Hi all, I was reading in a recently published book about painting your car yourself that you should use a box fan to draw out the volatiles/fumes, etc. from your 'paint booth' (i.e., on the ground at one end of the booth so as to draw fumes out) while you are painting. But isn't that a fire hazard? I have heard that any source of spark can ignite the vapors in the air, causing combustion/explosion. Certainly an electric box fan could generate sparks.
Is this a real danger, or am I being too cautious?
Also, what about using radiant heat lamps? How soon after spraying should it be okay to turn them on?
Mike

The only I would use a box fan to vent paint fumes is this......
Make Y shaped duct work,connect the fan to one of the upper legs sitting in clean outside air. Connect the other to the temp. paint booth.The long leg vents to outside air away from fan intake.

Maybe this was not completley safty concious, but.... When I did mine, I put a row of 5 box fans blowing out at the door opening of my garage, and covered the door opening with plastic, except where I sealed it to the fans. Let a lot of light in, which was a good thing, and the fans kept the "smog" down.

Note I did not blow myself up...

When I painted my 67 in my garage I used 2 box fans.
I used plastic sheeting that you buy from Home Depot
to cover the sides, ceiling and garage floor. I placed one fan above the garage side door to blow air in and the other fan below the garage door which I left open about a foot to suck the air out.
I painted the car on a weekday so I won't have to bother the neighbors. Also I used cheap AC filters in front of the fans. By the way it did'nt blow up.

I haven't built my temp. booth yet, but I plan to use positive pressure, i.e. blowing fresh air into the booth. Both the input and output air will be filtered. This eliminates the spark hazard that you speak of and also prevents dirt from being sucked out of the cracks and crevices around the car.

Wayne

I use a direct drive furnace fan and I haven't blown yup yet. Plus it actually does the job really well so there are not really much fumes that could combust. Back when I was using a box fan it was more dangerous because it doesn't remove fumes very well and my compressor makes a ton of sparks at the brushes when it kicks on. All and all I am not the least bit worried. We all saw how hard it was to make a room full of combustable fumes explode on mythbusters.

I'm planning on using a similar method when it comes time to paint mine. But I do want to share an experience with the dangers of this type. I had a brand new rattle can sitting on a ledge at the top of my basement steps. A friend was going in the basement with an arm load of boxes, he kicked the rattle can and it tumbled down the stairs. At the bottom it hit something that pierced the can and the paint started going everywhere. For what ever reason, he let the can continue to spray until it was empty. The basement was about 14ft by 25ft with really no ventilation. When the fumes hit the pilot light of the gas hot water tank he found himself to be in a fireball up to his waist! It was out as quick as it started and there was no real damage, other then it scared the s#!% out of him. He/we got lucky.

Eric

Its a tough issue, because you do want something in place to draw the fumes out. Probably once they hit the fan itself they are less concentrated anyway (especially if they are being mixed with incoming fresh air). I have always put my compressor away from my spraying area, so as to prevent any problems from sparks it may produce. That may also not be necessary?
I am going to try the box fan method when I paint next summer and see how it goes. I may use two or three together as jimM suggested. I'm sure it will be okay.
Thanks for the replies.
Mike

I agree with Satatic, a furnace blower assembly is much better than box fans. Mine has an open motor, but you could find a totally enclosed motor for them. The reason a furnace blower works better is not only because it moves so much air, but its designed to operate with static resistance, which you need since the exhaust air needs to be filtered before ya just blow it outdoors. Box fans are designed to simply blow free-flowing unrestricted air and cant compensate for any resistance, such as filters etc. But if you notice the next time you change the filter in your home, if ya run the fan without a filter, it doesnt move nearly as much air as when its restricted with a filter. The more restricted it is, the faster it runs and the more air it will move, up to a certain point of course.

P.S. Like Satatic, I havent blown up either :D