Do any of you use a granite plate offline to check parts? If so, do any of you have a thread insert pattern on it? I am about to by one and am trying to decide what would be the most helpful hole patter to have. I was thinking about staggering some 3/8-16 inserts along one short edge about 3 inches in. 3ft*6ft*12inch granite.
We do plate layout OFF of the CMM all day long to check stuff that doesn't need the CMM/will be quicker off of the CMM.
If you're referring to using the granite TABLE that the CMM has...remember...that IS NOT a surface plate..it is just an expensive rock that has not been calibrated to any spec nor is it certified to be square to the CMM itself.
Our CMMs all have aluminum plates with 1/4-20 holes spaced 0.5in from one another and we use it for fixturing/part location purposes.
We do plate layout OFF of the CMM all day long to check stuff that doesn't need the CMM/will be quicker off of the CMM.
If you're referring to using the granite TABLE that the CMM has...remember...that IS NOT a surface plate..it is just an expensive rock that has not been calibrated to any spec nor is it certified to be square to the CMM itself.
Our CMMs all have aluminum plates with 1/4-20 holes spaced 0.5in from one another and we use it for fixturing/part location purposes.
not on any new machines, for sure, but WAY back in the day, before there were table maps and so forth, the tables had to be 'flat' or the machine could never be used accurately under any conditions. They used to be flat, within the specs of the machine, but that was back when they gave a +/- tolerance (only) for the machine, like my Validator (almost 40 years old).
