe which just happens to be towards the end of the line
    anyway, feeding the cold water supply for the washer and branching off
    to an outside faucet.  I'll stop in at Home Depot on my way home (just
    happens to be ever so conveniently located just down the road from my
    house) and see what they've got to say as well.  
    
    	thanks again.
    	helge.     
              
    
       
                 

We had a copper water pipe (not a heat pipe) develop pinhole leaks such as
described.  The whole length of the pipe developed pinhole leaks all along
its length pretty much at once.  Acid water can do this.  I'd suggest the whole
length of the pipe be replaced, not just the leaky section.

Another handy thing for the home pipe fixer to have is a pad that goes between
the joint being soldered and flammable walls etc. to keep from igniting them.
I don't know what they are made of, it's not asbestos, appears to be fiber
glass or something.  HD type places should have it.

Also it is absolutely essential to have the joint being soldered be absolutely
clean and dry.  Keep this in mind and it's not hard to solder.

    Another way to save yourself some grief: when you shut off the water to
    this pipe to replace the leaky section, don't just shut off that
    segment.  Shut off the main valve for the whole house.  If you have
    acidic water anyhow, chances are the branch shutoff valves are corroded
    too, and if you try to use one, after you are done with the pipe and
    turn the water back on, you'll find that the shutoff valve is now
    leaking, and you'll have another plumbing job to do right away in
    replacing the valve...  Guess how come I know this?  You got it!  And I
    wasn't even smart enough to learn after the first time I had to replace
    a shutoff valve after fixing something beyond it, so now BOTh the
    bathroom AND the kitchen have new shutoff valves too.  We got smarter
    on the bathroom ones and since the valves had to be replaced anyhow, we
    instead soldered in fittings and got the kind of shutoff valves that
    screw into the fittings, so next time the valves wear out, they can
    just be replaced (no torch needed).
    
    Save the local shutoff valves for dire emergency use only.
    
    (Doncha just love living in an older house...???)
    /Charlotte

I always use ball-valves when replacing shutoffs.  I think they're much more
reliable in the long run, especially when used infrequently.

				Steve

    as a follow-on to the ball-valve point: if your main shutoff is a
    standard valve, and it hasn't been shut off in along while, be prepared
    to have it snap off in your hand or otherwise give you grief.
    
    ...tom

> I always use ball-valves when replacing shutoffs.  I think they're much more
> reliable in the long run, especially when used infrequently.

	Or when used frequently ball-valves are heaven for those of us
	in the computer industry that have repetative stress disorders
	in the wrists (or for even those that don't, ball-valves are
	still much easier to turn on/off with a single flick of the
	wrist ....).

	And don't forget to get ball-valves with drains if you are
	replacing shutoffs with drains.

	And myself I prefer to always use full-port ball-valves when the
	price difference is minimal (but make sure to ALWAYS use full-port
	valves for FHW systems).

    Do you have solder fittings already containing the solder in the US ?
    They are commonly available in the UK. There is a ring of solder inside
    the fitting, so you just need to clean everything up, use a bit of
    flux, assemble and apply heat. There is just the right amount of solder
    to make a nice joint without excess solder running out of the joint.
    The drawback is that these fittings are a little more bulky than the
    plain fittings, as there is a 'bulge' where the solder ring was.
    
    Andrew

    re: .191
    
    I've never seen any here, though that doesn't necessarily mean they
    aren't available, somewhere or other.
    

    The main shutoff valve in my house gets used maybe once a year (when
    flushing out the hot water heater, or when fixing a pipe someplace), so
    it always works right.  It's the cheapie little individual shutoff
    valves, which may not have been turned in 25 years, that break on me.
    After spending most of a weekend day one time trying to repack one of
    those, and ending up replacing it anyhow, I don't even try them
    anymore.  Sure, if there was a sudden plumbing emergency, I might shut
    one of those off if I couldn't get to the main valve, but anymore I
    just assume that if I use one, I get to fix it too, so that's a pretty
    good disincentive.  I don't really like doing plumbing; it's just that
    paying someone else to screw it up and leave a big mess for me to clean
    up anyhow isn't very cost-effective (yeah, I know doing your own
    plumbing is technically illegal in this happy state).  Steve's probably
    right about replacing the darn things with better valves if you have to
    replace one - as I said, we replaced them with screw-on valves so that
    if they have to be replaced again no soldering is needed.
    
