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Measurement of tight tolerance features

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  • #51713

    Paula Dooling
    Participant

    The automotive industry is driving toward very small connector systems. With the small requirements comes measurement concerns on extremely tight tolerances.Β Β  I was wondering what type of measuremnt equipment would be able to measure of product with tolerances of +/-.01 with good GR&R results. Any ideas or advice would be welcome?

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    #180006

    Check out the Shadowgraph, it might take you down to 10 mics, I can’t remember the number.Below 10 mics you’ll need to use optical techniques. I’ve described some of these in an article called; Shape Repeatability, but I ought to warn you I don’t regard myself as a good communicator :-)Cheers,
    Andy

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    #180193

    Fontanilla
    Participant

    That’s funny!Β  I work in the automotive industry and we routinely measure (accurately and repeatably) down to .001mm using mechanical gages with electronic indicators.Β  Our gages are good down to .0001mm.Β  There are a great number of different probe configurations and electronic indicators from Federal Mahr and others.
    Don’t waste your time with optical methods unless your shape is very complicated.Β  They take too much time to use.Β  Instead, look in the Thomas Register for gage companies in southeast Michigan and you’ll find all you need.Β  Companies like Reef Tool & Gage, Southern Gage, Dependable Gage, Bower, Hanlo, Enmark, and the list goes on and on.
    And, you should think of this as your civic duty to the country.Β  As you know, Michigan is suffering the worst from the economic slowdown.Β  Your gage purchases from these excellent companies will help to stimulate the local, state, and national economies.
    Cheers!

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    #180194

    Dan,Please confirm you measure accurately and precisely down to 1 micron using a digital indicator.Also confirm your gauge has the capability of measuring accurately and precisely down to 0.1 micron.Regards,
    Andy

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    #180198

    Spencer
    Member

    1/10 inch is a very tight tolerance in the auto industry :-)

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    #180208

    Brian M
    Participant

    I doubt he was talking inches… and if he was, it would be 1/100 of an inch ;)

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    #180306

    Fontanilla
    Participant

    In fact, I’m at a machine run-off right now and am measuring to .001mm (1 micron).Β  We routinely hold tolerances in the sub-micron ranges.Β  Tolerancing gets tighter every year…

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    #180307

    I’m going to forward your post to colleagues in Japan: It’ll give them a good laugh!

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    #180311

    Fontanilla
    Participant

    Laugh all you want.Β  We do it.

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    #180312

    Dan,I apologize for my throw away comment. To claim you can measure to within 1 micron using the type of measurement system you mentioned is just ridiculous – especially when it seems obvious you’ve confused inches with mm. (Anyone can make a mistake – I do it all the time. What I try not to do is deceive myself.)Do yourself a favor, and your company, get yourself a set of traceable standards and check your measurements. It is not unknown for a salesman to dupe people by desensitizing the gauge – especially when it has an internal software calibration curve, and when someone is not experienced enough to know GR&R doesn’t check accuracy.If I’m wrong, others in the forum will correct me!Good luck,
    Andy

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    #180314

    GB
    Participant

    Andy,
    I agree with your comment and stance.Β Β  You can lead a horse to water…
    Dan, as Andy stated, you can not possible hold 1Micron of consistant measure with the scenario presented above.Β Β  I have a background in Military-grade optics and Spaceborne systems…1 Micron measures with mechanical gauges are not inherently reliable due to FOD.Β Β At 1M, dust, hair, lint, etc…seen, or unseen, will through your gauge off.Β Β 
    Don’t believe me?Β Β Β Β  Conduct a GR&R and pair it with an MSA against more reliable systems…Yea, verily, ye shall see the light (hint).

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    #180317

    BC
    Participant

    Ahh, acronyms.Β  A google search tells me that FOD means “foreign object debris”.
    In the auto industry, FOD also means “front of dash” or what used to be called the firewall (before the lawyers told us not to call it that any more).

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    #180319

    GB
    Participant

    FOD can be “Foriegn Object Debris”, or, “Foreign Object Damage”.

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    #180494

    Fontanilla
    Participant

    I know perfectly well the difference between .001mm and .001inches.Β  All you really smart people who think it can’t be done have never done it.Β  My GR&R’s come out to around 10-12%.
    What do you think the tolerance on most press-fit bearing bores is?Β  What do you think the tolerance on fuel injector nozzles is?Β  Power steering pump vanes?Β  If I have .006 milimeters total tolerance on a shaft diameter, how closely do you think I have to measure to be able to pass GR&R?Β  How do you think I do that?Β  In a lab?Β  No, on a production floor where I make thousands of these daily.
    Do yourself a favor and when a professional in the business tells you that it can be done, maybe check it out before you show your smallness.Β  Come out to the factory floor and see what we do.Β  You might just learn something.

