Conference vmszoo::rc

    I'll make a deal with you...  I'll supply the fan if you let me use the
    place...  I have the fan unit from my old furnace that I have been
    saving for when I have a basement.  It moves a lot of air, but that can
    be controlled by vents.
    
    You would probably want a couple of speeds on the motor as well..  When 
    you are spraying, you want to move the particles out.  When it is
    curing, you just need to keep the odors down.
    
    You will want filters on both the intake into the booth and the
    exhaust.  
    
    Now, here is the real catch...  Heat...
    
    You need to keep it warm...  But, if you are moving lots of air out,
    you need to put lots of warm air in.  If you have a forced hot air
    furnace, can you divert some air into it?
    
    I also have a compressor that I can loan to the project if you don't
    have one..
    
    Cheers,
    jeff
    

                                     
    
          Jeff, 
    
              You can use the booth if you need it anyway, thats no problem.
    
               The furnace fan sounds like a good idea. ducting should not
               be any problem either. I am planning to pick up the lumber
               and sheetrock today at Home Depot, so I will look around
               regarding fans/ducting to see whats available.
    
           Re: Heat. This is something I haven't solved either. I have a
               forced hot water system in the house, so ducting wouldn't
               work. I have a 1500 watt ceramic heater that would easily heat
               the space, except the fan would suck all the heat out. I
               will probably try to figure out how to utilize it anyway.
               The process may be to preheat the area, keep the heater
               on, turn the exhaust fan on high, spray, turn the exhaust fan 
               to low, and hope I can maintain reasonable heat.
    
               The good news is that heat isn't an issue in the summer, as
               the basement usually maintains 65 degrees +.

The fans for a bathroom aren't going to move enough air through the little duct.
You need an AC fan or Jeff's furnace fan and a full window. Be careful with
lighting/fans in the booth since the atmosphere will be explosive. Best to make
the booth so the lights are behind the plastic shining in. Talk to Henderson
since he made a portable one that fit into his cellar bulkhead. The other
solution to the fan speed (sparying/drying) is to have a heated, venter drying
area separate from the high capacity fan painting area.

Jim

    
                                          
         Jim,
    
            Thanks for the info on the fan, although I am confused, because
       if a bathroom fan is rated at (x) CFM, shouldn't it be able to move
       that much through the standard ducting its connected to? I quess the
       real question I still have is: what CFM do you need in a 224 CF
       booth?  The bathroom fans range from 30 - 300 CFM, so what I was 
       wondering is if the high volume versions would work ok?  Regardless,
       I will check into the furnace fans.
                                                                
            Your tips about the lighting are interesting, but wouldn't the
       fan motor create as much of a hazard? Or is it the heat the light
       bulb or heater element generates that creates the potential
       explosion problem? 
    
            I talked to Bob Brodeur, and he build a paint
       booth once, and just used a bathroom fan, and mounted 4 lights in
       the corner of the booth, and he said it worked fine.
    
            I already tried calling Eric for his input this morning, but
       no answer at home ( probably out flying :), I will try again later

Charlie was interested in a booth as well and talked at length with Eric about
it. I have an old air conditioner fan expressly for this purpose. Remember that
the filters are going to cut down on your CFM rating some. I vented my cutter
recently and the best bathroom fan I could find at the local store was 50cfm and
it's marginal (for just foam cutting fumes). Granted the cutter has been running
16 hours a day recently but it's tough getting it all airtight and such. I'll
try to scare up Eric's discussion on how he did his...

                                    
    
       I talked to Eric on Friday and tapped his spray booth experience.
    He recommended a few things that changed my thinking around regarding
    the construction. He recommended the following:
    
         1. Use plastic, not sheetrock ( cheaper )
         2. Use a standard 18" by 18" house fan ( 2 speed ). He reminded
            me that you need to move a LOT of air SLOWLY to make the booth
            work properly, and this type of fan was a good way to go.
         3. Make the ducting from the fan to the outside out of plastic, 
            not metal ( cheaper )
         4. Use cardboard boxes to change the direction of the plastic
            ducting ( if needed )
         5. Use screen on the entire "intake" side of the booth to keep
            dust out, etc.
         6. Mount the fan in the wall opposite the "intake wall to allow
            for smooth airflow.
         7. Use 2 by 4 constuction for the booths frame.
         8. Use incandecent indoor "spot lights" in each corner of the
            booth ( both for lighting capability AND heat generation )   
         9. "Crack" windows in the house to allow adaquate aiflow through
            the booth.
    