    /Charlotte 

     I would never pre-tin the fittings because of the possibility of them 
not fitting together with solder on them.  [US fittings]

     To make sure the entire joint is hot enough to take the solder:  
apply the heat to the 'front' of the joint and touch the solder to the 
top 'back' of the joint.  That way when the solder melts, you know the entire 
joint is hot enough for the solder to run into it.

     The special material used between the pipes being worked on and the 
flammable wall behind them is called aluminum foil.  Two thicknesses are 
usually enough.

    Cement board will work as an insulator as well, even a scrap piece of
    wall board will work.  HQ and Home Depot have handy hint pamphlets for
    any number of DIY projects including sweating joints.  Most of the DIY
    books like the Reader's Digest or Better Homes and Gardens repair it
    yourself guides also have instructions.  It is one of the more daunting
    tasks to undertake at first glance but, in reality, it is quite easy to
    do and can be one of the more satisfying (money saving) skills to
    learn.  My $0.02. 
    
    Brian

>      The special material used between the pipes being worked on and the 
> flammable wall behind them is called aluminum foil.  Two thicknesses are 
> usually enough.

	That may work if you've got a good distance between the joint being
	soldered and the flammable surface, but in those cases I simply
	use a spray bottle and moisten the flammable surface.

	For soldering in places where it's close to a flammable surface
	aluminum foil will burn that close to a propane touch flame
	(I've had aluminum foil burn when it's too close to the heating
	element in just a toaster oven).

	The special material as a previous noter indicated appears to be
	a tightly woven fiberglass yarn pad.  It's recommended you moisten
	the pad before use, and it does work very good.  You could also use
	a piece of scrap sheet metal, but unlike the special pad, the sheet
	metal will conduct the heat to the other side which could still start
	a fire it the temp. reaches the flammable surfaces flash point.

When I was thinking of doing major plumbing I thought about having them
shipped over, sure makes the job alot easier/quicker, as it saves having to
hold solder/flux brush etc, I never had to redo one either. I cant think
why they are not used here.

In the end I went with CPVC so its moot, but anyone know why you cant get 
then here, I'd never seen a copper joint without the solder until I arrived 
here

> When I was thinking of doing major plumbing I thought about having them
> shipped over, sure makes the job alot easier/quicker, as it saves having to
> hold solder/flux brush etc, ....

	Regarding a flux brush, I found them a pain.  Much easier/quicker
	to use ones finger(s), IMHO.

> I never had to redo one either.

	And most don't have to redo the standard solder joints either :-)

> I cant think why they are not used here.

	My guess would be $$$$

Dont know what the price difference is since in the UK they are (or were :-) )
universal - and used by professionals too -, but since couplings are already
formed adding two extra groves is 0 factory cost, solder cant be that much
extra.

They can also be installed one handed, leaving the plumber free to collect
the $ with the other. Having seem Rich & Norm and there "Its a bit
more expensive but well worth it in time saved " slogen on just about
everytyhing I thought there may be another reason. 

Maybe as soon as the novelty wares off the "Euro style" hinges they keep
refereing to as an upmarket cabinet feature, which can also be found on the
cheapest British cabinates, they'll try these "Euro joints"

>> I never had to redo one either.

>	And most don't have to redo the standard solder joints either :-)

I'm sorry you did not build my house :-)

I've had to redo about 5 that were installed when my house was build. When
I take them apart and look at the solder the seal is nowhere near as uniform
at those with solder preinstalled, and in places was to thin it lead to the
leak, ok so the acid water helped.

    re:194
    
    	This is exactly why I didn't mention pre-tinning the coupling, as
    it is easy to get a drip which won't allow it to fit together. The pipe
    ends themselves allow easy access with a damp rag however, and even
    someone doing this for the first time can get a good, thin, even
    tinning.
    
