Conference 7.286::home_work

    There is a series of "Forgotten Arts" books, one of which is _How
    to Build a Stone Wall_.  Since I have LOTS of stone, I figured the
    book would help.  It didn't.  
    
    The book suggests that you locate a particular type of stone that has
    fault lines.  It then describes how to open a fault into a crack,
    eventually separating the rock into two pieces.  The method involved
    one person holding a maul with a wedge shaded head on a fault line,
    while another person hammered on the wedge with a normal maul. That was
    the "easy" method.  (Sounded like a lot of work to me!)  It said not to
    bother using the rocks which had been rounded by glacier action because
    it is tough to build anything out of round rocks.  Guess what kind of
    rocks *I* have... :-( 
    
    The "hard" method that the author tried only once was to drill a series
    of holes using a star bit.  Then a wedge was driven into each of the
    holes...  Like I said, the easy method sounded hard!  This one sounds
    awful!
    
    
    John B. 

    I think it took Cheryl and I about 30 minutes to split a rock
    about 2 x 3 feet.  We were following a crack that went in an unknown
    distance, and using a (blunt) chisel and a 4 pound sledge.
    
    Dick
    

    I used to hear the old adage that back in the days when a laborer's
    work was worth $1 a day, a man that could build a stone wall without
    mortar could get $8 day.  I would think building a wall is more
    that just a lot of work.
    
    -willie

    Most metamorphic rocks have a `sheer' direction to them.  If you
    tap the rock along this plane, it will split in half.  There is
    a sledge-hammer type of tool shaped like the maul referenced in
    one of the previous replies that is used for this.  You don't have
    to `break' the rock apart, the repetitive blows will split it (just
    like bricklayers splitting bricks in half)

    
    I've also been told that the age old trick of heating the rocks
    in a fire and then pouring-it-over/dropping-them-into cold water will
    cause them to crack nicely. Probably not exactly where you want,
    but if you have a lot of rocks you should get a good assortment.
    
    							Mark
    

    Re .5
    
    	You need a very hot fire for rocks to crack that way.  And
    then you won't be able to lift the rocks out of the fire and
    into the water.  Fire also destroys the "nice" look of most
    rocks; that sort of weathered, green/greyish appearance.
    
    -al

    In my section of Pelham New hampster, we have lots of two to seventy
    five cubic foot rocks on or near the soil surface. We call them
    lawn potatoes and we cook them with a rosebud to break them up.
    A rosebud is a propane torch used in metal shops to heat and bend
    steel and is available from welding supply shops. A rosebud is a
    two foot long metal tube with a hose connection at one end to connect
    to a propane tank. The other end has a pin hole for gas supply and
    a torch head that resembles a rosebud, it is about two inches in
    diameter and open at the end. 
     
    A freshly dug rock contains a lot of moisture. this is boiled by
    the torch a forces the rock to crack. Cracking is hastened by hitting
    it every 4-5 minutes with a sledge hammer. This process creates
    nice wall building rocks with 2 or more flat surfaces. A freshly
    dug 3x3x3 rock can be reduced to rubble in about two hours. Rocks
    that are laying on the surface contain less moisture and cooking
    time is doubled or tripled for a similar size rock. Dryer rocks
    also tend to shatter into shards rather than cubes. Rocks must be
    completely uncovered for best results, otherwise the surrounding
    dirt will absorb some of the heat from the rock and slow the process.
    A four or five foot metal pry bar is used to level these potatoes
    into decent cooking positions. Heat should be applied to the center
    of the rock or at a seam, if one is visible, for best heating results.
    The standard size propane tank (100 gal or 100 lbs) costs about
    $30 to fill and will last about sixteen hours.
    

    Last week on "This (New) House," they demonstrated the cutting of
    a piece of granite for a stair landing.  The procedure was to cut a slight
    line into the granite with a chisel, drill a few holes along the
    line, and tap wedges into each a hole, a bit at a time.  Cut it very
    nicely.
    
    They made the surface of the granite less slippery by crazing it
    with a torch fed with water, kerosene, and liquid oxygen (according
    to the guy using it).  The water was to keep the torch from melting.
    
