posted 30 August 2000 04:53 AM            

At the moment there is a discussing about which measuring instruments ought to be calibrated and which not.
The head of our assembly department states that the instruments used in his department are only used to ãcompareä two parts with each other (to see if they fit), and therefore should not be calibrated.
On the other hand, the instruments used in our workshop (we also produce our own parts) are used to check the dimensions of a part in production against the one mentioned on its drawing. So, these instruments should definitely be calibrated.
Could you please give me your opinion ?

Also, would it be profitable to do the calibrations in-house ?
Can anyone give an estimate of the costs involved (we have approximately 1500 instruments in use) ?

posted 30 August 2000 10:24 AM               

As for the cost to calibrate, that is a complicated question. If you only have calipers and micrometers, you may find it is not too costly. But if you have many different types of instruments, you will have to do a cost evaluation. There are a number of factors to be considered. You will need a properly trained person to do the calibrations. You will need a written policy and written procedures. You will need proper equipment to do the calibrations, and need to maintain proper externally done calibrations on all of those. If your instruments are pretty simple, all of the above is probably pretty simple, and not too costly. If you have many highly accurate instruments that measure many different types of parameters, it may be questionable as to whether you choose to calibrate in-house. If you can post a set of how many, and what type instruments you have, I can give you a little better idea as to whether or not to calibrate.

posted 30 August 2000 03:12 PM               

TECHNICALLY they aren't "CALIBRATED" to a standard - identified - entered into the report history records - but each are evaluated and verified to our internally set tolerance ranges prior to being used.

posted 03 September 2000 07:13 PM              

Reasonabl insurance, if done in the most efficient manner. Costly, if not.

posted 06 September 2000 08:52 AM            

We are seeking T&E Certification and would like your interpretation on our requirements for calibration.

Presently we are tagging / id'ing all employee owned tooling as "reference only" and only calibrating company owned tooling. We are trying to establish intervals for calibrating tooling.

Presently I have no way of knowing when / where any tool is used as there is no traceability to any prints / machines that we build to any tooling used to verify measurements, other than my CMM machines.

posted 06 September 2000 09:54 AM            

Jerry, to answer your first question, the company is ISO9001.
As for the different types of instruments, I will try to give you an estimate of what we have:
+/- 100 clock gages (external, internal, depth), +/- 500 micrometers (of all sorts: inside, outside, depth, 2-points, 3-points, digital, with build-in clock gage, blade, thickness, screw thread, tubular inside, disc), +/- 350 calipers (of all sorts: analog, digital, inside, depth), 2 surface plates, 41 pocket test indicators, +/- 20 gage block sets, 15 height gages, 25 graphometers, 12 torque wrenches, and some other instruments of which I donât know the proper translation.

Two years ago, we send away a part of our instruments to a general calibration service. Using the cost of this calibration as a basis, we estimate the overall cost to calibrate all of our instruments at about $33,000 US.
Since we do not have any calibration equipment, or the personnel to do the calibrations, we wonder if it would be worth trying in-house calibration.

posted 07 September 2000 08:39 PM               

Louie - Yes, I agree that is too loose. There should be little differentiation between company owned and personally owned measuring instruments. If they can easily be interchangably used, it is dangerous territory to leave one uncal'd and the other cal'd/. As above with Martine, more detail next week.

posted 08 September 2000 09:05 AM               

quote:

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Originally posted by louie:

We are trying to establish intervals for calibrating tooling.

Presently I have no way of knowing when / where any tool is used as there is no traceability to any prints / machines that we build to any tooling used to verify measurements, other than my CMM machines.

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