On Fri, 20 Dec 2013 22:36:13 -0700, SteveB
wrote:

On 12/20/2013 7:41 PM, Pete C. wrote:

Ignoramus28970 wrote:



I'm not sure about that design. When I moved to TX and found I had pecan
trees I searched around for pecan shelling machinery designs and don't
recall any that cracked across the short dimension, they all worked on
the long dimension. I found the easiest thing for me is a 1T arbor press
where I can just stand the pecan on end and apply a small amount of
force to crack without crushing. The separation once cracked is the real
challenge and from what I found far too complicated to try to replicate
small scale.

Had investigated short travel actuators that could deliver a stout blow
to a nut held so it impacted the ends. Might still go to that. I would
eventually like to come up with something that allows me to get two
halves out, even if it takes some finger time, and it is not all
automatic. The machines for that are around $15k. It needs to shatter
from both ends without compressing enough to contact or damage the meat.
Probably 1/16" to 1/8", something it would be easy to do with an
actuator and some steel stops. Even did some experimentation with
dropping ball bearings, but didn't have the inertia, and the variables
of the different nut ends produced nonrepeatable results.

For right now, some people want the nuts just cracked, and they will
extract the meat. This would be the purpose of this machine. Just
crack them enough for the buyer to do the rest. Some places charge up
to 50 cents a pound to crack pecans. Sounds pretty lucrative to me for
running them between two spinning rollers.

Steve

My great uncle Bill built several that used opposed cylindrical
weights, about 1-1/2" x 4", sliding on rails 1" apart. One weight was
operated by hand to load a pecan, the second weight with limited
travel was struck every few seconds by a third which was drawn back
and released by a little gearmotor and cam. I don't remember the
release mechanism, but it was simple. Force was regulated by the
number of rubber bands on either side of the striker. Pull back the
hand weight, stick in a pecan (there were conical recesses both sides
to hold the pecan), the striker would be released hitting the limited
travel weight, pecan breaks, drop the pecan through to a bucket
underneath, stick in another. It went pretty quick, and they were
perfectly cracked for separation.

If I had any bearing pecan trees, I'd build one.

Pete Keillor