Hot Rod Forum banner

Spray Booth Fan Setup

9738 Views 9 Replies 9 Participants Last post by  GMW
I am intersted in making my own spray booth and have seen alot of examples on this website but I am curious about everyone's fan set up.

I know there needs to be a positive pressure enviroment for dust control and I understand the filters in front of the fans blowing in to cut down on dust.....but isn't the fan blowing out, even with a filter, still allowing paint fumes access to the fan motor which on most box fans is not intrinsically safe??
1 - 10 of 10 Posts
Your right filters take out particles not fumes.
Only safe and legal way is an explosion proof fan.
Granger has all kinds of them,
The one I got about 4 years ago was around $500 was not the cheapest or most expensive but the right size for my SQ FT.
barry is right. the fan will always come in contact with the fumes so your supposed to have an explosion proof motor on the fan. the motor on mine isn't explosion proof but its a duct fan and the motor sits on the outside of the fan unit so its not in the airstream. the fan is connected to the motor with a couple belts. if your not looking to get quite that in depth with your project and your just using a box fan then yes you are taking a chance but to be honest with you , i spray in the winter with one of those forced air jet heaters in the booth. been doing it for the past few years and never had a problem.
Anybody know if a Dayton exhaust fan with a "Totally Enclosed Motor" is an explosion proof motor? Also does it matter for a paint booth whether the exhaust fan is located higher than the intake fan?

Bring lots of cash when you go looking for a TEFC motor (totally enclosed fan cooled). The box fans are usually induction motors and would not be a source of ignition like a brush motor would. The on-off switch is another matter all together however.

Here's a stupid question: What happens to your heat when you have a ventilation fan on the whole time you paint? I would like to have a booth with wood (dry) heat, (NOT having the stove directly in the booth, of course) but I wonder if the heat going in would keep up with the heat going out? If not, logic would seem to dictate that the temperature would fluctuate while painting. How about some type of circulating system, you know, something that draws the air/fumes out , then pushes it through a series of filters and puts the same air right back into the booth. Would this work :confused: , I don't know, I'm new to paint booths.
no circulating the air through filters wont work. you need to get the bad air out and fresh air in. in the wintertime heat is always a big factor. my booth moves around 10,000 cfm of air and will suck the warm air out of the building in about 2 minutes. i have seen booth heaters before that heat the incomming air and most are some where around 900,000 btus. just imagine the gas bill for that. i personally use a 200,000btu forced air heater in the booth with me and it keeps it workable in there when its real cold out. the fan on my booth is a dayton 24" duct fan and the motor sits on the outside of it and turns the blades with belts. this is really the best way because it keeps the motor out of the airstream. you shouldn't need an intake fan and a exhaust. just a fan on the intake will work for a pos pressure setup or one on the exhaust for a neg pressure booth. totally enclosed or tefc motors aren't explosion proof motors. if the fan is on the exhaust side and the motor is in the airstream then it must be rated as explosion proof and they are big bucks compared to a tefc.
See less See more
How serious of a booth you talking about??

If it's like most of us hobbist,you are talking about visquene or a sectioned area of your shop.

Building a high (above the floor) filtered intake using regular furnace filters,Poly or Pleated, Not the fiberglass type, with as many filters as space will allow should keep the incoming air clean.

I have 8-20x25, 2 high,4 wide. Opposite the booth from the ex. fan.
Door placement is important as well due to your in & out. You want it in an area where your airflow will pull to the ex. fan direct instead of ACROSS your work as you will allow trash to enter.

My ex. fan is an old belt drive attic fan 24X24 mounted outside the shop 24" above the floor in a sheetmetal box with a louver outlet. The motor is external to the box.

I use filters on the ex. fan intake but they get clogged so fast with material it's a pia to keep air flowing.

As for heat, Thats an expensive one.:eek:
Use whatever but just keep the "fire" out of the booth/prep area.
When doing small jobs, I shut the fan off as soon as the fog clears,then use a couple of the dual lamp 500w shop lights for heat/curing.
I just wait till warm weather for a whole car as I do this for "fun" and not a business,well, not a living anyway.

Wear a "sock" with the paint suit IF you have hair. It's amazing how much trash comes from your head.
I set off a couple of bug bombs if it's been awhile between jobs a day before painting as well as a bug zapper running at all times. Keeps the critter factor to a minimum.
Nothing like a spider crawling across your hood after the last coat of clear.:mad:
See less See more
I use an old (dry) 3000cfm swamp cooler blowing out with 2" thick commercial fiberglass paint booth filter material wrapped around it and the photo shows the other, air inlet side of my booth with inlets cut on the sides and in the garage door. Again commercial paint booth filters are used on the inlet but these are 1" thick sticky wax impregnated pads the consistency of Scotch-Brite pads.


See less See more
You want a "spark proof" fan, not explosion proof. And you want the motor outside of the air stream. If its not, then you want an "explosion proof" motor. Even if your motor is outside of the air stream, if its within so many feet of a booth opening it will need to be "explosion proof" as well, if you care about meeting OSHA requirements. This is called a class I, division II area. Your lights, if in the booth, should be explosion proof to, but most hobbiests don't remember this.

The most efficient booth is a down draft. usually requires pits and is expensive. If you can only afford one fan then put it on the exhaust side and draw air in through filters.
1 - 10 of 10 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.