Micrometer setting standards

[Pete.]

Wasn't meaning to pile in on you grim_d, it's just that many people don't even understand the difference between accuracy and resolution much less the requirements for very accurate measurement (and you can count me in the latter). I have a set of four standards that came with a 0-4" moore & Wright micrometer, but I have never actually used them. If I'm shooting for a 'fit' on a part I'll always have both parts so a comparative measurement is all I need. If I was working to a print - which in reality never happens - then that's a different matter altogether.

BTW bearing races make great standards, they are ground very accurately on width.

 

[grim_d]

I thought it was women's underwear of washing lines

That's your story and you're sticking to it eh?

Wasn't meaning to pile in on you grim_d, it's just that many people don't even understand the difference between accuracy and resolution much less the requirements for very accurate measurement (and you can count me in the latter). I have a set of four standards that came with a 0-4" moore & Wright micrometer, but I have never actually used them. If I'm shooting for a 'fit' on a part I'll always have both parts so a comparative measurement is all I need. If I was working to a print - which in reality never happens - then that's a different matter altogether.

BTW bearing races make great standards, they are ground very accurately on width.

I understand that, if replicating a part as long as the 2 measurements match, the calibration of the device does not matter as long as you use the same device.

If measuring something that I did not make, e.g for serviceability, I'd like my gear to be as accurate as possible. I initially bought my first micrometers for measuring bearing journals and shim buckets, I still haven't built that engine but that's beside the point. At least if the gear is accurate then the only thing left to go wrong is the gorilla using it.

Good idea on the bearing race, need a bloody big bearing for a 6" mic though!

 

[Pete.]

Shim buckets are usually ground to very fine limits and surface RA.

 

[ronan]

I was looking at these earlier.

http://www.ebay.co.uk/itm/Mitutoyo-...091113?hash=item3608284629:g:hLkAAOSwknJXxYEZ

 

[grim_d]

I should have said cap shims rather than bucket shims to avoid confusion there. That's my mistake.

I meant the non adjustable type. So adjusting clearances requires ordering new shim caps the right size. (or finding ones the right size!)

Though we have been treating them as buckets using hole punched feeler gauges as shims. Sounds gash, and it is, but works.

@ronan - that's a nice set. Saw it earlier, shame it's missing the 2 I actually need! The gnomes got them.