I am installing a nifty Chinese DRO and set of glass scales on my grizzly 12x36. I am done , except the z axis chip shield. I am pausing here to check the accuracy of the set up, as I am running out of time to complain if there is a problem. I don't need a chip shield to test these, so it can wait. Currently I have a one inch standard used to calibrate micrometers and such. I have no Jo blocks. I have an er40 collet chuck mounted to the spindle with a nice ground flat face on it. It's the kind that came as a plate with an er40 chuck protruding from it, around the chuck is the ground flat. I have .0001 Interapid test indicator on a mag based noga arm. I have an Aloris knockoff qctp on the compound or I could also attach a vertical milling slide in place of the compound. I'm hoping to use this gear (preferably without making parts) to check the cross slide and carriage scales against the 1" standard. Something like hold the standard in a repeatable fashion against the chuck face and bring the indicator in till preloaded and zero it as well as the dro. Then remove the standard, bring the indicator in until it again reads zero and check the readout. I'm hoping to pick other peoples brains for solutions to holding the standard, indicator and general set up. Thanks for making my puzzle your puzzle.