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    #180503

    My advice to Paula remains the same:She won’t be able to measure down to 1 micron using any of the indicator devices you mentioned, whether it is on the shop floor, or in a Lab.

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    #180504

    Fontanilla
    Participant

    Only if she listens to your (bad) advice.

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    #180505

    Ron
    Member

    Dan,
    Β 
    0.010 is not considered a tightly toleranced measurement.Β  Typically as a rule of thumb your measuring equipment should be an order of magnitude tighter than the measurement you are seeking to measure, therefore use a gage that is accurate to 0.001 ths

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    #180509

    What about the other posters, do you think they’re wrong as well?

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    #180510

    GB
    Participant

    Going back and reading Dan’s orifginal thread.Β Β  He works in automotive.
    That alone, speaks volumes…

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    #180513

    Taylor
    Participant

    Dan Honey
    I spent more than my share amount of time building fuel injector nozzles, building air bag components building medical instruments, etc, etc etc, so I can say without a doubt your Gage R&R’s are wrong.
    Β 

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    #180516

    Hi Hbgb b^2,What distinguishes automotive? Why all the emphasis on ‘professional,’shop floor, and smart?Cheers,
    Andy

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    #180524

    GB
    Participant

    heh…The US Automotive industry is dying a prolonged and agonizingly slow death.Β Β  many attribute this latest fall toΒ a lack of common sense and willingness do “deign” themselves to what their Customers are demanding.Β Β  The big 3 continually froth at the mouth about how there product is as good/better than Toy/Hon…When asked for data, they all fall back on JD Powers surveys…bought and paid for by them.Β Β  All one need do is look at non-commercial rating sources for a glimpse at the reality.
    interesting sidebar…The TOY/HON plants in the US are seeing a marked drop in quality of late, when compared to heir flagships abroad.
    American ComapniesΒ can make good cars, the Big 3 simply fail to arm their folks and encourage them to do so.Β Β  Bailouts?Β Β  Hell no, let them drown in the morass of their own making.
    For the record, i drive an american Truck, as the Toys and Hondas can’t hold a candle to the F-150.Β Β Β My wife drives theΒ Japanese car because id on’t want her to break down with the kids…period.Β Β 

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    #180526

    Mike Carnell
    Participant

    Dan,
    I used to do some thin film plating a long time ago and measurement systems drove us nuts. I am curious what you are using specifically. If you prefer to answer on email I am at [email protected].
    Regards

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    #180530

    “Interesting sidebar…The TOY/HON plants in the US are seeing a marked drop in quality of late, when compared to heir flagships abroad.”I suspect we’re seeing the same over here too: I’ve had five of them, but the last one was difficult to get into first gear while rolling, and I’ve just had my first failure on my most recent purchase after only 40,000 miles.

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    #180562

    Fontanilla
    Participant

    Exactly my point!Β  .01mm is child’s play for measurement with even a mechanical indicator.Β  My original post was to say that Paula could use this means to measure and that optical means, etc. weren’t required.Β  I merely used the tighter tolerance and more precise measurements to state that we can do better than .01mm.
    .001mm is also achievable but does take more effort.Β  Yes, debris can throw your measurements.Β  You need to make sure parts are clean.Β  But, optical means aren’t required even at that level, depending on the product being measured.Β 
    The nay-sayers that claim this cannot be done have obviously never attempted nor seen it.Β  Were they to come into some of our plants, they would see it done every day.Β  Sadly (for them), they won’t get that opportunity.Β  Seeing is believing.Β  I speak from experience on what I see in production.

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    #180563

    Fontanilla
    Participant

    Chad darling, how can you say such a thing without any knowledge of the facts?Β  Opinion only?Β  That’s a shame.Β  Opinioneering is a poor substitute for actual data-driven knowledge of your subject matter.
    Surely if you’ve built soooo many precisely machined components, you must have had good GR&Rs.Β  Are you saying that you in fact didn’t have good GR&R and that you were “flying blind?”Β  I doubt it.Β  Maybe you meant to say that you, in your facilities, used different measurement systems to produce your fine products.
    I know GR&R, trust me.Β  I’ve been at it for quite some time.

