One tool - two uses

[mklotz]

Marv,

The concept seems simple and it should be useful. But do you have any tips on how to machine it with good accuracy? Yes, I know, touch off on one side and go half the diameter. But just how accurate is that going to get you? Two thousandths may be the limit. I would like to have it down to a few tenths.

Surely you jest, Paul. Two tenths accuracy on something you're going to use to make punch marks? If you want that sort of accuracy use your mill/DRO or a jig borer. How do you intend to make layout lines with tenths accuracy?