A few months ago we briefly discussed a great tutorial on how to make a 5 gallon fine particle dust separator. The tutorial has since been taken down from the now-defunct ShopNGarage forum, but luckily Goodfellow was able to post it up at the new Garage Gazette forum.
The great thing about this simple design is that it can be adapted for use on sawdust and other types of debris, not just blasting media. Without a layer of water at the bottom, the trap will separate out larger debris before it takes up space in the shop vacuum.
This separator probably won’t function as well for sawdust applications as a cyclone separator, but it should hold its own against other conventional separator designs.
Fine Particle Dust Collection Separator via the Garage Gazette
Photo Credit: Goodfellow
Update: Forum link is dead.