Morning Doug,
I have had allot of experience with cyclone technology over the last 35 years as I work in a plant that relies on them for production. And trust me I have been on the end of quite a few when they block up as well.. Bear in mind that the cyclones I am used to are capable of holding 200t of product..
Most cyclones can be put in to one category, that is they separate the material from the airflow.. It doesn't matter what make they are that is all they have to do...
This link below is one that Bill Pentz had published in the woodturning magazine, at the time I thought it was a good layout and could be scaled down to suit.
http://webpages.charter.net/pjbolin...eparator - cyclone and thien baffle plans.pdf
The most important thing with a cyclone is to reduce the material speed but maintain the air volume through the cyclone.
To do that, the inlet needs to be made at least 1.5 times the size of the outlet.. And the vortex finder (dip tube) depth should be at least 60% below the top of the material inlet.. But remember.... Anything smaller than PM10 will go through any cyclone and block up the filter, even the famous Mr D can't beat that.. That's why one or two on here have blown theirs up..