I am having some trouble with measuring accurate Diameter size, I have read some threads on this type of thing but the solutions provided pertain to mostly Bridge Type CMMs and I am using a Romer Arm. So I'm interested in any tips you guys may know of to get more accurate results. ... oh and it seems I have more trouble when working on sheet metal parts and I can imagine its due to the thickness of the material. Thanks in Advance
no, we don't have a laser... wish my owner would spring for one but I don't see that happening this century. As far as the one point method... I use that all the time and it's great for position but not so much for size. The hole has to have an absolutely perfect edge and the "plane" that you measure has to be nearly perfectly flat to get an accurate diameter size since the software uses math of the probe size and plane position to get the diameter. Any variation at all will throw (and I use English standard inches here) the diameter up to several thousandths just depending on the severity of the defect on the part. Even deburring a part can throw the size/position a bit as a dotco (sp?) will leave a small chamfer along one side or imperfect chamfers due a concentricity issues. Using a hand whip for deburr will really cause havoc.
no, we don't have a laser... wish my owner would spring for one but I don't see that happening this century. As far as the one point method... I use that all the time and it's great for position but not so much for size. The hole has to have an absolutely perfect edge and the "plane" that you measure has to be nearly perfectly flat to get an accurate diameter size since the software uses math of the probe size and plane position to get the diameter. Any variation at all will throw (and I use English standard inches here) the diameter up to several thousandths just depending on the severity of the defect on the part. Even deburring a part can throw the size/position a bit as a dotco (sp?) will leave a small chamfer along one side or imperfect chamfers due a concentricity issues. Using a hand whip for deburr will really cause havoc.
