CMM Calibration

[bpennings]

Does anyone know where I could find a somewhat detailed description of the tasks performed during an annual CMM calibration? Some individuals believe that a field service tech does not need to do this once a year but say every 5 years or so. You guessed it, they do not want to spend that much money (small company). I have never worked for a company that did not have the CMM cal'd annually, until now. They think I can do it (HA HA HA).

Thanks
Chillin' in CO

[John Kingston]

Looking at ASTM B89 would be a good start. Also, search for threads on calibration that Hilton Roberts has posted in. He is very well-versed in calibration and tracking how your machine is performing. His first question to you will be, "Do you have a "master part" or "widget" that you measure every day. Basically, measure the same part every day and chart the variation of some features. This alone will tell you when the machine is changing.

Here is a link to one of the threads this was discussed in.

[dwade]

I believe that with tracking the results with statistics of a measurement over a period of time as John stated is the only option for extending the calibration if your CMM.

I did this on a Mitutoyo and Zeiss and got to almost 2 years before I started seeing variation in my data (beyond microns). Both of these CMMs ran virtually 24/6 for several years.

Duane

[Hilton Roberts]

Looking at ASTM B89 would be a good start. Also, search for threads on calibration that Hilton Roberts has posted in. He is very well-versed in calibration and tracking how your machine is performing. His first question to you will be, "Do you have a "master part" or "widget" that you measure every day. Basically, measure the same part every day and chart the variation of some features. This alone will tell you when the machine is changing.

Here is a link to one of the threads this was discussed in.

What John said......

Just for the curious...I have a machine that I was getting ready to extend.

As I ran my 25 point baseline, point 19 and beyond went ape$hit.

I cleaned the TP200 and the stylus module and ran 10 more points with no change.

Thought either the machine got hosed or something wrong with the TP200.

Swapped out the TP200 and stylus module and order was restored.

Put in the old TP200 and changed the stylus module and order was maintained.

Problem isolated to a stylus force module taking a dump.

The lesson: If you do not know how well you measure your own "stuff" how can you afford to be passing judgement on products coming in to your lab?

Send me an email if you want a copy of my paper proposing a measurement process that will help you measure better and more consistently as well as save you money by not requiring an annual calibration if your machine is not changing.

We have not "calibrated" our machines in something like 3 years except for when we had some hardware break that required a calibration.

If you are careful to baseline a machine from the initial calibration by the manufacturer when the machine is installed, you do not need annual calibrations unless the machine is changing. You will not know that unless you chart.

That is the hard part of convincing American manufacturers the benefits of process control. They hear the money saving part but fail to heed the measurement part that requires monitoring of a process in order to determine whether or not the process is operating normally or needs assistance.

Lemmie know if I can help!

480-891-7263

[bw_bob]

I'll just post here so your not bombarded with e-mails. I'll take a copy please. Thanks

[JamesMannes]

Hilton, Count me in also. My notebook(s) are probably already filled half way with stuff I have copied from the forum from you but I'll gladly make room.
Sorry, emails are not provided by the forum anymore. Here's mine...

[Wes Cisco]

I'll just post here so your not bombarded with e-mails. I'll take a copy please. Thanks

Ohhhhohhhhohhhohhhh!!!!! Me too! Maybe you should post it as an attachment if it is not too big. TIA

[dwade]

Me three!!!! I mean me too!!

[email protected]

[Bill **********]

I highly recommend the read. It's well presented and it's in terms EVEN your boss could understand. Email him/her a copy and see what falls out of the trees.

Bill

[T Miller]

I also would like to take a look see...
TIA

[Hilton Roberts]

Ohhhhohhhhohhhohhhh!!!!! Me too! Maybe you should post it as an attachment if it is not too big. TIA

I think it is too big to post. Send me an email and I will follow the link back.
[email protected]

[John Kugler]

Mr. Hilton, as a regular of this forum, I very much look forward to your wit and wisdom on a daily basis. Your knowledge of CMMs and CMM capabiltiy is second to none, and I thank you for your dedication to this industry.

If you could be so kind, may I have a copy also??



Again, thank you so very much.

[Matthew D. Hoedeman]

Mr. Hilton, as a regular of this forum, I very much look forward to your wit and wisdom on a daily basis. Your knowledge of CMMs and CMM capabiltiy is second to none, and I thank you for your dedication to this industry.

Geez, ya don't need to kiss him rump THAT hard, man, it's giving it away to everyone!

I just stayed away from this in the beginning because Hilton DOES have all the answers in this area, I just waited for him to answer. BUT, your blatant rump-kissing just FORCED me to add my comment.

Thank you, and have a GREAT DAY!

[Hilton Roberts]

Geez, ya don't need to kiss him rump THAT hard, man, it's giving it away to everyone!

I just stayed away from this in the beginning because Hilton DOES have all the answers in this area, I just waited for him to answer. BUT, your blatant rump-kissing just FORCED me to add my comment.

Thank you, and have a GREAT DAY!

Matt......please take your meds.........you need them......really

Seriously, YOU have probably contributed more than any other single person to the success of this forum. I ALWAYS read your posts.

Thanks for all you do for the rest of us....

H

[#2#]

I too would be interested.