I need two cylinders 6" to 12" long, 2" diameter, knurled on their
surfaces the entire length of the surface. I need them to have an end
cap, or FB across the ends, with a true center hole 3/8" dia. This is
for dropping pecans through to crack, and they would both be rotating in
different directions, I haven't decided how to do that yet. I need for
the two cylinders to be able to be separated an equal distance with one
adjustment screw to allow for different diameter pecans.

I think that I may only have to have a drive source on one cylinder, and
the other fixed. I have a gear reduction drive motor that would provide
the rotation for the one cylinder, so basically, it would be for just
the two cylinders unless you got some spare parts that you think would
work well, and not cost an arm and a leg, nor take an inordinate amount
of time. The main thing would be making the throat adjustable, and
maintaining the meshing of the driven gears if I use two gears. If I
use one, it would simplify things greatly.

Anyone up to a small project?

Steve