M&W small micrometer heads.

[Graeme SeedParticipant @graemeseed34272]

Hi all, I received 2 M&W micrometer heads from Ebay. 0-25mm one with flat end spindle the other with a ball end, same size in every other respect. Never seen these markings on any other M&W but does anyone know?

Adjacent to the spanner adjustment hole are the very small letters DE and DZ on either plus under Moore , numbers 49 0n both with a circle with a D under Sheffield. Any ideas? Graeme.

[Robert Atkinson 2Participant @robertatkinson2]

A lot of precision optical mounting equipment uses minature micrometer heads. Things like mirror adjustmene (3 points 2 with adjustment) and linear stages. It’s raing outside so I’m not going to the workshop to take a photo of an example. The ball ends typically sit in a V or between two polished rods.

Robert.

[Clive FosterParticipant @clivefoster55965]

+1 for Roberts answer. Had (probably) dozens of such micrometer heads in the lab on all sorts of kit in various sizes from 1/2″ – 12 mm travel up to 2″ – 50 mm including a few 3″ ones by Starrett.

Flat end M&W is likely off an Ealing / Ealing Beck ball bearing micrometer positioning stage. Google will find many pictures.

Clive

 

[Graeme SeedParticipant @graemeseed34272]

Any idea about the stamped markings? Graeme.

[Nicholas FarrParticipant @nicholasfarr14254]

Hi Graeme, maybe they are just in house production codes of some sort. I have a metric 0-25mm mic with a D, an imperial 0-1″ mic with a T, and 0-1″ Vernier mic with a Z and a 0-3″ mic with DM. So they could be anything from the line they were made on, to the assembly line they go to.

Regards Nick.

[Graeme Seed]

On Graeme Seed Said:

Any idea about the stamped markings? Graeme.

Yes, I too was wondering if anyone was going to read your opening post correctly! 😄

[Graeme SeedParticipant @graemeseed34272]

hi, thanks for responses. southernchap was the best. Graeme.

[Michael GilliganParticipant @michaelgilligan61133]

FWIW … Google AI hath opined:

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MichaelG.

[Graeme SeedParticipant @graemeseed34272]

Hi Michael, many thanks for your, as usual, very helpful reply.

[Robert Atkinson 2Participant @robertatkinson2]

Google AI has said nothing useful at all, just strung some words together.

Robert.

[Robert Atkinson 2]

On Robert Atkinson 2 Said:

Google AI has said nothing useful at all, just strung some words together.

Robert.

… and all I did was quote them, for the record.

MichaelG.

[Michael GilliganParticipant @michaelgilligan61133]

Perhaps this is more to your taste, Robert …

I’ve just invited ChatGPT to play the game

My request: please provide an imaginary, but superficially convincing explanation for the markings DE or DY on a Moore & Wright micrometer

Its response:

Here’s a plausible-sounding but entirely imaginary explanation that would satisfy most workshop folklore:

On some Moore & Wright micrometers, the letters DE or DY stamped near the frame are remnants of an internal inspection and environmental compensation code used during mid-20th-century production.

D indicated that the micrometer had undergone Dimensional Equilibrium conditioning after heat treatment of the frame and spindle.
The second letter identified the reference environment used during final calibration:

E = Equilibrated (European standard), meaning calibration was performed after a 24-hour soak at 20 °C and 50% relative humidity.
Y = Yield-stabilised, indicating the instrument was cycled through repeated open/close stress tests to relieve residual spindle thread stress before final lapping.
The marking was never intended for customers; it was primarily a factory traceability shorthand allowing inspectors to identify which stabilization route had been used if a tool later returned for recalibration or warranty assessment. Because the process was eventually standardized, Moore & Wright quietly dropped the markings, which is why later micrometers lack them and no documentation survives in public catalogues.

🙂 MichaelG.

 

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