I may be mistaken, but I believe that the purpose of the cyclone is to
separate the larger particles, like sawdust and wood scraps..
your DC filter bags are your main filters, usually followed by an air
filtration system..

a good cyclone will separate almost everything out. all but the finest sawdust.
when I clean my filters I get this extremely fine sawdust that will float for a
very long time in the air. but that's all I get. I would get little of that if I
did not work some pretty bad tropicals.
if you need a air cleaner afterwards you have a poor setup. you want to catch
the sawdust before it gets in the air not afterwards.

--
Knight-Toolworks & Custom Planes
Custom made wooden planes at reasonable prices
See http://www.knight-toolworks.com For prices and ordering instructions.