    	It also gives an immediate indication as to whether the pipe end
    was properly cleaned and fluxed. If the tinning doesn't take, you need 
    to wipe off the flux, re-polish the area with emery cloth, re-apply the 
    flux, and try again. If it didn't tin properly, there is a high probability 
    that this joint would have leaked if soldered without the pre-tinning.
    
    	Ray

> ... but since couplings are already
> formed adding two extra groves is 0 factory cost, solder cant be that much
> extra.

	The basic copper couplings are a relatively low cost commodity
	item produce in volume.  *Any* additional manufacturing cost
	adds up fast when you are talking high volume (just ask the
	auto industry).  And your assumption of $0 cost for adding two
	extra groves is unrealistic.  First you are talking about re-tooling,
	and second, not having seen the type of grove needed here, it could
	be an extra step after the initial forming of the part which if
	it even adds a fraction of a second, again adds up due to the volume,
	and reduces overall output.  Same factors go into the cost of
	adding the solder which is most definitly a 2nd step.

	Also take a look the next time you are at HD or HQ, if I recall
	correctly (my memory is not what it used to be :-), there was
	a price difference just between the basic straight coupling
	with a stop and the one with out a stop.  What I most definitly
	can't remember is which one was more expensive, because the other
	factor in cost is the volume (the lower the volume the higher
	the cost).

> Having seem Rich & Norm and there "Its a bit
> more expensive but well worth it in time saved " slogen on just about
> everytyhing I thought there may be another reason. 

	Don't assume Rich & Norm are the "norm" (pun intended).  TOH is
	notorious for getting the homeowners to go WAY over budget (after
	all, it's not TOH's money).  And TOH likes to showcase new products
	(I wouldn't be surprised if the producers or Rich & Norm themselves
	got kickbacks).

> I've had to redo about 5 that were installed when my house was build. When
> I take them apart and look at the solder the seal is nowhere near as uniform
> at those with solder preinstalled, and in places was to thin it lead to the
> leak, ok so the acid water helped.

	If it's the water, then only time will tell if the same thing will
	happen to the Euro couplings.  In either case, it could also be the
	plumber who did your house either didn't know what they were doing,
	or cut a few corners to save on materials and time (which is very
	likely if your house is in a development and built at the same time
	as other houses, and the same plumber was sub-contracted for all
	the houses).  Us DIYers on the other hand take the time to do each
	joint correctly :-)

    I would certainly not rule out poor joints because of an incompetent
    plumber.  Based on joints in my house, and a couple of alleged
    "professional" plumbers I've seen in action, there are indeed
    many plumbers out there who don't have a clue how to do a solder
    joint properly.  The pre-soldered fittings may be more idiot-proof,
    but there is absolutely no difficulty in doing good joints with
    separate solder and flux if one knows what one is doing.  (And
    if one doesn't, it's well-nigh impossible....)
    

re acid water and holes in pipes:

some years ago, it was forbidden to use solder containing lead in
water systems.  most of the housing stock was constructed before that
happened.  acid water can dissolve detectable quantities of lead
out of the solder. it can also dissolve copper. the reaction with
the copper quickly forms a thin film that largely prevents the
reaction from continuing.  that does not happen with the solder.
thus the common advice to run the water to flush the pipes before
drinking any of it each morning.  

the EPA and the state equivalents have carrots and sticks for
water supply districts.  they measure the lead content of water
at the faucet at any time they choose, which just happens to be
first thing in the morning.  if they find too much lead at too many
places, they beat the district with the stick and the district
raises the rates to pay the fine.

to avoid this problem, many water districts add buffers to the water
so the water that sits in the pipes is no longer acidic.
your pipes may last longer this time.

this is about the u.s.   other countries may have done this earlier or
later or partially or not at all.

also, don't panic if you realize you forgot to run the water before 
drinking it.  each lead atom does some damage, but the total in
most homes will not result in any symptoms over a lifetime.