Dirt cheap and easy shop air cleaner

In order to do a bit of routing and sanding inside without getting lung cancer, I wanted to set up some form of air filtration. I spent a lot of time designing a downdraft sanding table that could double as an air cleaner (plus add tool storage drawers), but cooler head prevailed and I went with the easiest thing that could do anything at all.

This is simply a box fan with a 20" Filtrete filter, hung from the floor joists with three eye screws, eye bolts, and spring snap links. It blows up between the joists by default, or I can release one clip to drop it down if I really want to get the cyclone going.

It runs through a "power saver" outlet, so after a nice afternoon of raising dust, I can hit a button and walk away and the fan will run for 0.5, 3, or 6 hours. In practice I keep it on the three hour setting, turn it on as soon as I start using a power tool, and let the timer run its course after I leave the shop.