You can click on the images & enlarge them. The J T Slocomb Co (bottom mic) was a highly regarded tool company noted particularly for their unique design of micrometer. They were located in Providence RI, the same town as Browne & Sharpe, but no connection. This one carries patent dates of May 12 - 96 & April 13 - 97. These dates were marked for some years so do not date it other than the design, but may well date to pre WWI.
The Lufkin I acquired in abused condition. It had apparently been locked up at some point as it has plier marks in the thimble knurling. Fortunately, all the damage was external & of a cosmetic nature. It was still extremely hard to turn when I got it, priced accordingly. As everything on it was steel I soaked it in acetone & managed to get it apart & cleaned up. I then decided to do an experiment on it. As I put it back together I oiled it with 3-in-one. That was more than 20 years ago. It has been oiled with nothing else since.
I acquired the Slocomb about the same time, but in better condition I just cleaned & oiled it, using Starrett Tool & Instrument oil.
I use both of these fairly often, though not on a daily basis as used my standby micrometers while still employed. Both have that "Sweet" feel of precision that only a machinist can fully appreciate. Right now today I would not be afraid to use either on any job which had no less than 0005" tolerance. About the only micrometer, I ever owned I would guarantee closer than that was a C E Johanson.
I have measured a lot of gun parts with a one inch micrometer & oiled a lot of guns in the past with 3-in-one so do not feel this off topic.
