Giant micrometer - GIF

[Jon]

Giant micrometer.




Previously:

Double micrometer - photo
Braille micrometer for blind machinists - photos
Micrometer mug - photo
Mitutoyo can seam micrometer - photo
Calipers and micrometer Soviet Union flag - image
Giant micrometer tombstone - photo
World's Oldest Micrometer - 1776! Who made this thing??

[jimfols]

Recon what the resolution is, 0.500 inch?

[McDesign]

Yeah - that can't really be called a "micro"meter - maybe just "meter".
It's like the optical engineer I used to work beside, with a wooden yardstick he claimed was calibrated "in wavelengths of light".

Forrest

[jimfols]

"in wavelengths of light"

I would have had to ask the engineer 'what color'.

[McDesign]

Ah - we worked with lighting LEDs, so 450 nM - "royal blue".

All illumination LEDs actually make light at this wavelength, and are coated with phosphor to absorb some portion of this wavelength, and reradiate it at a variety of longer wavelengths, or colors. Our eye mixes all this together as various degrees of "white". There are a couple of boutique LED makers that use a 405 nM "pump" to get some more energy in the near UV area.


He was a smarter guy (a couple Masters degrees as well), but I think I have more patents.

That's better, right?

Forrest

[old kodger]

Depending upon how "stiff" the arc framework is the resolution might be a lot less than .5". I wouldn't be surprised to find it down to nearer 10 or 20 thou.
The problem is at what time of day he seems to be measuring steel, and the gi-crometer looks like aluminium coefficients of expansion would play havoc with that
I suppose it could be made of titanium.

[Paul Alciatore]

Mechanical clocks (and electronic ones for that matter) can be compensated for temperature changes. Why couldn't the frame of a micrometer also be?

[suther51]

It may have to.be calibrated often, perhaps multiple times a day. The extra long "dumb" anvil might play a part here as a way to efficiently calibrate. Just a guess

[old kodger]

maybe even recalibrated before every use

[Jon]

Large measuring instruments. Westinghouse Electric Corporation. 1910.

Fullsize image: https://s3-us-west-1.amazonaws.com/h...s_fullsize.jpg