Planers put out fluffy chips, not sawdust so this might be OK for that use only.
I saw a small drum style filter advertised last week by Rockler, the kind with the folded paper filter enclosed in a metalic mesh-walled drum. His container with a drum filter on top might make a decent small shop unit, but you'd probably have to put the intake into the side, or even build a circular unit to go between the collection drum and the filter to create a cyclonic air flow. Air would enter, circle, the chips and larger particles would fall down, the finest dust would go to the filter. You clean drum filters by occasionally blowing compressed air through the outside to blow the sawdust out.
The question posed was about how dangerous fine sawdust is. There are two dangers, first, some woods produce sawdust that has harmful, even carcinogenic, chemical qualities. Second is that though the lungs can clear some larger particles, the finest sawdust stays in forever, reducing oxygen/CO2 exchange and lung capacity, and producing lots of phlem (wet coughing). If you have a heart condition, the second problem can trigger heart attacks, dependence on supplemental oxygen , and constant fatigue and breathlessness. Even with the best dust collection, wearing a good mask should be standard procedure in any shop.
According to a detailed article I read on dust collection, but can't seem to locate again, home shops have far higher fine suspended dust concentrations than commercial shops. In fact, the article suggest that if OSHA inspected most of our shops, they'd shut us down. I keep simple passive dust masks handy and put one on almost every time I go into the shop for more than a few minutes.
The biggest dust problem in my shop has been that it is so full of stuff that it is hard to get the collector hose into all the corners. I've been putting doors on all cabinets to reduce infiltration, but its the dust in every crevice that is really problematic. I recently purchased a couple of HF dust collection carts (2hp), and put a canister filter on top of the one in the shop, which has reduced random dust significantly, but it is still everywhere. I'm thinking of adding an overhead filter box to clean up the airborne sawdust.
If I seem obsessive, it's because I'm a throat cancer survivor and don't want a repeat bout with that disease.
The more I do, the less I accomplish.
Last edited by DesertRatTom; 09-08-2016 at 10:18 AM.