Tool calibration

It's not necessary, but I thought it'd be nice to have calibrated tools for the job I'm doing right now. So just for fun, I requested prices from my local calibration lab for calibrating my OD and ID micrometers and associated standards. I about wet myself when I saw the price list they provided.

$115 ea. for 0-1", 1-2", and 2-3" OD mics and $40 for each standard!

Dang, for that price I can buy a 0-1" mic with a long form certification right from the manufacturer.

Now, a couple years back, I sent some mics and standards to a 17025 accredited lab in Fort Wayne, IN and I know for a fact that the total bill, including shipping, was less than $120.

This local lab is based at, and does all the calibrations for our local Nuke plant and is trying to diversify. With these prices I don't see how they could compete with the regional labs here in the Northwest.

I'm interested to find out how much calibrations cost in your area. (Something simple like a 0-1" mic.)

Goes to show your have to shop around even for tool calibration. Much depends on the work you are doing. If your customers require you to maintain a top of the mark calibration program for your dull precision tool inventory, your fixed costs should reflect this and it should be declared as a cost center in your detailed responses to fully documented RFQ's. There's calibration programs and there's calibration programs.

Often it's enough to maintain a set of jo blocks and measuring wires and all your recorded data can be traced to them as your in-house reference standards.

As I understand it, how you set up your in-house QA is pretty much up to you so long as it conforms to ISO 900X, Gov't standards, or whatever, your documentation is up to snuff, and your people are trained in it and fulfill the requirements.

Long lines of ducks in a row are a sad fact of today's QA.

Have you considered sending them back to the mfr for (re)certification? They might be a bit more reasonable.

Hesstool,

The numbers you quote are indeed eye-popping. New Starrett or Mitutoyo 0-1s can be purchased on sale for that much.

Why not use a set of good calibration standard gage blocks (you should check stuff every day, anyway, right? ). I just bought a set of Mitutoyo calibration gage blocks for $35 bucks - they look new.

I guess that you could use pin gages (to test different spots on the face of the anvil/spindle more easily - at least that's what Meyer claims), and optical flats (to test for uneven anvil/spindle wear.

But if you check your calibration against a known-good standard every morning anyway, and the job doesn't need calibration certification, that kind of money surely would discourage me from having it done.

Best,

Jim

regular calibration labs charge much less than those figures for hand tool calibration.

I'm talking $12-25 for a caliper/micrometer, upwards of $75 for a pitch micrometer set. I'm guessing at my memory here. No big sticker shock, though.

Those mic standards that are a rod with lapped ends are not even very accurate. The tolerance on those lengths is something like +/- .0001".

Personally, I would get a set of jo-blocks from Enco or J&L sales flyers in grade AS-1 for $200. 81 piece, so you can stack up inside and outside dimensions, check micrometers at quarters of rotation to look for parallelism error (you will see it).

I'd also start off with brand new Mitutoyo economy mics. No spindle lock or friction thimble, but they calibrate just as good as all Mitutoyo mics, which is very very good.

Don't ever buy Brown & Sharpe Econoline micrometers. Chuan brand sets for 8% of the price are actually -BETTER-.

the difference here is
do you "know" it's good
and can you "prove" it's good

the cost of keeping those traceability
standards up is outrageous

to check your .0005 device they need a .00005 device traceable to dirt

to check our in house stuff we got some sort of $15k super mic

yearly papers on that piece of crap are a fortune

happy measuring

The expensive calibration services check all the (five or seven, I forget) different ways the mic can be out, and then provides a true "worst case" number.

Checking something that thoroughly is time-intensive.

It's exactly analogous to the difference between a diagonal step test on a milling machine versus testing each axis individually for accuracy. Much better idea of what is going on individual axis tests, but you don't get the best picture of what is really going on.

Any guestimates as to how expensive it would be to calibrate a Pratt & Whitney Supermicrometer Model B

Spud, my WAG is $7600.

I guess the point of my post was one of astonishment. I wouldn't doubt that the management at this nuke plant told the metrology lab to try and get some business "off the street". Why else would they try to get outside work when they've been operating off government money for it's lifetime?

I'm more than happy to send my instruments somewhere and pay $30 to calibrate them, but $115 is ludicrous.

I have been (very slowly) working on a ISO compliant quality system for my shop, but what's funny is that around here, nuclear is king, so most everyone who has a system in place is NQA-1 certified or compliant.

LAWTZ!! That's a SUPER mic all right.

All the certification forms show is that the mic is accurate if calibrated correctly.

If you have an ISO certified job shop nearby that does calibrations, this may work. May cost a bit, but they are very close, have the gear, have the stickers and the certifications that show they can calibrate mics and indicators.