Subject: Uncertainty Debate RE33 Date: Tue, 2 Mar 1999 16:47:28 -0500 (EST) From: TSmith To: Greg Gogates Greetings Brian, Interesting read. You missed my point, I Read 1297 several years ago. Still a good read but If I have to restate the reason, I doubt It could be clear enough so, I move on. Good luck on the "Realistic Debate". -----Original Message----- From: Greg Gogates To: iso25@quality.org Date: Tuesday, March 02, 1999 1:33 PM Subject: Uncertainty Debate RE7 >Date: Thu, 25 Feb 1999 07:11:49 -0500 >From: "Brian S. Mulcahey" >To: Greg Gogates >Subject: RE: Uncertainty Debate RE4 > >Thank you Mr Nielsen, > I couldn't agree with you and Dr. Castrup more. The uncertainty budget does >play an important part of the calibration arena and it is still being >perceived as a hindrance possibly out of lack of information of its purpose. >Possibly it could be management's misinformation to the general personnel >and calibration tech's of it's function and need. Once the information and >understanding to management is there we need to mentor and help show the >role it plays in our customers needs and the calibration techs purpose. > Also we could use less of the anecdotal and more realistic debate / >decisions on this. > For Mr. Smith he requested some realistic examples, I would refer him to >the Singlas document that published numerous examples, the NIST TN 1297 has >some references, there is EAL-G17 on Coordinate Measuring Machine >Calibration, Y-12 from Martin Marietta Oak Ridge Plant on 1 D calculation of >CMM's. > As a Ex-Cal Tech /Assistant manager / manager / statistician apprentice in >a calibration facility and since going to Dr. Castrups initial train and >others each have provided valuable practical examples. The real question is >do you want to attend these seminars and receive these examples to put into >practical use. > The uncertainty needs of the lab was never a burden on the need of it, most >of the burden came from lack of time or organization of priorities. Those >outside influences of trying to calibrate, play Salesman, Assistant and at >one time Manager of a lab almost all at the same time was the real burden >that caused me to get out of the poor managed facility and go on my own. As >a previous user of uncertainty and continuing to assist other my experience >was the outside influences that hindered the process and not the task of >building a model and just doing it that was the problem. > There are numerous examples and technical bulletins from manufacturers or >you just need to request it from the engineer that was the developer on the >product. In most cases they will be happy to provide their notes for your >research and uncertainty process. I have found HP, Fluke and others >manufacturers of Physical / Dimensional equipment as well. > I look forward to continued realistic debate on this subject. > > >-----Original Message----- >From: owner-iso25@quality.org [mailto:owner-iso25@quality.org]On Behalf >Of Greg Gogates >Sent: Wednesday, February 24, 1999 10:07 AM >To: iso25@quality.org >Subject: Uncertainty Debate RE4 > > >Date: Wed, 24 Feb 1999 09:16:32 -0500 >From: Henrik Nielsen >To: Greg Gogates >Subject: RE: Uncertainty Debate > >Greetings, > >I agree with the points made by Howard Castrup. The fact that an uncertainty >budget cannot be developed by the average lab technician does not mean that >it is unnecessary or does not add value. > >In the attached contribution Jack Gale argues that because 95 % of the >people buying calibrations are not interested in uncertainty, it should not >be a requirement. I think you will find that the same 95 % would skip >calibration all together, was it not for some outside requirement (such as >ISO 9000) mandating they send their equipment to calibration on a regular >basis. > >I think we all have the basic, conceptual understanding that some >calibration is necessary and adds value. So we do think it makes sense that >instruments and standards should be calibrated on a regular basis. Up until >now we have based calibration requirements on rules of thumb that sometimes >makes us calibrate more than what is necessary, sometimes less than what is >necessary, but rarely, if ever, exactly what is necessary. > >Uncertainty budgeting is the only tool I know of that, used properly both by >the user of an instrument and by the laboratory calibrating it, can provide >a data-based set of calibration requrements, that will help us do the >correct amount of calibration to the appropriate uncertainty without making >it a question of faith or arbitrary rules of thumb. > >In most cases I have seen, the calibration requirements gets reduced (as in >less calibration), but more focused on what really matters for the >performance of the instrument or standard, when calibration requirements are >based on uncertainty budgets rather than faith in rules of thumb. In other >words, uncertainty budgets used appropriately saves you money. > >The fact that the average technician cannot design and manufacture a car or >an airplane or a computer without input from people with significant >theoretical education, does not make these products useless or less valuable >than chuck grinders. If we want progress and prosperity, we need to move >from anecdotal to data based decision making and in the world of >calibration, that means using uncertainty budgets to decide what needs >calibrating, how well and how often. > >Best regards, >Henrik S. Nielsen > >HN Metrology Consulting, Inc. >5230 Nob Lane >Indianapolis, IN 46226 >Phone and Fax: (317) 377 0378 >E-mail: hsnielsen@worldnet.att.net >Web: http://home.att.net/~hsnielsen > > >> -----Original Message----- >> From: owner-iso25@quality.org [mailto:owner-iso25@quality.org]On Behalf >> Of Greg Gogates >> Sent: Tuesday, February 23, 1999 8:17 PM >> To: iso25@quality.org >> Subject: Uncertainty Debate >> >> >> Date: Tue, 23 Feb 1999 18:02:49 -0500 >> From: Jack Gale >> To: Greg Gogates >> Subject: Uncertainty Debate >> >> To Greg, Bruce, Howard, et al : >> >> I'm leaning heavily towards the Bruce camp on this issue. We have over >> 1200 customers for our calibration service and only a handful could even >> begin to grasp the importance of uncertainties. We are dutifully >> marching towards G25 (many customers never heard of this either) and >> calculating the uncertainties for our standards. Maybe 2% of our >> customer base would appreciate it, even less would know what to do with >> the information. My customers represent a smart cross section of >> high-tech, biomed, nuclear and automotive companies, so let's not >> discount the source. >> >> Bold statement: "Ninety-five (SWAG) percent of the calibration dollars >> spent in this country are spent by people with no knowledge or interest >> in uncertainties." The metrology community knows, but the large base of >> users (who eventually pay all the bills) don't care. Based on the looks >> I get when G25 and uncertainties are brought up in discussion, I believe >> this to be true. >> >> We're attempting to sell filet mignon to a ground chuck customer base. >> Ground chuck is fine because most people are eating hamburgers. Let them >> eat chuck! It's nice that some people do filet mignon, Bentley >> automobiles and Armani suits, but burgers, Fords and Dockers do for the >> most of us. >> >> In the most real world (commercial), the customer would rather we spent >> our time to improve turnaround and pricing than uncertainty. This may >> seem as heresy to people with more academic pursuits in metrology, but a >> huge market exists for "tell me my equipment is okay for another year" >> and "get it back to me yesterday". >> >> I'm not saying no to uncertainty, just having it as the only choice. >> >> Historical Note : Early Ford Model T's were offered in many colors. It >> was only after improvements in the production line and the development >> of a fast drying black paint thet they were restricted to the single >> color. You may also note that GM caught up with Ford and passed them in >> the 1930's as the nation's leading auto producer because they offered >> what the customers wanted. Let's not repeat the past. >> >> >> -- >> ******************************************************************* >> Jack Gale, ASQ-CQE The opinions expressed >> ESSCO Calibration Lab herein are the author's and >> (800) 325 - 2201 do not reflect the opinion >> jackgale@esscolab.com of ESSCO Calibration Lab. >> ******************************************************************* >> > > >