Whats a basic CFM to have for a paint booth

[Polaco]

Hello, not sure if this is the right area to post this but i just had a question that i hope someone could shed some light on.

im thinking of building a booth and work stand for my hobby room. been wanting to do this for awhile now. it would be nice to have my painting station in the same room as my work station. and be able to paint at any given time.

 after doing some reseach, i seen people use alot of different size motors and stlyes. seems squirral gage motors are the safest way to go. little spendy though.

 i couldnt find a standard rule of thumb when trying to pick a good CFM to have for a booth at a size 36Lx24Wx24.5H. i havent built it yet but thats the size i was thinking of doing.

  im planning on using both airbrush and rattle can in the booth. but, im also very new with airbrushing. dont know about the differences between the two as far as over spray. i asume rat can would be more.

there must be a "rule of thumb" figure for a give square inch too come up with the right amount of air flow draw. hate to buy the wrong size CFM motor that either sucked all paint up before it hit the target, or not suck enough and have my house smell like a DuPont factory. 

it did seem that the low end was around 100CFMs and the highs around 250CFMs. so maybe 150-175CFMs would be good? any insite on this would be great. thanks for any replies.

[Roadrunner]

Your booth will be 12.25 cu ft, so a 125 CFM blower, will evacuate the entire contents of the booth a little over 10 times every minute, and I'd think that would be more than adequate. My own booth, at 18 cu ft, and with two blowers running in tandem, drawing a combined 424 CFM at a guesstimated 0.300-in SP (static pressure), will evacuate all air volume of paint booth 23.55 times per minute.

[Miatatom]

I built a booth almost 3 years ago and although it's gone through a few modifications, it's still working fine. My comments are on the second page of this thread:

I'd go for something in the 150 cfm area if I had it to do over. If you're not slinging paint like crazy, it's possible to do a good job of evacuating the booth with a 100 cfm blower. It will fog up a little, especially when shooting acrylics onto lots of small parts. I build a lot of F1, Indy cars and sports cars with lots of suspension pieces. My booth manages a little over 8 complete air changes each minute. 

Edited March 16, 2016 by Miatatom

[Aaronw]

The rule of thumb is based on the size of the opening (height x width), depth of the booth is for the most part unimportant. It is recommended that the cfm / square feet of opening = 100, a down draft should equal 50. So assuming an 18" tall x 2 feet wide opening (3 square feet) a cross draft booth should use a fan of at least 300CFM, a down draft 150cfm.

 

This is a good article on building your own booth that gets into a lot of the theory so you can make good decisions. I used it to build my booth and have been quite happy with it.

 

http://modelpaint.tripod.com/booth2.htm

[Polaco]

thanks guys for the replies. 

aaronw, funny was just reading that link before i checked back here. lots of good info.

if i can swing it, think ill be getting a dayton 1TDR3 gage fan w/ 273 cdm and mount it cross draft. still booth lining up in the air. thought of maybe putting two metal strips of steal on each sides so i could use magnets to attach paper.