posted 02 April 2001 01:44 PM               

The more complicated answer is NO, you don't have to send them out. The context of this is that you could choose to do them internally. If you make that decision, you need adequate procedures, properly traceable standards, adequately trained personnel to do the calibrations, and environment controlled adequately to assure your calibrations are legitimate (regarding environment). If you have people with adequate background who could be trained to calibrate them in-house, it's not terribly expensive to calibrate calipers. I would caution though, that if you don't have any trained personnel in-house, you'll want to invest in assuring you set the lab up correctly.

If the calipers and micrometers have any potential impact on product quality or whether it will meet your claimed product specs, I would weigh carefully as to whether or not you want to take on that risk. In some situations, little details of the calibrations on micrometers can make a difference as to whether they make good readings or not. If you don't have adequately trained personnel, and the other needed things to calibrate them correctly, you will induce some potential risk by taking that on. There is good reason why manufacturer's have recommended calibration procedures and intervals on these things. So it is indeed important to calibrated them correctly to minimize risk. If there is any human safety risk potential in the products you manufacture (i.e.: automotive, medical, FAA, etc..), then think carefully before making the decision to do in-house.

posted 01 May 2001 04:39 PM               

As to what constitutes adequately trained personnel, there is not a really simple, easy answer. That depends on the complexity of the calibrations. I was ex-Navy, and had attended the calibration school at Lowry AFB, along with extensive Navy electronics training. I worked under others knowledgable in the field for many years. So as a complex package, it all added up to "adequate" training.

For someone starting fresh, you need some building blocks of training. There are a number of ways to accomplish it. The simplest would be to locate individual training courses for each instrument type you will support. Some of the manufacturers have courses in dimensional measurements (Mitutoyo has, I believe, courses held in the Chicago area, Charlotte NC area, and perhaps some other places). Their course is a few days long and covers the principals of dimensional measurements. This in itself would probably not be fully satisfactory. You will need some courses in general metrology, and perhaps some background (such as through ASQ) in Quality. There is a course through a calibration training provider in Minnesota on CD ROM. You could do something such as purchase those courses, and have tests proctored through your training department, and add those to the mix. Fluke has a course in basics of electrical measurements. Another area that I have found useful over the years is membership with NCSL (National Conference of Standards Laboratories) found at www.ncsl-hq.org . They have a lot of information on how to set up a calibration program, resources for training, etc.

Training should include specific certified training for equipment types you will calibrate, and courses in general metrology. It also makes some difference as to what level of quality system your company must maintain. If you are QS9000, FDA, USDA, FAA or NRC compliant (and possibly others), your calibration program must be a lot more stringent than if you don't need to comply.

Please feel free to email for more detailed questions.

posted 02 May 2001 01:39 PM            

That's a tough question to answer.

If this is the career path you choose, then I would recommend a degree in Metrology. There is so much involved in the running of
a calibration lab that you would be at a great dis-advantage if you took a lesser path.
Our lab was started in 1989 as a cost savings to the company. We didn't have to contend with ISO or QS back then, but we sure do now.
Everything changed in 1994 when the work was started to get QS certified. It was no picnic. But our company made it mandatory in
'89 to get a degree and I'm glad they did.
We still attend various seminars to keep us up to date on what's happening out there and I continue to visit this sight. The wealth of
information exchanged here is enormous and the people very helpful.Again, something not available back in '89.
As far as location, as long as you can document the temp/humidity levels are stable and within the limits you set, you can put the lab anywhere suitable for your company.

Of course, these are my opinions and I could be wrong, but I hope I was of some help.
Good luck and don't be afraid to ask for help along the way. That's what we're here for.

posted 06 June 2001 09:37 AM               

quote:

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Originally posted by Pamela Kaczmarczyk:
... Also, my company is looking at where to locate the calibration activities - the thought is putting it in library. Is this ok? We are looking at calibrating attribute gauges, micrometers, calipers, etc. Can anyone help me out ...

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Pamela,

The general considerations for a dimensional calibration lab include control of temperature, humidity, cleanliness, vibration and access. The library is probably better than the manufacturing floor, but you have to look at your measurement requirements to see if it is "good enough". For example:

• Can the temperature be controlled to 20 deg. C plus or minus one or two degrees?
  
• Can the relative humidity be controlled to between 20% and 50%?
  
• Is the air clean enough that dust, oil particles & etc. will not contaminate your measurments?
  
• Is the location far enough away from vibration sources so that the measurments are not affected?
  
• Can access be controlled, both to help control the environment and to ensure that only "authorized" people are in there?
  

NCSL has a recommended practice on calibration laboratory design -- see the contact information in a message from Jerry Eldred elsewhere in this thread.

posted 07 June 2001 08:01 PM            

Precision in our business is generally +/-.005 inch. My "lab" is an office shared by the Shop foreman, DNC computers, and CMM. It is air conditioned, but I haven't tried to control it to 20 deg. C +/-2 deg. We do calibrate to a set of tracable gage blocks which are checked every 36 months by an outside lab.

I calibrate Mics, calipers, verniers on the gage blocks. Some larger tools, protractors and fixtures are checked on the CMM which is calibrated once a year by an outside source.