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    #180564

    Fontanilla
    Participant

    Paula, see the following link for a starting point.
    http://www.mahrfederal.com/index.php?NodeID=8282

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    #180565

    Darth
    Participant

    “Chad darling”??? Looks like Stan has either taken on a new name or has found someone of similar proclivities.

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    #180566

    Nolan
    Participant

    Darth, there are more of them “coming out”. With more tolerance nowdays they are less concerned about the stygma.

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    #180569

    Yes, more tolerance can lead to Six Stigma :-)

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    #180572

    Paula,Don’t listen to this person’s metrology advice, but the following link is well worth a read. According to George Schuetz, Mahr Federal Inc: “This means it will be accurate to within five millionths (Β±0.000005 in.) of the certified size and will indicate the variation from nominal.”Ref: http://www.mahr.de/index.php?NodeID=13178How convenient – tune the gauge to the nominal size you want to measure .. I guess that is what one might call robust design.By the way, most other manufacturers specify 2 microns, but even George admits that what manufacturers specify can’t be achieved in the field – even when they use an anvil!!!!Take my advice – use an MSA to characterize your gauge using several traceable standards so you can be sure you understand the sensitivity of the measurement system.

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    #180582

    GB
    Participant

    “You know GR&R…”
    Hah!Β Β  You also “know” about accurate and precise 1M measurements by crude, mechanical means…
    Several tried to show you the way, but you remain steadfast in your ignorance.Β Β  Just because you use calipers/gauges that purport to demonstrate 1M accuracy, doesn’t mean you are able to hold that level of consistency in the real world.Β Β Β  This is about being called out in public on Quality-101 level topics.Β Β  Pride is a B****.
    Please clarify that you DON’T support Ford…Oh JEEBUS.
    Β 

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    #180658

    Fontanilla
    Participant

    Who said anything about calipers?Β  I use digital probes when measuring to that level.Β  The probes are good down to .0002mm.Β  Below that, you don’t get anything more.Β  And yes, I measured in a temperature controlled gage lab the first time I tried it.Β  First time, GRR came out to 147%!Β  Found an issue with flatness on the locating surface and corrected it and cleanliness.Β  Second time, GRR was only 78%.Β  Doing well, right?Β  50% reduction.Β  Found the reason was mostly within-part variation.Β  Clocked the parts and GRR dropped down to 8%.Β 
    Tolerance on this particular feature is .003mm.Β 
    Using a Pratt & Whitney gage (single probe and anvil setup) with a Sylvac 80 measurement display unit on it, repeatability of the probe was .00015mm.Β  Again, within-part variation was driver behind initial poor GRR.Β  Clocking the parts results in similar GRR at 8% but is much less sensitive to dirt due to the dirt grooves on the anvil.Β  We prefer the P&W.
    Too bad all of you nay-sayers don’t seem to know anything about this type of measurement.Β  You’d do well to open your eyes once in awhile and maybe learn something.Β  But I see you four guys are well acquainted with each other from your various responses on this forum over the years and seem to feed off of each other.Β  That’s too bad in that it seems to have limited your ability to grow.
    Well, I have better things to do, like finish running off my lathes, where I’m measuring bore diameters with Comptor gages, that have resolution to .002mm.Β  With .070mm tolerance, that’s more than enough.Β  My bore depth gages (custom height gages) read down to .001mm but accuracy is only .01mm.Β  That’s o.k. given my .200mm tolerance.
    Wish you could come and see it.Β  You’d think differently, I’m sure.Β  But no matter.Β  You guys go back to your, well, whatever close-minded things you do.Β  I’ll continue to make car parts, some of which go into “Big 3” cars, and some which go into Asian manufacturers’ vehicles.Β  They are pretty happy with the products.Β 

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    #180659

    Fontanilla
    Participant

    Nice that you’ve taken George’s words and added your own interpretation to them.Β  No where in that link is the word, “anvil” used.Β  That’s really great.Β  Twist the context to fit your view.Β  Really big of you.Β 
    Β You’ve also demonstrated you don’t know what a micron is.Β  .002mm (2 microns) Β = .000080″ (80 millionths).Β  NST standards are certified, per George, (and according to the documentation supplied with ours), to +/-.000005″ (5 millionths), which is .000127mm (or 1/10th of one micron).Β  We use a couple of these to show linearity of the gage plus have one for (near) nominal size, when the gage comes due for recertification.
    Β 

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    #180660

    I guess there is something wrong with your comprehension, as I wrote MOST OTHERS specify 2 microns – not George!!!! I wouldn’t believe anything George claims.

