Dust in my shop is really going to be a problem soon, once I start finishing the fuselage or start construction on the wing. All the balsa dust, sanding of the primer and body filler, etc, it'll really make a mess. While most of it ends up on the floor, plenty still remains airborne or clogs up my furnace filters. To FINALLY start addressing the problem I spent some time wading through YouTube videos for homemade air filtration ideas. Most of them are made by woodworkers with nice big shops, table saws, router tables, etc, none of which I have, so I kept looking at options.
Then I found a very basic filtration device that was simple, cheap, and worth a quick trial. It all starts with a $1.00 filter that probably isn't necessary. The balsa dust or sanding dust is typically too small to get caught in here, but I'm trying it anyway. You can see my hand through the filter. If you plan to use a filter system in an area with a lot of pets this filter would probably keep the hair from making it to the main filter, so use your judgement.
The next filter is the main one that'll pick up most of the dust. It's not expensive, only a few dollars, but it's got a much tighter filter fabric than the pre-filter. From what I've learned, the real expensive filters aren't worth the extra cost as they get clogged fairly quickly with this type of application. It's better to buy a bunch of cheap ones and replace them regularly.
Note that on the pleated filters there is a specific installation direction, so be sure to install it so air flows properly. The pre-filter doesn't matter.
Here we go, filters are stacked and I ran a couple pieces of painters tape to hold them together
It's fairly half-assed, but again this was just a test to see if it was going to work. The filters were taped to an old box fan. These are just barely big enough to cover the face of this old box fan. If it works, the setup is very portable (note the handle!) and cheap. Many of us have these old fans laying around doing nothing for the past few decades. This one was sitting in my garage unloved for at least a decade. The other one I tested is even older. I have a slight concern that the filter will block airflow to the point where the motor overheats, although if the filter is replaced regularly I don't imagine it'd be an issue. Hopefully. NOTE: I say that after the other older fan died after about 10 minutes on high speed with the filters on. It was an old unit and I knew it was somewhat temperamental, so this may have just given it that final push over the edge...
Here's the result of my test. I set the fan on the floor under my workbench and sanded the spot primer off of one of the elevator halves. I wasn't sanding over the bench, but in my hands so the dust would fall directly down towards the floor. Obviously much of it was pulled into the filter, and about that same amount ended up on the floor. This dust is heavier than balsa dust, and when I tested with balsa most of the dust got sucked into the filter, far less was floating around than usual.
I see some promise with this and will continue testing it for a while. I can envision incorporating it into a sanding booth or into a down-draft table for sanding, although a bigger fan unit would be required. It would require a different type of fan for painting, but again there is promise.
