A little while ago this appeared on hackaday:http://hackaday.com/2011/01/05/quiet-dust-extractor-from-scavenged-materials/
Since I'm in the middle of a woodworking project, I thought that I would make an attempt at creating my own cyclonic dust
separator. I first looked at this:http://store.oneida-air.com/dust-deputy-diy.aspx
Which reviews well, and would probably fit my needs (my needs are to stop my shop vac filter from clogging after a few sheets of MDF on the table saw). At $59, it's not overly expensive either. But I thought I could do better. What I came up with is in the picture. Note that This does not catch microscopic particles. I currently vent out the window, but I may add a filter system eventually. It LOOKS like clean air coming out, but those microscopic particles are really bad for your lungs, especially in indoor concentrations. In subsequent posts I'll document the build and results.