On 2010-06-14 20:25:16 -0400, "Dr.Deb" said:

Today, I was planing out a couple of ash boards and noticed a bit of
debris coming back out the infeed slot (always a clue the cyclone is
plugged).

This seems -- in my limited experience -- to be characteristic of ash.
The wood doesn't chip, but produces fibrous strands. And if you think
of a hair clog in a drain, that's the same sort of mess. Humidity or
wet wood makes the problem worse.