On Tue, 25 May 2010 17:29:23 -0500, the renowned "Karl Townsend"
wrote:


"Spehro Pefhany" wrote in message
news

Sorry for the metal content, but there might be someone here who knows
the answer!

I would like to find the center of a 6" metal disk (center the mill
spindle precisely over it).

Here is my plan...

Use an edge finder and find 3 points at roughly 45 degrees to the
center by moving only the X axis, then only the Y axis (forming
a right triangle) with the hypoteneuse over the disk. Go halfway on
both X and Y between those pairs of X and Y numbers.

Does this sound like a reasonable plan?


I do this a lot. You're over thinking it.

put the spindle about at the cneter by eye.
Zero X axis by going to one edge with edgefinder
Find to other ege with edge finder. record reading and move exactly 1/2 way
back.
Zero Y axis at one edge with edgefinder
Find other edge with edgefinder, record reading and move exatly 1/2 way
back.

You're at the center of your circle.

Karl


Thanks, Karl and Tim!


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
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