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    #180666

    You wrote: “Nice that you’ve taken George’s words and added your own interpretation to them. No where in that link is the word, “anvil” used. That’s really great. Twist the context to fit your view. Really big of you.”I didn’t want to answer this earlier because I wanted to check the site again to make sure someone hadn’t edited it – after all I don’t know who you really are. Try reading the entire site again!The fact that you don’t seem to acknowledge the use of anvils seems somewhat surprising. BTW sensitivity isn’t the same as linearity.

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    #180671

    Fontanilla
    Participant

    You really are showing how little a person you are.Β  “Read the entire site”??Β  Really.Β  You send a link to one page and then expect the reader to peruse the entire site to find your one reference.Β  The insinuation that I could have hacked the site and re-written the text is also quite insulting.Β  Grow up.
    And, maybe you’ve missed the posting where I did explain the use of anvils in our process.

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    #180674

    GB
    Participant

    Andy,
    His mind is made up.Β Β  You lead him to water…
    Laissez-Faire will take care of the rest.

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    #180688

    I agree …

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    #180730

    Fontanilla
    Participant

    In fact, it is you and Andy U who’ve been shown the water but instead, turned your noses upwards and walked away.Β  You’ve presented nothing to support your claims yet remain steadfast in your assumption that I am somehow wrong in my data and my processes.Β  I fail to understand how you two could be so stubborn in your refusal to accept that maybe, just maybe, there is a possibility that a mechanical gage can precisely and accurately and repeatablyΒ measure .001mm.Β  Considering that Andy doesn’t know how large a micron really is, distorts the writings of referenced individuals, and then denies the same of being worthy of reference, maybe I shouldn’t be surprised.Β 
    .01mm is easily measured with mechanical gages.Β  Take a Mitutoyo micrometer with resolution to .001mm and you’ll see it.Β  Use one with resolution to .0005mm and you’ll be even better but not quite able to measure microns.Β  Those devices are just examples of readily available store-bought instruments.Β  With proper fixturing and cleanliness, you can see down to .001mm.Β  Digital probes work quite well and aren’t susceptible to electrical noise.Β 
    Before you reply with some sort of smart-alec remark, do yourselves and anyone else who may be entertained by this exchange and check out SOLARTRON PROBE #DP/5/S WITH T-CON ASS’Y and METRONICS “GAGE CHEK” DISPLAY UNIT W/(8) DIGITAL INPUTS.Β  Do some research on this and report your findings here.

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    #180731

    Yes, I did miss your previous reference the use of an anvil. How small of me …As for the link – you provided it – I naturally assume you had read it, since it seems obvious the author had divided his subject into chapters.Since I believe this is an important topic to the automotive industry and any inflated claims about the performance of these devices may impact people’s jobs, I’ve decided to contact Mahr’s metrology department. I will certainly report back here.By the way, a micron is a micron unless you’re inching your way towards metrication!

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    #180737

    Chris Seider
    Participant

    Dan,
    A few questions/requests.
    1.Β  What specific instrument are you using?
    2.Β  What is the specification of the item you are measuring that uses this device?
    3.Β  Would you consider sending the gage R&R raw data to me at [email protected]Β Β  While I’m overseas presently, I’d take a look at the gage study.
    4.Β  Clarify to me….are you measuring with an instrument that has categories to 0.001 mm or 0.001 inch.
    I have no “skin” in the game and would be curious to understand the postings so I’m just wanting to look at the data.

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    #180881

    Fontanilla
    Participant

    Chris, I’ll contact you separately regarding your questions.Β  And yes, I measure on some gages to .001mm, not inches.Β  I’ve not measured in inches in years.

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    #180908

    Rick P.
    Member

    Dan
    Thanks for sticking with it.Β  An informative — but length reading– discussion was worth my time.
    One of the great concepts in Six Sigma (and probably in earlier quality initiatives) is the idea of bench marking.Β  Bench marking when examined objectivelyΒ gives a company an opportunity to improve their process.Β  Let me give an example.Β  A former company that I worked with gave lots of freedom to Six Sigma teams to address processing issues; we made electronic ceramics.Β  One team Β“Bench MarkedΒ” a bakeryΒ—yes those people that make yummy bread, and hot rolls; you got the idea.Β  With what they saw and learned that team improved the rolled throughput yield in their manufacturing process.Β 
    FYI:Β  I did a quick search based upon the information you provided and found the following specification for 971140-1 (DP/1/S).Β 
    Travel (2mm)Body Style (Straight)Accuracy (Β±0.24um)Resolution (0.12um)Protection (IP65)Power requirements (5 Β±0.25Vdc)Cable Length (2 meters) Β Β Β 
    Using interferometry based contact gauges, I can easily see a resolution of even less than 0.12 um = 1200 Angstroms.Β  Β Of course making these types of measurements in a production process has its own challenges and important questions involving parallelism, flatness, foreign objects, and so-on-and-so-forth have to be resolved to solve the measurement problem at hand
    I am confident that anyone that could Bench Mark your measurement process could learn a thing maybe even two.Β 

