Ebay’ed some used mic’s

@Bone Head Tried your method on an old Brown & Sharpe .0005" I had in the toolbox and it definitely helped with the slow action. Thanks for the tip! also found a roller tip and 90 deg. attachment I forgot I had. The face was pretty scuffed up but I used a 3000 grit polishing pad followed by some plastic lens polishing compund and it cleaned up pretty nice.
C010FC9A-8886-4187-9C25-13D297C10048.jpeg
 
Your roller tip is the trick to measuring across a surface and getting a reading without a .0001" gauge getting crazy.
 
Pawn shops sometimes have good tools, other times new prices for junk tools.
I bought this old 0-1“ Craftsman mic in new condition, very nice for $20. years ago.
Turns out it was made by Scherr-Tumico.
A quality tool & a joy to use.
 

Attachments

  • CCD745BD-DCA6-48C2-8177-63F6729D8849.jpeg
    CCD745BD-DCA6-48C2-8177-63F6729D8849.jpeg
    403.6 KB · Views: 7
@Bone Head I finally swung by our metrology lab and talked to my buddy and he said exactly the same thing you did about cleaning with PURE isopropyl alcohol (not rubbing alcohol, for those that don't know there's a difference) and NO oil at all. He included micrometers in that statement btw. He said that ONLY if kept in a case 99.9% of the time, then MAYBE use only the smallest drop of oil like starrett or 3in1 or gun oil on the mic threads but NEVER on the other gauges. Even then he wasn't too keen on it. He was adamant about that. For calipers he recommended cleaning the rod and way with alcohol and using a metal paste polish with silicone that Starrett makes for this purpose but again, NO oil. That goes for the flat style drop gauges too. According to him, thats what causes most stiffness/resistance on those. Oh, and to the concern about dry operation contributing to accelerated wear, he said he hasn't seen any in almost 30 year old daily used pieces. So, for all you habitual gauge oilers, listen to two veteran metrology guys and put the oil bottle down! lol Thanks again @Bone Head.
 
Last edited:
"....listen to two veteran metrology guys and put the oil bottle down!..."

That guy's one, but who's the other? Bahahahahahahahaha!
I'll disagree with him about one minor detail. Starrett lubricants are good for their purposes, but a drop of Starrett oil on a mic's threads every six months or so, then a quick wipe off is good over the long run.
 
Bone Head said:
"....listen to two veteran metrology guys and put the oil bottle down!..."

That guy's one, but who's the other? Bahahahahahahahaha!
I'll disagree with him about one minor detail. Starrett lubricants are good for their purposes, but a drop of Starrett oil on a mic's threads every six months or so, then a quick wipe off is good over the long run.
Click to expand...
Lol. I think there may be some amount of headache prevention over gauge longevity going on there too considering the deep pockets of this place (I'm at work atm) so take that with a small unlubricated grain of salt. I'll probably keep my mic's VERY lightly lubricated as they'll spend most of their time in cases.
 
The issue with lubrication is two-fold: It turns gummy and it attracts abrasive grit. Good synthetic instrument oil won’t turn gummy—it will dry first and leave no deposit. But grit is a concern. That’s why I put only a watchmaker-sized drop only on pins using a needle oiler. This applies to indicators that use clockworks. I can’t say I’ve seen indicators that wouldn’t work because of worn holes, but I have absolutely seen plenty of worn holes.

The only reason to keep mics oily is to prevent rust, but there are better ways to do that that don’t attract grit.

Rick “noting that Mitutoyo, at least, uses grease (!) on sliding pins and shafts from the factory” Denney
 
Last edited:
You must log in or register to reply here.
Back
Top