[deadlykitten]

hello instead to deliver o300+0.056+0.088, i scored o300+0.020+0.050 ( 10 parts so far )

tolerance was ok, but baseline is offset ... you can imagine what discusions poped up don't you ?

i used an analog micrometer, calibrated over 3 vices 100 mm each, and seems that the vices are not ok ...

if this was an internal diameter, using an internal bore gauge, with 0.001 accuracy, would have been ok ... but the outside micrometer has 0.010 divisions, and different persons can get different results with it, especially at such diameter

please, i need practical advice, how to get more precision at such measurings, how to make it repeatable between different persons, just like an internal bore gauge is

i was expecting such a thing, it was just a matter of time; for such parts with 0.03mm tolerance, i wish to achieve accuracy at a level of preferably 0.003-0.005 for big diameters / kindly

[deadlykitten]

seems the jo-blocks where smaller with 0.025, after inspection at 2 separate locations : metrology lab, and cmm

to avoid error caused by micrometers, i quickly made a snap-gauge

will follow discusions with client, see what's next hope for the best

[Mecanix]

Greater than 100mm in the <10um tol are CCM jobs normally. Presumably you already have a fully error-compensated screw as a reference somewhere in the shop, on-machine probing is the second option.