    
         After talking to Eric, I got down to work. I was trying to figure
      out how to make everything work in the basement location, when it 
      dawned on me  that I still have an unfinished bedroom upstairs which 
      I don't plan to finish for another couple years. Since I no longer 
      have the "benefit" of a wife to tell me NO!, I immediately 
      requesitioned the space. The "bedroom" location solved both the 
      ventilation problem AND the heating problem for the booth. I will 
      eventually move the booth to the basement, but this will give me a
      chance to try different ideas ( layouts, ducting, fans, etc) while
      already having a booth to use. 
         Next step, I took a trip to Home Depot to get the supplies. I also 
      got lucky when I stopped at the Nashua Recycle Center, and found an 
      old storm door at the "swap shop".
     
         By 5:00 on Friday afternoon, the space was cleared, and
      construction began ( details to follow ).
    
                                              
       

2 more things to consider.

1.  Sparks - everyone suggests that you make sure the motor is one that does
    not produce sparks.  I have no idea how to make sure of this and I myself
    use a bathroom fan which I hope is sparkless but don't know.

2.  Furnace safety - there is a long string in the woodworking notes file
    about dust collectors and the reason they collect in the house (shop)
    instead of outside is if you move too many cubic feet of air outside
    you will screw up the draft of the furnace and pump carbon monoxide
    in and die!  Also there is the issue of pumping warm air outside and
    having enough furnace capacity to replace that much warm air.

Bye          --+--
Kay R. Fisher  |
---------------O---------------
################################################################################

    
    
       Over the long weekend I managed to build the entire booth ( didn't
    take that long), AND used it to respray my Heli canopy.
    
    Construction:
    
     - I laid out a 8 by 6 floor with spare plywood. The room I built
       it in is totally unfinished, and the joists are still exposed on the
       floor. I initially laid out a 8 by 4 area, but determined it would
       be too small to operate in.
    
     - I used 2 by 3's for most of the construction, mixed with a few 2 by
       4's. I ended up purchasing (12) 2 by 3's and (4) 2 by 4's.
    
     - The floor and all the walls were constructed with 2 1/2" drywall
       screws. This will allow for quick disassenbly in the future.      
    
     - I used 4 mil plastic for the ceiling and the walls. I ended up using
       about 75' worth of 10' wide plastic. I decided to cover both the
       outside and the inside of all 4 walls. Covering the outside was
       probably overkill, and is probably not needed.
    
     - I mounted the fan in the back wall, 36" from the floor directly
       across from the storm door. I taped a furnace filter to the front
       of it to capture paint particles. I  made a short tunnel ( 2
       feet long) out of plastic, taped one end to the back of the fan, and
       the other end to a 16" by 16" box ( with both ends removed ). When
       I use the booth, I simply open the window, remove the screen, stick
       the open end of the box out the window, and then clamp the window
       shut on the box.
    
     - I mounted the storm door, removed all the inserts from the door,
       and replaced the inserts with (2) 24" by 30" furnace filters to
       filter the intake air.
    
     - For lighting, I purchased (2) work lamps, and installed 100 watt 
       indoor spots. They seemed to work fine, but I may upgrade to (4)
       spots when the budget allows. Another upgrade would be to go to
       150 watt spots. 
    
     - As the last step, I made a short (4 ft) plastic tunnel from the
       door leading into the "bedroom" to the storm door. This helps direct
       the warm air from the house, to the booth without loosing heat to 
       the rest of the uninsulated room.
    
    
      Operation:
    
       1. Open door from house to room to preheat area. I also supplemented
          this with a 1500 watt ceramic heater placed right outside the
          storm door which I kept running throughout the painting process
       
       2. "Crack" windows downstairs to allow for airlow
    
       3.  Postion work (ie canopy, fuselage ) to be sprayed in booth
    
       4.  Place the box end of the exhaust tunnel in the window
    
       5.  Close storm door, put Respirator on, turn fan to high, and
           spray.
       
       6.  When spraying is complete, turn fan to low to exhaust vapor and
           minimize heat loss. 
    
      
      On the first try, it worked fairly well. I probably need to do a
    couple upgrades regarding airlow, etc, but I now have a resprayed
    X-cell canopy ready to go. Total constuction time for the booth, about
    6 hours, and so far I am very pleased with it.
       

