Technical Drilling a hole in the exact center of a disc

http://progress-is-fine.blogspot.com/2016/05/shopsmith-center-finder.html

 

I love this thread....

 

i see what you did thar'

 

If you can buy donut holes at Dunkin Donuts; you can drill a hole in the center.

 

57 heap has the easiest way

 

Actually, I'm just about done with phase one of my project. If you have followed the entire thread, you know that I am making an analog for the old Mallory "Big Brass Condensers". I used the one disc I did drill for my prototype, because it's not that bad., just not something I'd like the general public to see. I have been running the prototype on the '51 Merc engine on my test stand for the last couple of days. It seems to function properly. We're going to pull it apart after a few more hours running and see how everything stands up. After that, I want to build a few "pre-production" units that I will want to distribute to some willing volunteers who will run 'em hard to see if the reliability is there.

Stay tuned.

Moriarity, Thanks for the kind offer. Breezy Point to Mound is a bit of a go for just a few holes at this time, but if I continue having problems, I may take you up on this. I hit the twin cities a couple of times each summer. I am originally a Wayzata guy, so it sounds like a natural.

 

Yes, 57 heap has the most accurate method. But you can buy or make your own "center finder."
http://makezine.com/2011/04/26/tool-review-robert-larson-800-2875-center-finder/

http://www.instructables.com/id/Make-a-Center-Finder/