I just made three gauges with three coins using this tip. It was easy to use an old quarter, an old penny, and an old dime to get right on three-place accuracy. I'm storing them in my truck's change container. Philbert, you just plain amaze me sometimes.
Proof is in the pudding. A sawyer gave me a used 36" Stihl bar last month that he says was "grooved out" and too wide to use. I checked it with the old quarter all the way around the bar. Good fit all the way and the groove's depth was fine also. So, I might just add a new sprocket nose. Amazing what sawyers throw away. I'll use this bar myself in early spring.