For those of you looking for a small shop, low costcyclone solution, go to ebay and search dust separator and look at the first one that comes up. I bought one of these and put it between my cnc router and my Delta 1.5 HP dust collector. It works so well that I'm amazed. I use mostly small end mills on the stuff that I cut and the chips are very small. This separator catches even the smallest of them, with virtually nothing going into the collector bags.
It works so well in fact that I disconnected the hose from the bags and I vent it outside now for less restriction and more suction. I live in the sticks, so that works for me.
Just telling you what worked for me and saved me a pile of money.