    Re: the fan.
    
    A friend who had installed a vent fan in his shop to remove paint spray
    told me it is a law that you have to use an explosion-proof fan unit. 
    These are specially made (read expensive) units that won't cause an
    explosion when moving volitile gasses and fumes.
    
    Please be careful with ordinary commercial fans as they might not be
    the safest things for this.
    
    Other than that, it sounds like you've arived at a very nice solution
    to painting.
    
    On a separate note, I did some painting over the holidays using Black
    Baron canned spray paint to redo the Extra 300 cowl and wheel pants.  I
    don't have a respirator, but do use one of the cheap dust masks.  After
    two days of painting, I developed a severe headache that wouldn't go
    away even with aspirin.  Could be that I got "drugged" from the fumes,
    because they are awfully strong.  I think the next thing I get is a
    good respirator.
    
    Regards,
    Joe 

                                                                  
      Joe,
    
         Thanks for the tip. As I won't have any additional need to spray
    for the next few weeks, I will check into the fan situation more
    thoroughly. In the mean time, The booth can also double for a sanding 
    booth ( as long as I wipe the booth down before painting again ) which is 
    what I need it for in the near future.
    
         While I am checking out fans, please buy a respirator! If I can
    get the fan thing straightened out, you are also welcome to use the
    booth to avoid any future headaches :)
    
                Pick your poison, explosion or brain damage :(. Now I know
      why Monokote is so popular! :)         
    
                                                               Dan
    
        

    
        I have been able to do more "fan" research over the past few days.
    
       The first thing I did was to check the fan I am using for any arcing
    during startup or while running. I did this by looking into the motor
    in total darkness and then starting and stopping the fan several times.
    There was absolutely no visible arcing during the test.
       I have also been told that if a motor is an "induction motor, it
    doesn't have brushes, and also doesn't arc. This is the same info
    I got from Eric. It is a possibility that my fan has this type of motor.
                                                                              
       Another point brought up during my research is that the 
    fan motor can heat up during operation, and become a potential ignition 
    source. The best I can put together is that motor heat is a potential 
    problem, but a distant second to arcing problems.
    
       At this point, I checked with two people who have spray booths to
    spray full size cars. In one case, the booth has a 24" "explosion-proof"
    fan installed at a cost of $300 for the fan setup. In the other case,
    the booth has a "whole house" fan installed at a cost of $50 - $75. 
    In both of these setups, the fan is driven by a belt, and the motor is 
    out of the vapor stream. The difference is the "explosion-proof" fan
    has a sealed motor.  "Explosion-proof"" fans run from $200 - $600
    dollars.
    
       Both people said that based on my type of painting, as long as the
    fan wasn't arcing, it shouldn't be any problem. This basically lines
    up with what Eric and Kay were saying. 
    
       My conclusion at this point, is I am probably ok with my current
    setup, but for an extra safety margin I will check into the "whole
    -house fan" setup. If they make the right size and capacity, I will
    likely change over to it for an extra margin of safety.
    

>       The first thing I did was to check the fan I am using for any arcing
>    during startup or while running. I did this by looking into the motor
>    in total darkness and then starting and stopping the fan several times.

Wimp! Take the fan out into the yard and put it in a big cardboard box and use a
windex bottle to spritz some gasoline into the box and close the top. Then plug
in the OTHER end of the 100' extension cord several times. This method provides
entertainment as well as getting rid of the fan if it's unusable... 8^) nothing
like a fuel-air explosion to let your neighbor's know you're serious.

Is there any way to rig the current fan to use a belt drive? 

Another possibility is to PUSH the air through the booth from the screen door
side. This keeps the fan on the clean, incoming air side and eliminates the
problem with no significant changes. I'd probably have the fan blow through a
furnace filter on the inbound side to prevent dust from being blown in.

