The Elsmar Cove Business Standards Discussion Forums More Free Files Forum Discussion Thread Post Attachments Listing Elsmar Cove Discussion Forums Main Page
Welcome to what was The Original Cayman Cove Forums!
This thread is carried over and continued in the Current Elsmar Cove Forums

Search the Elsmar Cove!

Wooden Line
This is a "Frozen" Legacy Forum.
Most links on this page do NOT work.
Discussions since 2001 are HERE

Owl Line
The New Elsmar Cove Forums   The New Elsmar Cove Forums
  Measurement, Test and Calibration
  Tape Measure Calibration ?

Post New Topic  Post A Reply
profile | register | preferences | faq | search

UBBFriend: Email This Page to Someone! next newest topic | next oldest topic
Author Topic:   Tape Measure Calibration ?
louie
Forum Contributor

Posts: 19
From:Rochester Hills, MI
Registered: Feb 2000

posted 22 March 2000 05:48 PM     Click Here to See the Profile for louie     Edit/Delete Message   Reply w/Quote
Recently had pre-assessment audit and auditor says we must calibrate our tape measures as they are used as an in process inspection tool to measure length of material. The measurements we take are not critical measurements. If a piece is to be 6 " long, we have no tolerance to check to....

BUT the person 'calibrating' the tape measures does not need any formal training... just check the tape measure for deterioration and measure a calibrated block to see if it measures the same. When asked if I had to do nominals, was told no, just pick a length and check that. no difference on length to check no matter what the length of the tape measure?

Any one else have history with tape measure calibration?

Thanks

IP: Logged

pdboilermaker
Forum Contributor

Posts: 59
From:Russiaville, Indiana, USA
Registered: Apr 99

posted 22 March 2000 09:44 PM     Click Here to See the Profile for pdboilermaker   Click Here to Email pdboilermaker     Edit/Delete Message   Reply w/Quote
We use hard 160mm scales to measure stitch length. These were "calibrated". Our instructions are written somewhat like this.
1. Get in new scale
2. Measure gauge blocks to confirm accuracy
3. Put on calibration sticker
4. Check scale visually every 90 days for things like bent, broken, numbers worn off.
5. New calibration sticker

I know, I know lame as can be but it works when you come across an anal non pragmatic auditor.

IP: Logged

Jerry Eldred
Forum Wizard

Posts: 136
From:
Registered: Dec 1999

posted 23 March 2000 10:22 AM     Click Here to See the Profile for Jerry Eldred   Click Here to Email Jerry Eldred     Edit/Delete Message   Reply w/Quote
I am probably somewhere halfway between being a non-pragmatic auditor, and a practical type, as I have many years in calibration/metrology, and also some background in QS9000/ISO9000 and other quality systems auditing. So take my answer from that context.

From a quality systems perspective, it sounds like you have an ambiuguous requirement in your quality system.

You require the lengths of material to be checked (implying that you do care about length), and yet there is not an allowable pass fail criteria. It seems there needs to be a management decision as to whether they want to apply some pass/fail criteria (i.e.: if you measure what is supposed to be six inches, how much deviation is allowable?)

I am not in your process, so I don't understand what the spec truly ought to be. But in my humble opinion, I would suggest that you set some pass/fail limits on your measurements, make that your tolerance. If you already have gauge blocks, no further investment needed. But another method, depending on what tolerance you decide to certify your tape measure to (I recommend about ten times tighter than whatever spec you assign to your pass/fail criteria for the process measurement), would be to get about a 36 inch straightedge ruler (metrology grade) from one of the good dimensional instrument manufacturers. Use that as your standard. The manhours to check a tape measure would be less.

The other question that comes to mind is... is the measurement you make a deliverable? That is, do you measure to be sure a correct amount of material or whatever is supplied to the customer that you agreed to provide, based on that measurement? If that is the case, then you most definitely need to calibrate. But if, on the other hand, that measurement is only a 'convenience' measurement that does not have any impact on product quality in any way (including providing a dimension agreed to provide to the customer), then I would recommend not calibrating. But by al means, document those details, and place a NO CALIBRATION REQUIRED label on each and every tape measure. You can buy those labels quite cheaply from companies such as Brady labels.

It does come back to that age old question as to whether or not to calibrate. Calibrate if the measured parameter assures you provide something quantitative to your customer, or if there is safety or reliability or quality of the product based on that cal. Don't cal if none of the above are impacted by the measurement.

Hope I have been of help.

------------------

IP: Logged

Sam
Forum Contributor

Posts: 244
From:
Registered: Sep 1999

posted 23 March 2000 12:38 PM     Click Here to See the Profile for Sam   Click Here to Email Sam     Edit/Delete Message   Reply w/Quote
Our primary measuring device in use on the floor is the 16' tape measure. We were also requested to present evidence of calibration based on results of our pre-assessment audit. I purchased a "starrett" 16' tape with a long form cert., I then compare the two and record the results. Our tolerance is 1/8".
I was also asked for a MSA on the tapes. That too was enlightning; No two people could come up with a reading close enough to record. After lessons in the proper use of the tape I was able to put together a presentable MSA.
Lesson Learned; Make every attempt to comply with the requirement, it may be beneficial.

IP: Logged

Marc Smith
Cheech Wizard

Posts: 4119
From:West Chester, OH, USA
Registered:

posted 30 March 2000 02:09 AM     Click Here to See the Profile for Marc Smith   Click Here to Email Marc Smith     Edit/Delete Message   Reply w/Quote
Also see:
https://elsmar.com/ubb/Forum4/HTML/000083.html

IP: Logged

All times are Eastern Standard Time (USA)

next newest topic | next oldest topic

Administrative Options: Close Topic | Archive/Move | Delete Topic
Post New Topic  Post A Reply Hop to:

Contact Us | The Elsmar Cove Home Page

Your Input Into These Forums Is Appreciated! Thanks!


Main Site Search
Y'All Come Back Now, Ya Hear?
Powered by FreeBSD!Made With A Mac!Powered by Apache!