MICROMETER MK-50 «St.James Minn. U.S.A. », USA, Approximately 1906

MICROMETER MK-50 «St.James Minn. U.S.A. », USA, Approximately 1906

In the exposition of the Museum of Industrial Instruments MICROTECH there is an American micrometer "Tubular Micrometer Co." famous firm "St.Lames Minn.U.S.A.", the modern name of which is known as "Tumico".

The 110-year-old American micrometer from Tumico has significant and interesting differences:

The bracket has a smoothly rounded shape (unlike the flat brackets of pioneer micrometers "Brown & Sharpe", USA);

The micrometer has an extremely low weight due to the use of a hollow bracket welded from a bent thin steel sheet;

Tubular micrometers with a hollow bracket are made according to the American patent Pat.US797409 from 1904 to the present!

According to users of the floor, the micrometer bracket retains its shape well for 30… 40 years and provides minimal measurement error.

The micrometer also has a rattle to ensure a constant measurement force.

According to the trends of that time, there are no thermal protection pads and the date of manufacture of the micrometer on the bracket field of the American rare micrometer.

A feature of a rare micrometer is the lack of a serial number.