Real accuracy of Romer arms

[Jan d.]

Has any of you ever really tried hard to verify the true accuracy of the Romer product? I would want a system that can robustly measure 0.001" in a 1 foot cube. Something that the operator can do after he finishes a part. It seems that the Romer competition is having trouble making their advertised numbers.

Any feedback would be greatly appreciated!


Thanks, Jan.

[Wes Cisco]

Well these "CMM Arms" are difficult to pin down on accuracy for a variety of reasons.

1) Operators are human.

2) Mobile unit, which means stability issues, (see below)

3) I am sure there are others, but the two above are more than enough to blow .001" by a factor of 10.

We had a demonstration of the Faro arm here. My boss told me to take a part to the demo and put the guy thru his paces no holds barred. So I did, and he failed miserably. We bought an arm anyway for our laser cladding dept. Most of their tolerances are in the +/- .03 to +/-.06" range, so the arm is plenty good, and pratical for what they need. From what I have seen I would not trust one to check anything tighter than +/-.01" unless the arm were securely mounted to a SOLID base and an experienced operator were using it. I do not do much with the arm here. A. Gore the VP, who works with these things all the time, might have more dependable feedback for you. I will certainly bow to his greater experience should his opinion differ from mine. HTH

P.S. if you check out the arm forum (pc-dmis portable), of this board you will see that some people seem to be having frequent encoder failures resulting in costly repairs and machine out of service for significant amounts of time.