On 12/5/2012 8:45 AM, Jim Wilkins wrote:
"Tom Gardner" Mars@Tacks wrote in message

Hire a machinist :-)
Ain't that cheating?

If I had to do this job with what I own I'd use my index to drill a
circle of dowel pin holes and then make a bandsaw jig that located the
blank from each dowel pin and the center hole.

I'd clamp the index and a bench drill press to a long solid surface to
drill the holes, then jack up a length of straight stock on a
hydraulic table to bandsaw table height and guide the center and index
dowel pins along its edge.

I think I could jig up up my surface grinder to support and locate the
center and finish the radial edges with a dish wheel. I would measure
the spacing between all the pin holes and use a spreadsheet to
calculate the offsets to correct for their variations with the Y table
feed. Pin n's proper position is at SumOfAll * n/118 from the starting
pin, which is the one that makes all corrections a positive number.
It's actual position is the sum of the spaces before it. Each space is
the measurement across the pins minus the diameter of one, which the
spreadsheet does for you. I'd double-check SumOfAll with a tape
measure.

If the errors are small the pivot could be attached to and move with
the table. If they are large the pivot holder should be clamped to the
frame so it stays in line with the grinding wheel edges and table
travel axis. Then the pivot would have to be able to slide, or bend if
it was a rod rising from the floor.

Good Luck with it
jsw



I see that and it's a good, simple solution. Thankz!