    __Rich

    If you are patient and it is winter, you can drill the rock with
    a few holes and pour water into them.  When the water freezes, it
    expands and will break the rock.  If you have a cracked rock, the{same
    procedure can be used to further split it.  You can use caulking
    if the water tends to run out.

    For you couch potatoes who want to work with lawn potatoes, get
    a masonary book.  It helps but those buggers are a pain to split.
    I had a lawn (to be) that had a bumper crop of potatoes.  I piled
    all the rocks down at the end of the driveway to build pillars at 
    the entrance.  Like so:
    				     
    				     ______
    				    /	   |
    				   /	   |
       		________________.*'	   |
    					   |
    					   |
    					   |
    		---------------------------
    
    To fix up the hole the builder plowed through the old decaying
    farm stone wall.    

    Any efforts to split the potatoes as recommended in the book met
    with mixed success.  That seems to be because the rocks I have are
    granitic in origin with no grain direction.  I learned that it was
    a lot easier to spend the time to find rocks with flat sides.  I
    have nearly completed one pillar.  After all that, I found out the
    secret that is used to build nice loose rock walls.  You put mortar
    inside where it can't be seen!  Well since the first pillar is a
    loose one the second will have to be the same.  I am not going to
    build that bugger over.
    
    Stan

    I have read 2405 "Moving granite slabs", looked for related notes 
    no luck......
    
    I am trying to "shape" the edges of some granite slabs to round them
    off, and I am not having much luck. I believe it is a matter of having
    the correct tool. What I have is pieces of granite curbing. The curb
    has a finished (when in place as a sidwalk curb) top. Actually top and
    bottom are smooth, whereas the sides are rough. I would like to use the
    slabe to build a granite bench adjacent to the garden for use, and
    appearance. Two 4' legs set 1/2 way into the ground, and a 4 or 5'
    piece for the "bench". The problem is the finished portion. I would
    like to "chip" it off, and end up w/ the finish like what is on the
    sides.
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    Well, not exactly as drawn, but I hope you get the idea. When I tried
    chipping the finished end w/ a masons mallet, the granite fractures in
    various directions. I tried a pointed chisel w/ no luch either. I am
    able to test different methods on the half of the leg portions which 
    will be below grade.
                                     
    I am trying to round off the finished edges to give it a more natural
    look. Is it a matter of the correct tool (maybe a broader chisel), or
    is it more technique, or a combo? I have seen a hammer w/ an odd end
    It looked like it was for chipping rock (ah ha).
    
    All advice welcome
    Thanx/Bob
    
    Do we have any experienced chiselers in the audience :^)  ?

They had a segment on shaping granite (or some kind of stone for a patio) on
This Old House a year or so ago.  The guy had some sort of chisel and hammer
and I think he scored the surface first.  My recollection is that the chisel
had a special tip on it and cost quite a bit of money.

Dave

    The TOH segment showed the stonemason drilling holes in a line,
    defining the line he wanted the stone to break on. He then inserted
    some wedges, which in turn accepted a spike of sorts. By hammering
    on the spikes, he got the wedges to spread and the stone to crack.
    
    Maybe if you drilled it at the proper angle and filled the holes with
    water, then left it outside???
    
    Why don't you just take your kids outside, show them the rock, and tell
    them under NO conditions are they to break the rock in the specified
    fashion? My nephews would have it broke in no time....:^)
    
    Edd

  I believe you'll need two hammers - a standard mason's and a facing. Use the
mason's to remove the majority of the edge, followed by the facing hammer to
smooth it.

  I have a book on stonemasonry which I'll check tonight to assure the above
since I've never attempted to shape rock (but the Irish in me, and the bountiful
rock crop harvested every spring here in New England, has prompted my building
several stone walls for amusement).

  Patrick

    The TOH showed how to cut rock slabs into smaller slabs.  I believe
    what the base note wants to do is shape the slabs he already has.  
    Drilling holes and using feathers and wedges in the holes will make a
    nice cut.
    
    I have not done this but watched some stone masons one time :^)  They
    used chisels and a mallet.  To round the edge they would chip off
    *small* pieces until they got what they wanted.  If you want to round
    the edge, I would place the chisel on the edge and chip up towards the
    slab side.   Chipping down from the slab side towards the edge side
    might shear off the end and you could end up with a shorter bench.
    

