The center finder is simple and effective, I like it, another project to add to my very long list

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I've made one of those dremel tool post grinder, they work ok, but they are not very rigid. I noticed a lot of flex with mine. I would move .0005" ahead and take multiple passes at the same settings and it would keep grinding away at each pass. If I was to re-do it I would look at rotozip tool which might be more rigid.
Thanks for posting.
Phil