Joe Piro
Well-known member
I sent off three analog vernier micrometers to Mitutoyo after a fire (I called and got permission to send them in.). The plastic cases were not melted but there was some corrosive fire water entry into the cases.
Mitutoyo sent them back and refused to work on them.... wanted to sell me new ones at full list price. I went on line to read about re-building and calibrating mechanical micrometers and discovered that they are a basically simple mechanism (precision screw thread) that is hard to mess up unless they are improperly used or made out of inferior materials (my opinion only). So I have overcome my fear of servicing them. The 25mm to 50mm still turns like velvet and I'll just clean, re-oil, assemble and calibrate with standards. Same with the 75mm to 100mm. The chrome is good on those also. I'm surprised Mitutoyo didn't at least service those two.
However the 50mm to 75mm is seized and I can't unscrew it. (See photos) Your best advice may be to spend ~$150 and buy a new one, but I hate waste.
I took off the ratchet and also the thimble lock lever. For a week now, I have dripped PB Blaster into it several times every day through those holes and around the barrel and then tried to persuade it.... but it won't move. It feels like the thimble lock is engaged, but the screw and lever are out.
(I need to resolve this because very soon I have to rebuild the four cyclinder motor from my Nissan truck.)
Any suggestions? (keep it clean please)
Mitutoyo sent them back and refused to work on them.... wanted to sell me new ones at full list price. I went on line to read about re-building and calibrating mechanical micrometers and discovered that they are a basically simple mechanism (precision screw thread) that is hard to mess up unless they are improperly used or made out of inferior materials (my opinion only). So I have overcome my fear of servicing them. The 25mm to 50mm still turns like velvet and I'll just clean, re-oil, assemble and calibrate with standards. Same with the 75mm to 100mm. The chrome is good on those also. I'm surprised Mitutoyo didn't at least service those two.
However the 50mm to 75mm is seized and I can't unscrew it. (See photos) Your best advice may be to spend ~$150 and buy a new one, but I hate waste.
I took off the ratchet and also the thimble lock lever. For a week now, I have dripped PB Blaster into it several times every day through those holes and around the barrel and then tried to persuade it.... but it won't move. It feels like the thimble lock is engaged, but the screw and lever are out.
(I need to resolve this because very soon I have to rebuild the four cyclinder motor from my Nissan truck.)
Any suggestions? (keep it clean please)
