Portable exhaust fan for spraying waterborne inside of a home

I have project coming up to refinish a friends cabinets taking them from golden oak to painted white. I plan to remove the doors and drawer fronts and bring them to my shop to spray. I will however be spraying likely water based lacquer (Kem Aqua from SW) inside of their residence on the cabs and although no one is occupying the home yet I still want some kind of exhaust fan to pull the fumes and hopefully most of the overspray out. I will be using an airless sprayer. I will also have a zip wall setup with lots of careful masking. I will probably do the occasional refinish job from time to time so I would like to get an exhaust system. Nothing too expensive or major. But I don’t mind spending a little bit up front if it gets me something fairly good and fits my purposes. Don’t want to go over $500-$600.

What do you guys recommend?

Water bourne products do not require any kind of special fan. They are also all low VOC so "fumes" are not a big issue. Particulates, however, are what you need to contend with since the spraying process puts a lot of fines in the air from dry finish droplets that get suspended in that air. Cover everything and close off the room with the cabinets from the rest of the home to prevent the particulates from heading to other rooms (not damaging but a mess to clean up) and use some decent fans to send air to the outside. When you block off, set things up so you can still get cross ventilation...you need air to enter the space you're exhausting air from from the opposite side where you're sending that air outside.

I suggest you test the product you intend to use with the airless sprayer before you proceed. I had a lot of problem getting Kem Aqua to lay down even with a great mid-range gun the one time I sprayed it and haven't purchased it since.

A contributor who doesn't hang out here much these days, but is very knowledgeable, reported that Ken Aqua Plus sprayed really well for him through an AAA. Obviously test, but I bet you'll be fine with it. Like Jim, I hated the stuff in my air assisted HVLP set up until I added about 3% of GF's extender to it; then it laid down beautifully, so that could be an option if you find it's gritty or you have orange peel.

As for exhaust, yes, you want enough to keep the overspray from landing on what you just sprayed, but you will have mostly vertical surfaces so it shouldn't be a big problem. I used to use a cheap box fan in my spray booth and it worked fine. If they get slagged up just buy another for $15 - 20.

John

If you want a more significant fan setup you can try making a fan/door that you can open to get in and out rather than trapsing thru the house to another door. This will let you minimize the containment size (and painty footprints). The fan should exhaust air which will be sucked in thru windows. You can cut holes in your containment for flow. The fan can be mounted in a door sized piece of plywood propped against the house.