Calibration of Cmm

[Darren Johnson]

Is it possible to have someone outside of Brown and Sharpe to calibrate the cmm? I have heard that they are the only people that can calibrate it correctly. If anyone knows of anyone other than brown and sharpe that can calibrate it correctly please let me know. Thank you in advance.

[BSchwark]

Sure anyone that does Cmm calibration should be able to verify your machine and calibrated it. But if there is a problem most places can not correcte it and will tell you to contact the manufacture or repair facility to correct the problem and calibrate it.
If you know your machine is solid and stable? Go for it. If you are not sure you need to get someone that can make adjustments and error map your cmm. Most adjustments on todays machine are done electronically.

BS

[bw_bob]

wBSs

[jjewell]

Well Darren, it depends on the generation of your controller.

Only ppl that can calibrate it correctly ? Please....

The newest controllers built in the last 2 years (I think) have a new password system in order to access the correction map. If you can't get through that (which nobody can to my knowledge) you can't make the corrects to the map.

Any quality company can certify the accuracy of the machine, but can't make corrections on the newest controllers.This , in my opinion, is crap and should be illegal.

On the other hand, if you have an older controller, anyone qualified that is an independant, can correct the map just fine. Its not rocket science, the software available does most of the work for them in arcseconds.

Make sure if you choose to use an independant, you get good references.

HTH

Jim

[Darren Johnson]

Does anyone on the board know of any companies with a good reputation that does calibration of cmms? I only know of one place and that is Cmm technology's. I also know that they do not sell the brown and sharpe software. Again Thanks for the help.

[craiger_ny]

Conway Gage in Canandaigua, NY does excelent work (service and cal). Rodger used to work for B&S and is very resourcefull. He also sells a nice variety of CMMs and measuring equipment. I'll PM you his # because I'm not sure if he'd approve of me posting or not. I'd recommend him to anyone.

Craig

[cmmguy]

Conway Gage in Canandaigua, NY does excelent work (service and cal). Rodger used to work for B&S and is very resourcefull. He also seels a nice variety of CMMs and measuring equipment. I'll PM you his # because I'm not sure if he'd approve of me posting or not. I'd recommend him to anyone.

Craig

WCS

[Hilton Roberts]

There are companies that can calibrate your cmm. There are more that can tell you what is wrong than those who can actually repair/adjust the machine to original specs.

I have had the mis-fortune of using people in the past that would tell me something was wrong and then directed me to the manufacturer to get things fixed.

In most cases, these were people who at one time or another worked for the manufacturer in question. When some of these companies downsized, a lot of good people were let go. The bad thing is that some of those folks let go were good at one thing. Maybe electronics was there forte or perhaps mechanical adjustments. DEA used to send electronic techs as well as mechanical guys out to do installs and calibrations.

Brown and Sharpe usually sends one person to do the whole thing.

I have had very good luck using them for my calibrations. As with any company, you will run across technicians who are head and shoulders above the rest. If you have a background in dimensional metrology, you are a leg up on the problem.

The other issue that sometimes comes up is the problem of technician "A" doing the original work on the machine and technician "B" following behind.

Normally, this results in one person liking certain adjustments to one side of the tolerance band than the other. What usually happens is the second person readjusting things because settings are not where he prefers them.

This sometimes leads to overadjustment of parameters that are in tolerance to one side of the tolerance band or the other. Sometimes that leads to a machine changing because certain variables are adjusted that just should be left alone.

Boiled down to the essential, perhaps your machine is not in need of adjustment at all.

If you have a part that you measure periodically both over the short term and the long term, you can determine if the machine is operating within the bandwith of variation that has been determined over time.

If you do that and you really find the need to have someone calibrate your machine, you can....by charting....determine if the calibration improved or degraded your machine.

I have worked in metrology since 1965 and one of the most interesting things I have observed is what happens when technicians recalibrate their own work.

Almost invariably, fewer adjustments are made when one's own work comes back into the lab.

So...back to the question. The best solution is probably to have your company send your maintenance folks to school to learn how to calibrate and adjust your machine. They would then have all the tools required to do the job and do it right. Second best choice ( this is what I do ) is contract with Brown and Sharpe, and have them work on the machine. They have the skills and access to the parts and tools needed.

I just make sure that I chart my machine so I know if it needs to be worked on or not.

I have control charts dating back to the time I did acceptance testing at the factory before delivery.

I have not calibrated my Xcel 7-10-7 machines since 2004 and I have the data to show they are stable. I do not plan to calibrate until 2007.

I might suffer a hardware failure or crash and require a repair and calibration, but until that happens and as long as my charts do not indicate a shift in the machine, I will continue to monitor the performance of my machines and calibrate when the charts tell me the machine has changed.

HTH

Hilton

PS: Any questions, give me a call at 480-891-7263

[Andrew Gardner]

I use Midwest CMM here in Chesterfield MO. for my Brown and Sharpe.

[Arenw]

For what it's worthe,we have used CMM Technologies for the last 3 years, and they have done us right each time.

[Darren Johnson]

Thanks again for the reply's. We are a company of about 50 people day and night shift combined. Unfortunatly we only have one maintenece guy and I am pretty positive he does not want the responsibility to maintain our cmm. I know the person that has been coming out to calibrate our machine is only telling us if the machine is repeating or not. Thanks for all the answers and opinions I really appreciate them all.

[rangerboat72]

Brown and Sharpe usually sends one person to do the whole thing.

I have had very good luck using them for my calibrations. As with any company, you will run across technicians who are head and shoulders above the rest. If you have a background in dimensional metrology, you are a leg up on the problem.

I have to agree with Hilton on this one. I've been using B&S service for the past eleven years. We've had some really bad and some really good technicians working on our equipment. Nine times out of ten the bad ones really weren't bad, they just weren't knowledgeable of our particular machine. It seemed like the ones that were sent down from Michigan had a lot more knowledge of the particular machine/equopment than the local ones only because they did a lot of work for the BIG THREE in Michigan.