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    #180913

    GB
    Participant

    Your last paragraph proves the poin that several of us have been trying to make…Interferometry is called for to screen out false “correct” readings…Just because you think your gauge is telling you you have 1M resolution, doesn’t make it so…
    I wonder if Dan works for one of the Suppliers he listed in the original email…

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    #180915

    Taylor
    Participant

    Dont worry HB, sooner or later he will have that battle, then he will say: “I wonder if that is what they were talking about?”

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    #180932

    Dasare
    Participant

    I think you, Dan, Paula are one and the same person.

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    #180983

    Rick P
    Member

    Let me see the response to the following questions.
    (1)Β Β  What is a mechanical gage?Β Β How does a mechanical gauge work?Β 
    (2)Β Β  What is the difference between a vernier caliper and a digital caliper?Β 
    (3)Β Β  How is the mechanical motion of a digital caliper converted into an electronic read-out?Β 
    (4)Β Β  Is a digital caliper a mechanical gauge?
    Answering these questions will provide a giant leap in my understanding of what you are trying to prove or disprove Β– whichever it maybe.

    Β 

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    #180986

    Rick P
    Member

    I am neither Dan nor Paula.Β  With that said, let me add some additional thoughts
    Now that this discussion has traveled a tortuous path, let all of us go back and see the original question.
    Β 
    The Original Question by Paula Dooling:Β  Β“The automotive industry is driving toward very small connector systems. With the small requirements comes measurement concerns on extremely tight tolerances.Β Β  I was wondering what type of measurement equipment would be able to measure of product with tolerances of +/-.01 with good GR&R results. Any ideas or advice would be welcome?Β”
    Β 
    The automotive industry uses lots of plastics.Β  Some of which are very soft. Β I have found that obtaining a good GR&R on a soft plastic is not easy.Β  Making a good measurement to 0.001 inches using a mechanical gaugeΒ (for example a digital bore gauge)Β deforms the plastic which results in a large within part variation and a poor GR&R.Β  One quickly learns that selecting the correct gauge becomes very important. Β 
    Β 
    No one bothered to ask Paula what type of material was being measured! Β Let us not forget that there is a difference between the gauge and the part that is being measured.Β  The two (along with the operator) form a system and the results ofΒ the system measuremet is what the GR&R measures.
    Β 
    Β 

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    #181025

    Fontanilla
    Participant

    To quote your own posting of a few days ago (on a different topic), “You’re wrong.”
    Only I’ll provide some further explaination rather than just point out someone’s error and walk away…
    Interferometry is called for in certain situations.Β  We do use it here when measuring in the sub-micron level.Β  It works very well, particularly when measuring the profile of a surface.Β  It is very expensive!Β  I sincerely doubt Paula needs to use anything like that for her measurements, given that she wants to look at .01mm tolerancing.Β  It can be done, but it will cost her.
    I don’t “think” my gage tells me I have .001mm resolution.Β  I know based on the R&R studies performed on it.Β  Once again, I’ll make the statement that you and Stan and the others must have never used mechanical gages to measure to this level because we do it every day.Β  Obviously you think we don’t know what we’re doing but you know, if we were so wrong, our FTQ and warranty performance would quickly tells us.Β  Those two customer satisfaction indicators are either best in class or near it for most of our products.
    Here are some more references to check out.Β  We use their equipment daily in our plants.Β  Check out Marposs.Β  We’re holding some products to about .003mm using post-processing feedback from Marposs units.Β  Check out Heidenhain.Β  We use their glass scales in several gages to measure a lash setting on a bearing, which is required to be within .004 – .010 mm.Β  Yes, that is 4 to 10 microns.Β  Gage R&Rs to less than 10%.Β  Even the floor CMMs are certified down to about .0003mm although resolution on them is actually about .001 – .0015mm.Β  The gage room CMMs do a little better.
    Maybe you guys are just a little behind the times.Β  Maybe technology has passed you by.Β  Probably you need to dust yourselves off and get out there and take a look at what’s available and what you can do with it.

