When building your own spray booth, how do you add working fans?

Coincidentally, I'm almost done building my own spray booth, but mine is designed for air flow from front to back (not downflow).  I used two "muffin" fans designed for equipment cabinet cooling, specifically the AC Infinity axial S1238D set.  These are speed controlled and each provides up to 110CFM at 47dB, but more specifically, they offer a relatively high static pressure that maintains that flow even with a filter in front of them.  I mounted the fans on top of the back of the booth, and do not use any ducting; I'm going to be spraying acylics, and plan on any solvent use in the garage if needed.  (If I change my mind, the fans were purchased with enough static pressure that I should be able to add duct without much loss of air flow.)

I'm using a 14"x24" 3M HVAC filter as the back of my booth and while I don't have the means to measure it, the air flow rate at even medium speed is enough to easily hold a store receipt firm against the filter.

Hope this helps!

d

As a fellow Canadian I would take your plans to a tin smith or HVAC installer and have him build the base for you as you want it. If you have your fan(s) already then take them with you and he can build tho spacificly fit them.

Last time I had a custom sheet metal work don (abour that size but not for a spray booth) I thin it cost me 40 or 50 bucks.Personaly I would start a build like that at the bottom with the duct box, fans and filter and work my way up to the booth on top.

Just a thought.

Bill

My  home made spray booth is  30"w, 15"d, 20"h

The base is made of precut MDF boards. The bottom of the base is 1/4" hardboard. The 1"x2" cleats hold the filter and the removeable spray booth. The exhaust blower is from Granger. The electric motor is located outside of the fan so that the paint won't gum up the motor.

The booth is a plastic storage container that I purchased at IKIA. I turned the container on its side and cut an opening in the side (now the bottom). I used 1x4 MDF boards to reinforce the opening. The boards slip inside  the base and sit on the cleats that are inside the base. A course screen was screwed to the boards to support the model parts while they are being sprayed.

Here is the finished spray booth. A furnace filter is installed between the booth and the base. The blower exhausts via a flexable duct to outside the house. I've used it for years. Works great.

GJP_S2A3

It allows you to spray without needing to use duckwork if you want to, as the fans underneath to collect the paint spray with filters, as there is an on/off switch for the fans.

I would be leary of this claim.

I bought a similar booth (though smaller) from Paasche with rear vent and built in filters. IMO, it is fine if you are spraying acrylics from airbrushes. I quickly found out that the filtering system is highly inadequate for lacquers and I'd not trust any solvent-based paint.

You can only do so much with filter material, and once they start loading up, it goes fast.

I was hoping to avoid ducting outside, but recently added ductwork and I can hardly express how pleased I am.

I installed this inline exhaust fan for 6" dia ductwork.

Booth is connected to enough 6" flexible duct to reach the ceiling, then converts to 6" dia rigid. It is a 35' run, and I'm telling you, I never thought it was going to work.

Here is the Solar & Palau fan in my installation:

It is whisper quiet (the booth fan is much noisier) and is rated at 293 cfm. The guys at the HVAC supply house said it could be mounted anywhere along the 35' run. The Solar & Palau motor is advertised as explosion proof. Ironically, the booth mounted fan is not.

I like having both fans, but usually run only the inline when spraying acrylics. If spraying lacquers or solvent based, or cleaning a/b with lacquers (I do that inside the booth too), I flip on the booth fan.

I don't wear a respirator anymore, the exhaust system is that good.

Good luck with your booth. I fussed and procrastinated over mine for 7 yrs. Wish I hadn't.

I even did a test spray with some Testor's rattle can ClearCoat with nary a whiff.

Edit: I have realized since posting that this is a bit beyond the scope of your question, but I hope you might find it helpful anyway. I had meant to say that should you decide to vent your new booth, with a proper inline fan, you really wouldn't need a booth-mounted fan at all.

I use a single 110 cfi muffin fan and it works fine.  I would stay with at least 100 cfm for a good working both.  I use a 16 x 20 furnace filter for a filter,  They are pretty cheap yet do not create much of a pressure drop.  I have never found the need for a speed adjustment on the fan.

Greg

 

 

GJP_S2A3

It allows you to spray without needing to use duckwork if you want to, as the fans underneath to collect the paint spray with filters, as there is an on/off switch for the fans.

 

 

I would be leary of this claim.

I bought a similar booth (though smaller) from Paasche with rear vent and built in filters. IMO, it is fine if you are spraying acrylics from airbrushes. I quickly found out that the filtering system is highly inadequate for lacquers and I'd not trust any solvent-based paint.

I agree 100% with Greg regarding laccquer and solvent paints. Those types of paint need to be exhausted to the outside. Based upon my experience, filters such as furnace filters, will not capture paint odors.

John