AWilson

I'm using 3 -20 x 20 inch box fans as my fresh air source. They are mounted on the fresh air side. 4 inches in front of them I have 3 - 20 x 25 inch furnace filters. I have always heard to buy good filters so I bought these because they are rated as FPR-8. But to me they are very restrictive. I don't think the flow through them is even a third of what the fans can do without any filters.

What FPR rating filters have you guys used and still gotten great results?

lushdrunk

My father in law is a HVAC guy I will ask him what he thinks because I know nothing about the ratings or types of furnace filters.

But sounds like you have a nice homemade set up, I did basically the same thing except I used two large 230v, (sealed motor) furnace fans. (hamster cages as my father in law calls them). For fresh air and exhaust for a "cross-flow" type of booth,

Ive had some problem finding a good usable filter (cheep) that would allow the right amount of air, without coming apart or allowing paint to go right through them. The cotton filters can cause little parts of cotton to come off and fly through the air. And they allow paint to go through them.

I use the thin cheep paper filters you buy at any store. I get mine at wal-mart or Lowe's
they are 20x25 and cost $7 for a two pack. They have a white paper front and cardboard edges. They are the cheapest paper filter wal-mart/Lowe's sells.

Ive only been using them for about 6 months now, But I have yet to have any issues with them like I did with the cotton filters. But their no where near as good as the cardboard paint booth filters sold by ITW.
I switched to the furnace filters after I let my father-in-law talk me in to it. Before I was using the cardboard maze type filters that offer very little restriction and do an amazing job at catching paint. But they had to be ordered and only came in a box of 10. At a cost of $170 per box vs $7 for two furnace filters that do the same thing and can be picked up almost anywhere locally.

What type of box fans are you using? I will ask my father-in-law what would flow the best for you... He should know.

DUB

A word to the wise:
A new ruling from the EPA is going to take effect in early January 2011.

I went to the meeting and got all the paperwork so I can be compliant when it come to "life".

Home paint booths when painting more than TWO cars a year will fall into HAVING to be compliant.

Everybody is calling it the 6H rule.

Specific spray guns ( no less than 65% transfer rate) will be required and also using 98% efficient exhaust paint arrestors will also be mandatory.

You MAY have to record all paints that contain the "heavy metals" listed in this ruling.

Not really a big deal...but just one more thing to add to my list of things to do to run a shop.

SO enjoy it while you can...because I am sure before you know it...you will have to have a license to buy paint before it is all said and done.

"DUB"

AWilson

I'm lucky if I paint 2 cars in 5 to 10 years.