Thinking of building a spray booth... In my basement

[smier]

I have no garage, but I have a huge coal bin approx 8' x 8' that has two windows I could use for ventilation in my heated basement. It's in the corner so 2 of the walls are concrete, and the other 2 are 2x4 framing. I need to install a door and more lighting. The windows are hinged and swing up so they could drop the coal in from the outside. I can seal off this room from the rest of my house, but I have a natural gas water heater with a pilot light and my oil fired furnace about 20 feet away at the opposite end of the basement. I don't want to blow myself up!!! Am I completely insane? How can I make this work?
I already have the equipment, but no place to use it and it all just sits in my basement since I lost my 3 car garage. I sold all my car projects when we moved, I only kept the Blazer and my old dirtbike, which, I'm doing a full restoration on in my basement this winter, hahaha!!! I also hope to be able to use a small blasting cabinet and safely paint small parts from the blazer, bikes, my sons RC cars etc...

 

[ryoken]

I'll put up a post tonight, and get back to ya on the salad bowl too...

 

[smier]

I was looking at the old coal bin last night, because of how both windows swing into the room I can easily install removable air filters (I work for a heating and air company) into the window frames. Would simple window fans work for providing ventilation? Do I need to provide fresh air ventilation in via a fan, or just having fan(s) sucking the bad stuff out? I guess I should make it simpler:
Options:
1. Both windows open with filters installed, one fan exhausting thru one window, one fan drawing in fresh air.
2. Both windows open with filters installed, one fan exhausting and just allowing fresh air to be drawn into the room naturally.
3. Both windows open with filters installed, fans in BOTH windows exhausting the fumes and overspray.

Covering the walls, I was thinking of buying that white plastic paneling they use in RV's for ceilings to cover the framing of the two interior walls and ceiling, and installing a simple homebuilt door. Should I put a ventilation opening to allow air in thru the door? I could also incorporate a filter into this door. Realistically the largest things I would paint in here are probably motorcycle gas tanks, frames, and fenders etc., and I won't be using it very often.
Safety: Ventilation - How much is enough?
I don't want to kill my self from fumes, nor do I want to cause an explosion. I can control the oil burner by simply turning it off if needed, but the water heater has a pilot light that burns constantly and has proven to be a challenge to relight in the past... How close is too close, and how long do paints typically give off flammable fumes?

 

[76zimmer]

If possible I would put an exhaust fan in the window with a filter covering it and seal it to the window frame. this will keep any bugs out.
Then make an intake filter for filtered fresh air from your basement, this will allow reasonably room temp filtered air to be supplied to your booth. Try to get a crossflow if you can. I would also put up plastic on the walls/ceiling to help keep debris infiltration out of your booth.

 

[terky]

Try to get an explosion proof exhaust fan. A good way to achieve this is to have a belt driven fan with the motor out of the airflow.

Same goes with the light switches, do not put them in the paint booth.

I have built 1 commercial paint booth. Not a ton of experience but you really don't want it to go boom.

 

[Fordum]

Am I completely insane?

Probably, but lets stick to the paint booth idea.

since I lost my 3 car garage

Dang, I lose my keys from time to time.................

Anyway, the way I understand it, the area you are wanting to make into a booth is partially separate from the rest of the basement.
The only way I would do this is to have that section totally separated from the rest of the room.
To start off, seal it up so that no air passes between it and the rest of the basement.
Then, you could have a fan in one window and a filter in the other.

The fan would have to be pulling air from the room. You want negative pressure in that room so any air leaks will be coming in from the basement and nothing will be going out except through the windows.

Of course, this is going to get cold during the winter. You can help this by putting a window in the wall opening out into the heated basement with a filter.

When you use it, you will need to partially or completely close the intake window to the outside so as to maintain the negative pressure.

Of course, this will run up your heating bill when you are using the booth.

Also, to be safe, never mind code, all lights in the booth need to be explosion proof.
The fan motor is supposed to be explosion proof also. But, if you make sure that the motor is well out of the air stream, you might be OK.
In other words, no fans with the blades mounted on the motor.
Remote belt drive only.

We had a paint booth at my shop for years. The lights were regular 150 watt floodlights, but they were inside big glass domes with a gasket, and the wiring ran through some heavy sealed conduit.

The fan was a belt drive, but the motor was too close to the axle and so was in the airstream.
It had been that way for many years before I got there, so I never noticed. One day an inspector came around, and casually mentioned that we needed to clean the paint off that explosion proof motor.
After he left, I went outside to do that and discovered that it was a standard open frame motor!
There was so much paint built up on it that it looked sealed.

We got an actual EP motor at a local motor shop and bought the necessary EP conduit to install it.
Not cheap!!

I would also consider putting thick sheetrock on all the walls and ceiling. Relatively easy to get paint build up off of, and under most conditions will not support a fire.
Concrete block will hold paint like mad.

 

[smier]

Lots to think about, but definately doable! I'm not that worried about paint buildup because this won't be used much? Lighting is easily solved, I can get conduit etc. Thru work at wholesale cost. EP fan setup will be the sticking point... Might have to get creative on this one.

I liked the idea of using the window to control air pressure, I hadn't thought of that. I can easily just use a small chain and hook to open or close the window. I was thinking of using the heavier duty air filters like the allergen ones to help control the fresh air in, but also to catch as much overspray as possible on the exhaust side? I'm guessing I'll need a heck of a fan to get negative pressure?

I think it's time for a bit of an experiment. I think I'll build a door, and get some really good air filters. Seal all the cracks and crevices in the room with spray foam insulation, and the experiment by attaching a box fan outside of the window. I actually have draft guages for working on heating systems, so I'll be able to measure positive or negative pressure, as well as see what works and what doesn't! Then, I would only have to come up with a way to overcome the fact that my windows are high on the basement wall at ceiling level, so I would be creating an upward draft scenario... Hmmm, I have access to make some hard ductwork... This is my basement shop, it's not a dump, but I'm not entertaining guests down there.

I can get my hands on some old belt driven drum fans used in forced hot air units, but they would probably pull all the heat out of my entire house in a matter of minutes.

And to think, I was originally afraid to start this thread because I myself thought it was a pretty crazy idea.... The best part is, I already have or have access to a lot of the stuff needed!

 

[Fordum]

The only problem with the squirrel cage drum fans, is that they draw in from the sides. This makes it hard to control where the suction is coming from.
The output is easy, but the input is the problem.
The best way would be to mount it inside and seal the output to the wall going out. But that eliminates the advantage of having the motor away from the fumes.

As for the amount of air, just change pulleys. Run the fan at whatever speed you want.
I have built plenty of fans out of those old units, and sometimes I have to slow them down some to keep from overloading the motor.
If they are used in a duct system, it can starve them for air enough so that if you just set them in open air, they will suck in too much and overload the motor if you use the original drive.

As for creating negative pressure, you don't have to have your ears pop when you turn on the fans. Just a few inches of water is enough to ensure that no fumes gets out into the rest of the room.

Of course, if you are a bio-hazard containment lab working on mutated Ebola, then you want some more differential.

And, as for the conduit, I doubt that you have any at work that you can use. Explosion Proof conduit is a whole nother breed of cat.

You might be able to eliminate the need for it though. You could cut holes in the walls, seal them with heavy Plexiglas or Lexan and mount the lights outside shining through the holes.
As long as fumes cannot get to the bulbs, then a bursting bulb cannot ignite them.
Don't let the bulbs get too close and melt the covers if you use heavy incandescents.