Michael Wendt on sun 13 jan 08
Some thoughts about jiggering
on a standard potter's wheel:
1. most wheels use shafting that is
too small to be rigid. a 3/4" shaft
is much more flexible than high
quality jiggering requires.
2. the bearings on standard potter's
wheels are too close together.
They are so close together they
care not able to resist high
radial loads adequately, loads
that a jigger arm would cause.
I use 1" shafting and the bearings are
7" apart. On a jigger, 1 1/2" shafting
would be better.
3. The type of pillow block I recommend
in this application is called SealMaster
gold . It uses a collet style shaft clamping
system that centers the shaft accurately
in the bearing.
4. the frames of most potter's wheels
are fairly thin metal (3/16" - 1/4 ").
A jigger machine
requires a substantial bracing system
from the tool post to the bearings on the
bucket head of the unit. Every component
must be very rigid and move with little
or no run out (wobble). Otherwise, chatter
can result as well as inconsistent thickness.
I still think potters would be better served to
learn to make plates faster rather than
resorting to jiggering.
Just my thoughts.
Regards,
Michael Wendt
Wendt Pottery
2729 Clearwater Ave.
Lewiston, Id 83501
U.S.A.
208-746-3724
wendtpot@lewiston.com
http://www.wendtpottery.com
http://UniquePorcelainDesigns.com
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