Squirrel cage swamp coolers was a term used in the Car Craft article I was referring to, but I wasn't sure what they are?
Would that be like an old furnace blower motor, belt driven, with the motor out of the direct path of the vapors?

I also thought of the fan blowing "into" the area through the furnace filters as a way to keep the vapors from exiting through the fan motors.

But really, it would help me if I knew how a "real" downdraft paint booth works and the set-up.

My intended method was to creating a "drawing in" of the filtered air, but I'm not sure how the fumes will exit if I blow the air in through the outside of the filters. Won't the vapors and overspray just settle wherever if there isn't something pulling the fumes out?

Thanks.