Lufkin 680 inside micrometer set

[twhite]

The knurled end pieces should be threaded allowing calibration. They will be snug moving obviously. I use inside mics everyday at work. When you get the feel they are good to a few tenths. I check calibration with a mic every few days. Then verify my measurements on our CMM.

Indispensable tool in my book.


Cutting oil is my blood.

 

[Batmanacw]

The knurled end pieces should be threaded allowing calibration. They will be snug moving obviously. I use inside mics everyday at work. When you get the feel they are good to a few tenths. I check calibration with a mic every few days. Then verify my measurements on our CMM.

Indispensable tool in my book.


Cutting oil is my blood.

The ends are threaded but there is no way to lock them from movement once screwed in.

 

[Batmanacw]

So.... 3 visits to the flea market and 3 sets of internal mics..... insanity!

$25 Starrett





There is some minor wear on the bump on the back so I had to calibrate each rod. I got them all within a couple tenths except the rods I had to do with my calipers because I only have up to 6" micrometers. They are really in near perfect condition.

These are all three sets together.



This is all four sets I own.

Top is from Sherr Temico that I've had for well over 20 years. Left bottom is Starrett, middle bottom is Lufkin, and bottom right is the odd Sawyer set.

 

[T Bredehoft]

I got called on once to mike a bearing seat in a machine, nominally 48 inch diameter. Yeah, my mike set (an old tubular Starrett) would accomiade it, I spent about half an hour inside the housing, (with a 30 inch hole in place of a floor) to make sure I got it right. Yes the machine was in place, I was about 12 feet above the floor, inside the machine. No one ever mentioned how well the bearing fit, must have been OK.