Originally Posted by
FBinNY
Sutherand is offering a tape measure depth gauge set exactly as you describe. I believe the tape calibrated in diameters so you don't even have to divide by Pi. (if it isn't he missed a good move) All this for the bargain price of USD $75. I don't own anything dedicated to this job, so use whatever steel tape is handy, and make a depth gauge from a piece of cardboard, which I mark and measure.
Been doing it this way for almost half a century and it still works fine, though when everything is computerized, and pens no longer made, I might have to find a new depth gauge.
Yeah- I use one of those steel wind-up surveyor's tapes, which may not be that accurate after all. And I don't have any desire to buy a $75 tool when the diameter works just fine. But I *do* have a set of dial calipers with a depth tang on the end ($10 at harbor freight) for when they no longer make cardboard and pens
