So, I built a spray booth for airbrushing and spraypainting minis in a controlled environment. Of course, I didn't think to take any in-progress photos, but here are shots of the completed booth.
The cabinet is made from foamcore, and the ventilator is a cheap bathroom exhaust fan. Light comes from three small flourescent under-cabinet lights. The black strips around the fan cover are velcro; they hold a sheet of charcoal filter material in place.
Here is a shot of the back of the cabinet. A piece of 3" dryer duct attached to the fan housing directs exhaust out the window if I'm spraying something with fumes. Yes, that is duct tape holding the cabinet together. The tape on the fan housing isn't holding it in place; it's just sealing the gaps around the opening. For once I'm using duct tape for its intended purpose. :D
The shape of the cabinet was driven by three things: the size of the air filter (14" x 24"), the size of the exhaust fan (and it's cover), and the space between them. I cut a piece of foamcore to the width of the filter sheet, then cut a hole near the bottom center of the sheet to fit the fan housing. The foamcore was scored above the fan hole to allow it to bend. On another sheet, I marked out the shape of the cabinet sides, based on the three important dimensions above.
Another sheet of foamcore, cut to the width of the filter, is the base of the cabinet. I taped the cut-out sides to the base. I taped the back of the sheet to the sides, then cut another slightly wider piece for the top and taped it in place.
The fan was wired to an extension cord. I'm using a power strip to switch it on and off at the moment; if needed, I'll wire it into a switchbox. After wiring, I fit the fan into place. Scraps of foamcore were stacked and taped into place below it to match the height of the hole. Last, other scraps were taped into place inside the cabinet as stops for the filter.
It seems to work well. We'll see how it performs once I start putting it to use. One important note: this fan's motor in the airflow. Using this setup with flammable solvents can be dangerous. If you use the same sort of fan for a similar project, be very careful with cans of spray paint.