Finishing Area

[Jerry Bittner]

Well I just about got the plans finalized for creating a temporary finishing room in my workshop.

I say temporary because I don't have enough space to make a permanent area. So what I've done is buy some 3/4" electrical steel conduit, three ten foot pieces actually. I put a 90 degree bend in two pieces and bridged that with the ten foot piece so now I have a "U" roughly that I will anchor each end of the "U" to the wall and support the middle of the "U" with a hanging bracket. In effect I've creted a shower curtain and I 'got some tarp from the Ogange Box with eyelets that will serve as the shower curatin hanging from the pipe to ground level. Actually, two 15 foot wide pieces that when not in use will be pulled to the wall end on both sides out of the way of normal work. When I want to screen it off, I just pull out each curtain to the hanging bracket and tht break in the "curtain" serves as the entrance.

It works great and all for an investment of $30 bucks.

Now I'm seeking some advice. I want to vent the area and thought about installing a furnace type filter in fromt of one of my dust collect ports. HOwever, I was concerned that if some of the overspray got past the filter, would it damage the bags. Contacted Grizzly, my make of the DC, and they recommended against it.

Anybody have any idea of what filters would ensure me of no escape of overspray? If that isn't an option, I'll discard the DC idea. Next brainstorm is I thought of buying an "over the range exhaust hood" and vent it through the wall. My question is whether the typical range hood has sufficient power to do a decent job exhausting the area (roughly 10 by 10 by 9 (ceiling height)?

Appreciate all the feedback I can get.

[Todd Burch]

Jerry, not sure what you'll be spraying - whether it is volatile or not. Either way, I also would not suck the fumes/overspray into a dust collector.

Your cheapest solution will probably be to purchases a used furnace fan/squirrel cage, either at a garage sale or from an HVAC repair guy that replaces them. Build an OSB box around it and put some cheapo filters in side cutouts. All the filters do is keep the big overspray particles from gooing up the blades on the fan.

I would suspect that you won't be spraying so much or in such a confined space so as to worry about getting an explosion proof fan. A typical house squirrel cage fan will move anywhere from 1500 CMF to 2000 CFM pretty readily, and in a small space, that exchanges the air pretty quickly. I've used them for years.

The range hood vent fan is too small, unless you will be spraying matchbox-size parts. A 10 X 10 x 9 area is 900 cubic feet. Use that for calculating air exchange rates.

And, the squirrel cages are so cheap ($10?), if it does get gooed up, throw it away and get antoher one. No big deal.

[Jim Becker]

I only spray water bourne finish so I didn't bother with a formal (or informal) finishing area...I just clean up the north end of the shop very well with broom and vac, move any tools from that area, cover anything that cannot be moved with an old sheet and spray. My air cleaner running on "high" serves to pull suspended material from the air and a respirator keeps it out of my lungs while I'm spraying. Keep in mind this is all non-VOC water bourne finish...no NCL lacquers or oil-based products.

[Jerry Bittner]

I should have mentioned that I'll probably be spraying both waaterborne and volatile.

Todd, thanks for the info -- never thought of that route. So the squirrel fan just collects and in your scheme you don't bother venting it to the outside -- right?

That maybe just the ticket I'm looking for.

[Todd Burch]

No Jerry, it absolutely vents to the outside. In with the fresh, out with the particle and fume laiden. The filters simply catch the particles and keep the particle build-up from happening to the fan. The fumes (and VOCs and HAPs) go right through to the atmosphere outside, just like a commercial body shop's fumes.

Now, if you were to invent a "collector" of some sort that would capture the fumes, extract the VOCs and HAPs from the good air to to keep them from being dispersed into the atmosphere, well, Jerry, in several years would be die a very happy triple quadruple multi-ka-zillionaire. $$$$.

[Robert Grady]

Jerry, the best configuration for the fan is to blow into the finishing space through a high efficiency filter. A 2" or 4" thick pleated will give the higher efficiency. This will keep your finishing space at a positive pressure compared to to larger area around it thus keeping particales from entering and landing on your workpiece.

And for a mere quarter million you can have a machine that will extract the VOCs, burn and discharge the cleaned air. It is a Thermal Regenarative Oxidiser. I thought every woodowrker had one:)
Good idea on the portable clean space

[Ken Leshner]

Jerry,
If you are going to be spraying volatile materials you should equip your booth with an explosion proof fan and lights. Also, you should check with your local building department to make sure there are no restrictions on what you're planning to do. Also, I would contact my insurance company to make sure they will cover you in case there is an accident.