    The problem with pushing air in is that then the booth has to be
    very well sealed.  If not, your fumes will escape through every
    path except the one you want!
    
    Cheers,
    jeff
    

    I think the main reason for using explosion-proof fans, other than
    safety, is insurance coverage.  If by chance something ever does let
    go, an insurance company would have no sympathy for someone who blew
    volatile fumes thru a fan that exploded unless the fan was rated for
    this duty.
    
    You also have to be careful of on/off switches for the same reason. 
    They DO spark, so if there are fumes getting into the switch, you have
    the same issue to contend with.
    
    Whole house fan motors may have internal centrifugal switch contacts
    that would also be susceptable unless the motor can be placed entirely
    out of the reach of the fumes.
    
    Work exclusively with water-based paints and all this is academic.
    
    There is no simple answer, but to be on the safe side you need to be
    certain that no sparks occur in the areas where fumes accumulate.
    
    Regards,
    Joe

    
         Well, if nothing else, this has got the file active for a few
     days! :)
    
     Jim, I will have to try your "vapor" test sometime :) :)  
    
         I have thought about placing the fan on the intake side and having
    it blow the stuff out the otherside. Apart from sealing the booth
    properly as Jeff pointed out, I think it would be tricky to get the
    airflow to "push" properly without creating swirling problems.
        
        The switches do spark, and this is another reason I have been
    turning the fan on prior to use and not switching it off for 1/2 hour
    after completing the spray job ( although I probably shouldn't
    continue switching it from high to low during the job.)
    
        The idea of the "whole house" fan IS to isolate the fan/electronics,
    including the switch. If this can't be done, then it probably isn't
    worth using. If it can be, it should provide a very good level of
    safety.
    
        The point about insurance is a good one, although I find it stran
    that several people I have talked to seem to be worried more about the 
    house, than me blowing myself up ( Hmmm, is there a message here :). My 
    acid ( or should I say "vapor") test is to make it reasonably safe for ME
    
    to inhabit the booth. If I can safely be in the booth, the house should :)

    I assumed (always very tricky) that your life insurance already had
    you covered for accidental demise regardless of whether you are explosion
    proof or not.
    
    Your house, however, is another issue.
    
    Regards,
    Joe
    
    

    re:  .16
    
    Joe,
    
    The insurance company probably would not pay off for life insurance
    sine they would calim Dan took his own life because he couldn't be
    sooooo du*b to put a paint booth in his upstairs bedroom.  :}).
    
    Anyway, this guy should break down and go to a paint shop and have his
    plain painted by a pro (we're only talking about money.  :}).
    
    Ollie

    
     And THIS abuse from the two guys that have been spraying inside their
    houses with NO positive ventilation! :). I think the fumes have got
    to both of you! :)
    
    Re: Life insurance - Its nice to know you guys REALLY care! :) 

    I think your all really over exagerating the fan/fumes issue.
    
    The only danger is when the fan is turned on and maybe off. The fan
    is going to be turned on "before" you start painting so there's no
    fumes present. Left on after painting most of the fumes will be
    sucked out so there's little danger when turning the fan off.
    
    So what's the worst than can happen......a little flash fire.....maybe
    some melted plastic....."maybe" some minor damage to the interior
    bedroom walls/ceiling......a few singed hairs......
    
    What's the big deal............8^)

    I painted my motorcycle once in a home made paint booth I built in my
    basement in the furnace room!...  Basically did whats been done here,
    with the exception of disabling the furnace and extinguishing the pilot
    lights in the furnace and water heater.  I'm still here, and the booth
    worked just great.  One word I can pass along...best to leave the
    cigarettes outside until your finished...assuming that you smoke.  Also
    you may want to minimize the amount of static causing clothing you are
    wearing in the booth.  If you stick to natural fibres i.e. cotton, you
    should be safe.  All the explosion proof fans and lights will do you no 
    good if in the middle of your painting, you draw an arc and end up
    baking everything in the room.
    
    
    
    
    Regards
    Rod
    

    
    or PAINT IN THE BUFF...............
    
    Watch that static.......8^)

    
    Steve, I revoke my offer to let you use the booth! :)

No, really honey, it's ok that it's blue...