I was lucky to be first on site when RacingTadpole gave away 3 micrometers recently. Hey RacingTadpole many thanks. Had a great time fiddling with these.

Got bored tidying shed, its been 5 days in a row now (my wife encouraged me to tidy shed) so started on the Micrometers.

The Moore & Wright micrometer has some clever ideas built in, some photos below, I guess there was a bit of thinking and evolution taking place to get designs like this.

If you have pulled apart micrometers then look away now, you will be bored. If you've not seen the guts of a micrometer there are some clever bits.

M & W as received.

Photo 1 After cleanup with kerosene and scotchbrite
Photo 2 - inbuilt Fractions to thousandths conversion charts engraved on the handle - I reckon this is great as working off fractional plans and converting to thous drives me batty
Photo 3 - The Claw, it was originally black and the M&W logo shone through as it turned back to silvery metallic. What is the claw for ? The only thing I could think of was if you want to turn two parts to identical diameters and the first part is 0.5346" you cannot measure that, so just set the claw and make second part to match the claw. Is that correct ?
Photo 5 & 6 - great idea, adjustment mechanism to ensure the main threaded bar is firmly held by the receiving thread, the collar screws onto a slightly tapered slitted external thread which compresses the internal thread onto the main threaded bar. Difficult to write, easy to see when the bits are in front of you.
Photos 7,8,9 - Locking mechanism, works well - reminds me of a pinchuck mechanism. I probably didn't understand how it worked and was thinking the thread was too tight when I first used it. You only have to move it less than 1mm to lock the main mechanism.

Had a great time pulling this apart cleaning and oiling - do I need special oil for delicate measuring gear - I used 3 in 1 - what do you folk use in your micrometers ? Calibrated it on a 1" disc and working fine now.

The other two are cleaned and running freely on the main measuring thread but the fine control ratchets are both stuffed . I cannot remove the ends to see whats wrong. Will think for a bit and try again next week - any thoughts ?

Bill
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