Building spray booth - a few questions:

[bradnailer]

I've been reading the old threads and thought I had some answers but then I see a couple answers contrary to the others and I'm back to square 1. Here goes:

1. Do the good furnace filters (3M ones) filter well enough to not need an exhaust to the outside? (ie like my stovetop filter that doesn't vent to the outside) I don't have an easy way to vent to the outside unfortunately (can't put a big hole in the wall to vent out of...) I was thinking of using twin furnace filters....



2. I have the Caswell $200 collector, can I use it as the collector for my PC booth AND then move it to my blaster as needed or will I get contamination in my spray booth somehow?

3. If I can make all my walls, ceiling & floor metal in my spray booth, will that be the best way to go? (can I use galvanized metal?). Or just bend a piece to cover the 2 walls and ceiling?

4. How do I ground my metal walls in my booth? Do I put a screw in it and then run a wire from it to the ground in the power receptacle that my PC gun is plugged into? If not, how else do I ground it - I totally don't understand how to ground it.

My booth is 36"x36"x40".

Thx for any help!!

[cdaeme]

You have a PM reply Brad.

Jason

[FigureLLC]

1) no. the 3m filters, while they work pretty good to start, clog quickly and then the powder starts to pull through. my first booth filtration system was an mdf box (4'Wx3'Hx2'D) with a 1200cfm squirrel cage blower mounted in it exhausting through the 2' side, and the 4' side had two of the 25"x20" high efficiency filters. it worked ok to begin, but like i said, as soon as the filters load up, the powder's going through - and through the blower (still never killed it or blew up). there also was not a lot of air moving through the filters.

LESSONS LEARNED: A) furnace filters are not good enough to exhaust inside. B) squirrel cage blowers lose efficiency VERY fast when the flow is restricted. radial blade blowers - also known as high pressure blowers - are the ticket.

2) it's probably fine for both? we just started using cyclone separators (one for the shop vac and one for a 55gal drum) and they're amazing. no filters to clog or replace, no loss of flow, no moving parts (besides the blower that you'd have anyway). do a search for "cyclone separator" on here and you'll find a link i posted to the ones we bought on ebay. they're VERY reasonably priced.

3&4) yeah, galvanized steel will work fine. my first booth was a frame made out of pvc (sturdied up by criss-crossing steel cables), the floor was mdf, and the walls and ceiling were plastic 6mil disposible painters tarp duct taped to the frame. "HOW can you ground THAT?" turns out it doesn't really matter. whatever your parts hang from need to be grounded. if you look at one of the lower end nordson powder booths (the window style, not walk-in), the three walls and ceiling shell is polyethylene or something. the metal bar where you hang your parts is grounded. but yeah, use screws or aligator clips or whatever you want. just take a multimeter to everything to verify that it's a complete circuit to the earth ground (earth ground can be a piece of conduit since outlets are grounded to the j-box which is connected to the conduit. again, just use a multimeter to verify continuity.

if any of that is unclear, lemme know!

[Banditperformance]

Len, how was the poly fro cleanup/color changes? I need to redo the walls in my booth. I got fed up wioth drywall chips and leftover powder contaminating after a color change. had a little hissy fit in there today LOL, not I REALLY need to do something about it. Was thinking Poly, but how is it for cleanup with the staticness of it??

[FigureLLC]

being smooth it was pretty easy. i can't say we every ran into problems with cross contamination, and we'd do color changes without cleaning the walls. it really doesn't stick very much. broom or dry cloth it. it's much much easier to clean than the mdf parts of the booth. i'd say it's worth a try since it's cheap.