    I have tried stone sculpture once....in alabaster. also got to try a 
bit with granite and a _large_ air powered chisel.....The attempt with the 
chisel just about knocked me off my feet, but that is another story...

    For hand carving granite, which is very difficult, look for a store 
that has specially hardened toothing chisels. the chisel looks like a wide 
chisel with short, pointed teeth on it. You also need about a 2-5 lb mallet 
to hit the chisel with. Work slowly (5 mins fast work with a 5 lb chisel 
will convince you better than I can!) and try for small chips only a few 
inches long. you will not get a chip off with each hit, but rather work it 
so that you gradually weaken the stones granular structure and finally chip 
off a bit. It will not be impossible, but will seem like it at first. Keep 
moving the chisel along the line you want to chip off. It should flake off 
after a bit of work.

    The only store I know that carries the specially hardened chisels for 
granite would be Sculpture House in New York City. I don't have thier 
number but information will. They will sell all the supplies and stone for 
sculpting that you could want.

    Vic H

  I checked my source for stone masonry, and the following tools are described
to shape stone 

  A double face hammer, which weighs 20 - 30 lbs, is used to knock off pro-
jections. It resembles a common sledge hammer, except that the bottom of the
head tapers. Only use this for the roughest of work.

  A face hammer is used for roughly squaring stones preparatory to the use
of fine tools. It is wedge shaped and somewhat resembles a mason's hammer in
shape and weighs anywhere from a few to 15 lbs. The cutting end is used for
squaring. Angled blows will knock off large waste areas, and may be used
preliminary to a chisel and mallet.

  Axe or pean hammers, tooth axes, bush hammers, and crandalls, are all used
to dress the surface, but are probably of little use in your application,
unless you prefer a smoother surface or a particular pattern.

  A pitching chisel, similar to a mason's brick chisel, is used to make a
well defined edge on the face of the stone. Vic's advice is right on (except
my source recommends toothed chisels for marble and sandstone), if you only
plan to remove a small amount. Otherwise you'll be pounding until your hands
turn to a bloody pulp.

  I can mail you a copy of my reference, if you'd like. Better still, take a
trip to your local Rock of Ages headstone supplier, and pick his brain.

  Patrick

    One way that much rough shaping is done by quarries these days is with
    a TORCH! If they are making a rustic birdbath, as an exmaple where an
    exact circular bowl shape is not desired, they simply heat up the rock
    with a torch and it will flake off. You might try the same with a small
    oxy- torch or some such.

    Thanx for _all_ the suggestions, now I have something to go with.
    
    Sure is nice to have this wealth on knoweledge to tap into.....
    
    
    Happy New year/Bob

>    One way that much rough shaping is done by quarries these days is with
>    a TORCH! they simply heat up the rock
>    with a torch and it will flake off. You might try the same with a small
>    oxy- torch or some such.

    I have seen them cut granite up at Barre VT (Rock of Ages) with a 
torch, but they were putting "_massive_" amounts of heat on cool rock to do 
it. It certainly does work though.....

One caution of course, use FULL FACE protection, plus good coverage of your 
neck and down your front. The chips maybe sharp and potentially could fly 
some distance. I would guess you would need at least a MAPP gas torch to 
heat the rock quickly enough to accomplish what you want. Good news is, try 
it during this cold weather, it may work faster than during warm weather. 
Heat the rock good to get some splintering, then toss cold water on it when 
it is hot to crack some more off. the old guys used freezing weather to
crack the rocks for them after drilling holes and inserting wet sticks in 
them and allowing them to freeze. Don't know how effective that was, but it 
must have worked to some degree.

    Vic

    
    Hi,
    
    	Don't know if this is too late but here goes anyway....source
    for stone working tools: Bicknell tools, Rockland Maine. Give them
    a call. I don't have the number handy but information should have
    it. They supply quarries and rental shops with tools of this sort.
    They could at least direct you to a local distributor of their
    products.
    
    	My brother-in-law, a mason, cuts a lot of granite and that is
    who he gets his tooling from....
    
    Have fun!

    RE-.1 
    Thanx
    
    Bicknell Tools 
    Rockland ME
    207-594-8454
    
    Folks are very helpfull, and even referred me to a local company for
    mechanical type advice. 
    
    Thanx a bunch/Bob