Quick Edge and Center Finding
© Frank Ford 2006; Photos by FF

Most of what I do ain't exactly rocket science.  OK, nothing I do is rocket science. Anyhow, I do often want to find the center of a rectangular work piece so I can mill some feature, drill evenly spaced holes or whatever. Here's how I do it when I'm in a hurry, which seems to be most of the time the days I suppose.

First, I chuck up the end mill I plan to use, set the mill at slow speed and turn it on, running in reverse.

Then I simply slide the table over until the rotating cutter just bumps the edge of my piece. I can easily hear and feel it as it just begins to touch.  Sure, it makes a teeny little scratch on the side of my part, but this is a casual job, so that doesn't matter.  For more important work, I'll use a regular edge finder, of course.

I'll then set my DRO to zero on that axis, and repeat the process at the other end, noting the reading:


Dividing that number in half with my trusty little calculator-in-a-bag gives me the setting for the center of the piece. 

No need to consider the diameter of the end mill or anything else.  I scoot the table over to that setting and zero out the display. From then on, I can simply work from center to locate whatever I want.

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