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    #181026

    Fontanilla
    Participant

    1) A “mechanical gage” is one that uses a mechanical mechanism to measure the sample, either directly or indirectly.Β  Often, mechanical gages include a fixture which securely positions the sample, and an indicator which touches the sample.Β  Indicators may be mechanical or electronic.Β  They may measure length, runout, roundness, diameter, etc.Β 
    2)Β A vernier caliper uses as series of lines scribe on a slide which the user uses to read the measurement of the sample by the position of those lines.Β  A digital caliper gives a digital reading of the sample.
    3)Β The mechanical motion of the digital caliper is converted using a number of techniques.Β  Most common is to use a small encoding device to convert the linear travel into pulses (counts) which are then converted to a digital measurement.
    4)Β  A digital caliper is a mechanical measurement device.

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    #181028

    Dillon
    Participant

    I work for an automotive company and we have no goods-in? We don’t audit any suppliers in their factories, who knows what they can achieve? You can claim anything you like, just send the paper work.

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    #181046

    GB
    Participant

    So, do you work for one of the firmsΒ you mentioned in your first post?

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    #181083

    Fontanilla
    Participant

    They work for me.Β  I discussed yours and Stan’s contention that .001mm isn’t possible without interferometry or other optical means with one of them yesterday.Β  He got a good laugh out of it.Β 

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    #181106

    Scott
    Member

    I have been busy too busy to see your response. Β Now, I am back.
    1.Β  Dan — I expected that you knew the answer to the question, “what is a mechanical gauge?”Β  I was hoping that some of the others would reveal their technical knowledge by answering that question.Β 
    2.Β  Based upon DanΒ’s description, I would broadly describe a mechanical gauge as tool that (A) make physical contact with the object and (2) the unit of measure is length. Β 
    3.Β  With this definition, the displacement of the gauge head (that makes physical contact with the object being measured) relative to its zero position may use a vernier scale, encoder (electrical or optical), or maybe interferometry.Β  With interferometry, I can easily see resolution of less than 0.001 mm if someone learns how to properly make a measurement.Β  Β Β Β 
    4.Β  Since know one replied to another posting that I made, I will repeat it below. Β I do this because it shows how easily a Six Sigma team can loose sight of the purpose of the Quality Improvement Project. Β Of course in a real team, the team leader and/or facilitator, which maybe the same person, would keep the project moving in the right direction.
    Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β  Repeated from Another Posting
    Β 
    Now that this discussion has traveled a tortuous path, let all of us go back and see the original question.
    Β 
    The Original Question by Paula Dooling:Β  Β“The automotive industry is driving toward very small connector systems. With the small requirements comes measurement concerns on extremely tight tolerances.Β Β  I was wondering what type of measurement equipment would be able to measure of product with tolerances of +/-.01 with good GR&R results. Any ideas or advice would be welcome?Β”
    Β 
    The automotive industry uses lots of plastics.Β  Some of which are very soft.Β  I have found that obtaining a good GR&R on a soft plastic is not easy.Β  Making a good measurement to 0.001 inches using a mechanical gaugeΒ (for example a digital bore gauge)Β deforms the plastic which results in a large within part variation and a poor GR&R.Β  One quickly learns that selecting the correct gauge becomes very important.Β 
    Β 
    No one bothered to ask Paula what type of material was being measured!Β  Let us not forget that there is a difference between the gauge and the part that is being measured.Β  The two (along with the operator) form a system and the results ofΒ the system measurement are what the GR&R measures.

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    #181115

    GB
    Participant

    Attention to detail, Dan…
    We never said it was impossible…We said that the variation inherent was to great to trust for reliable and repeatable consistency.
    Your supplier tells you that their wonder gauge can hold 1 Micron reliably…You try it and the gauge tells you you can, but it doesn’t mean it is really that capable.Β Β  Curious if you’ve compared to IF methods… as a test of your gauge.

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    #181157

    Scott
    Member

    You guys can laugh at the following statement — you made a mistake when you read my statement.Β 
    I said:Β  Using interferometry based contact gauges, I can easily see a resolution of even less than 0.12 um = 1200 Angstroms.”Β 
    Β 
    ByeΒ 
    Β 
    Β 

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    #181163

    Taguchi
    Member

    Fake Taguchi
    You need a doctor!

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    #181473

    Chris Seider
    Participant

    I’m doing Mardi Gras next week but still would like to see your gage studies.Β  I never received anything from you….
    [email protected]
    Cheers as they say over here!

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