Spraying and air quality and exhaust fan for basement?

[Phil Thien]

I historically haven't done much spraying. Now that I have done a bit, I'm stunned by the spikes on the Dylos meters when spraying even a tiny amount.

If I want to spray in the basement I will have to rig-up some exhaust system. But all my windows are glass block.

I'm thinking of making a frame from some rot-proof material that could hold an exhaust fan, blowing an entire glass-block window out, and installing the frame+exhaust fan in its place.

The problem is, the fan would actually be in a window well, and I have concerns about how to seal it up in the winter and the rain and stuff.

Another method would be to install an exhaust vent where one of the glass block tiles are now, and attach a blower to that. When my kitchen was remodeled, the installers broke-out a single glass block tile and installed a port for the over-the-range vent. So this would be along those lines. The downside with this method is the blower I now have to find a place to install.

Anyone have any sage advice here? Or pics of what you did?

[David Kuzdrall]

This may be considered "ghetto" but I once repurposed my HF dust collector to be used as an exhaust fan for a makeshift spray booth. I just opened a window on the opposite end of the garage for makeup air and cross ventilation and had great results.

the advantage to this in your case is that the outlet can be small...perhaps even a dryer / bathroom exhaust vent with a flapper so you don't have to worry about rain or critters.

[David Kumm]

My concern would be the small outlet. Most finish fans are axial and meant to move a lot of cfm at low pressure and something like 100+ per sq ft. Really small projects can be handled by a small inlet/outlet fan but a 3x5 bank of filters needs a 12" axial. they don't work with an outlet much smaller than their diameter and DC impeller doesn't move much air until you get to the larger sizes. Are you going to spray any solvent based stuff? That requires lots more effort to set up right.

[Peter Quinn]

I put a 15" gable vent fan in a tapered box that blows out a 12X24 basement window, its a hopper (inswing). So I swing the window in, it hooks in the horizontal position, there is a little door in front of the fan I can open to reach in and open the window. I built a 9X11' room with removable panels, simple ladder frames wrapped in 6mil poly, they screw together, jog around joists, hung an old sheet as the filter/door. It works. I spray waterborne only. I've read its nearly impossible in a non production based environment to actually reach a air fuel mix that can ignite spraying solvent based (not read from a crack pot, but an actual engineer ran the numbers and tested it), but thats still a lot of stink to unleash on your home and neighbors. So I don't do it. I never got a dylos meter involved, but I do wear a good respirator. I tried to spray a small piece once before I built this simple booth, in seconds I was standing in a cloud , thats with an HVLP gun spraying low volumes of surface. You have to pull the overspray away from the work, and its best to push it outside.

I envision building a box on a swing arm in the future that 180 degree out of the window, so I can open and close the window easier and clean up occasionally the overspray that makes it past my filter. MSC sells articulating arms to hold fans, I'm thinking I could build one from plywood and dowels for zip.

Here's a few pics.

[John TenEyck]

I have glass block windows in my basement shop. Fortunately, I installed a a vent window in one of the units, and I use it to route a hose outside from my DC fan, just like DK mentioned. It's a 1200 CFM fan using a 5" diameter hose. I have NO overspray or dust problems. The makeup air comes from upstairs and probably down the chimney, too, so I always make sure to turn off the boiler when I spray. I've been using this system for over two years now with no problems with finishing or buildup/corrosion, etc. to the DC internals. I only spray shellac and WB topcoats, never any solvent based ones (besides shellac).

In your case, I would knock out a single block or enough of them to install a vent window like mine. No reason to knock out the whole panel. If you are concerned about makeup air, then install a second vent window in another panel in your shop. Put a disposable filter over that window when you are spraying.

John

IMG_7213.JPG

[Richard Coers]

Will you be spraying solvent or water based? Downside of spraying solvent based is the outgassing after the spraying is over and the finish is curing. It will takes hours, maybe a day with some finishes. Want to keep the fan running that long? Think the wife will mind just a "little" smell? Mine didn't mind at first, but then when she ran a load of clothes in the basement dryer and her clothes smelled like the finish, the happy wore off pretty darned fast.

[Phil Thien]

Great replies so far guys, thanks.

I will NOT be spraying any solvent-based stuff, all water-based.

My thinking at this point is to put one of the drier vents in where one of the glass block tiles are now, and then hook that up to a 1-1/2 HP blower. Makeup air can come from the house and I can turn off the furnace when I do this.

After all, I'm better at starting projects than finishing them, so I don't actually have much call for spraying the finish, LOL.