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+--- Thread: Measure twice, cut once.... what the heck? (/thread-2074.html)
Measure twice, cut once.... what the heck? - roundrocktom - 04-03-2014
Had to bore out a 1/2" thick aluminum plate to 3.125".
Well, centered it up on my little jig plate. Set up the big boring head, and cleaned it up. Mentally thinking I need to take about 035" off, but I like to make a first clean pass to get a good measurement. I was about 0.060" under.
I should have stopped there and questioned it...
Cranked in 0.030" cut.... and I'm 0.040" under... huh? Cut another 0.030"... and I'm 0.035" under.
Locked the set screw, measured the mating piece... and it was reading smaller, but had about 0.050" of sloop. :(
Yep, cheap electronic caliper I bought three years ago for $25.00 on sale. It's served me well.... but no two readings are the same. Hind sight, I should have stopped and used a known standard when the numbers started to look funny.
Think I'll get $30 for "great condition, lightly used" on eBay. Maybe I should send them to Oxtool as a thank you gift. :) I'll do a little silver soldering first so they can not every lie again.
Ay, caramba.
Hmm, Enco has the nice Mitutoyo Calipers on sale, time to bite the bullet. I really need to add a 0.000 1 indicator, but that can wait to next month.
RE: Measure twice, cut once.... what the heck? - PixMan - 04-04-2014
I want to see the video of the repair on the faulty ones! I recall seeing a video showing recalibration of some cheap digital calipers....using a 2lb dead blow hammer.