On Thu, 26 Jul 2007 08:36:02 -0700, Jeff wrote:
On Jul 26, 11:20 am, wrote:

Move the jig a hair closer to the bit.

You mean move the pin a couple thousands of an inch closer to the
bit? I'm not going to be able to move the pin with that type of
precision,

Yes you can. Here's a jig that illustrates a rather complex form of
the adjuster

http://www.woodcentral.com/cgi-bin/readarticle.pl?
dir=jigs&file=articles_436.shtml

although it doesn't explain it.

If you use a screw with a known pitch, you can calculate the exact
amount of movement ("lead") each turn or portion will produce. The
common example is a 10-32 scew--each turn produces 1/32"(0.3125")
movement. So an eighth of a turn is 1/256" (0.0039"), a very fine
adjustment indeed. Mark the screw head and use a paper marking circle
with 10 degree increments to keep track of even more precise fractions
of turns. 11.52 degrees equals 0.001" although that won't divide a
circle evenly.

My own jig is simpler, I used oak for the moving face and an insert
nut in a tailpiece glued onto face of the backboard. When set, I just
clamp them together.


--
Steve Hall [ digitect dancingpaper com ]