Calibrating an inside micrometer

#tools #machining
Hi everyone. I had this old Bowers internal micrometer offered in a non-working condition. In this video I will take it appart and find out how to calibrate it.
I hope this might help someone with a similar micrometer.
00:00 Introduction
00:27 Tool description
01:09 Condition check - out of calibration
02:43 Disassembly and inspection
06:46 Fixing spindle backlash
08:02 Reassembly
11:46 Calibration
15:28 Final check

[@cooperised]

For a small and new channel your video production is really good. Keep it up! Hopefully you'll steadily start to get the exposure your content deserves.

[@multirole240]

Very well presented and informative. Thank you for making the video

[@nbrworks]

Hi! Thanks!

[@user-be4nj9ol3o]

Very informative. I have the same mic but in inches 2"-3" This is new to me and having a heck of a time trying to read this darn thing. No instruction or anything. If you could share a tutorial on how to read this it would be fantastic !

[@nbrworks]

Thanks, glad it was helpful. I don't know how the imperial version is, but the metric version is like other micrometers. If it helps, I think there are some good videos here on youtube on how to read a micrometer 🙂

[@Zuul88]

Hi, I really like your videos! Keep it going! On this one, either you calibrated it to the wrong reading (37 on the caliper and 31 on the calibration ring) or you used other measuring 'anvils'?

[@nbrworks]

Hi, that's a good question. Maybe it isn't clear in the video, but the micrometer is marked 25 to 31 on the left scale and 31 to 37 on the right. Each scale to be used with the specific set of anvils provided in the box. I was using the smaller ones and looking to scale on the left that goes up to 31mm. Maybe that's why the confusion' I didn't realize that wasn't clear in the video. Thanks!

[@vikingsofvintageaudio7470]

Baby Chuck chu chu chu chuck, baby Chuck..,😅