Caliper Calibration - How to Calibrate a Caliper
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- เผยแพร่เมื่อ 1 มิ.ย. 2024
- In this episode, we’re going to talk about the how to calibrate calipers.
In past Mitutoyo Metrology Training Lab episodes, we have defined the concept of calibration, discussed the purpose of calibration, and introduced important aspects of what makes a good calibration method. In this episode, we will apply all those ideas to the calibration method for a caliper.
Calibration is a search for errors and we want to develop a calibration method that efficiently hunts down and finds any potential errors in the measuring instrument. So how do we best do that for a caliper? Well, there is a nice American National Standard for digital, dial, and vernier calipers, called ASME B89.1.14, and the calibration method we’ll be discussing is based on that standard.
#Mitutoyo #CaliperCalibration #Metrology - วิทยาศาสตร์และเทคโนโลยี
I working in automotive industry in standard room. We need calibration training. So what to do?
I do not work for or receive any compensation for my endorsement of this company. I have dealt with them for 30+ years and find them reputable and fair.
MILHARD SALES PVT. LTD.
i like how they just pinned this without replying xD
In Japan, Mitutoyo is pronounced Mitsutoyo, and is written that way in katakana on the Mitsutoyo website (ie ミツトヨ). The tu instead of tsu is a hang up from the romanization of Japanese in pre-war days. There is no such sound as tu in Japanese and never has been. The company was originally established as 三豊製作所 (Mitsutoyo seisakujo). Seisakujo (or seiksakusho) means something like factory, literally "things-make-place", so basically manufacturing. The characters 三豊 are also pronounced Mitoyo, and used as a place name. The Japanese website of Mitsutoyo has a history section, and states that the company started as a research institute in Kamata, Tokyo. There is no clue as to why the company was named Mitsutoyo. However, when the second character (toyo) is attached to a number, then it means something like "exceeding standard". So as 三 means three, then it is possible that the founder of the company in the 1930s wanted to express a high standard of quality for the products, and named the company thus. Toyo can also be interpreted as meaning abundant, rich.
Best wishes from Japan.
Jim was my instructor for the Mitutoyo Metrology Course that I attended at Mitutoyo's NA Headquarters. Having worked as a QA manager in Automotive/Aerospace for close to a decade now, I will say that Jim was one of the most informed people I have ever come across in this field. He not only has the technical knowledge but also understands the field from the practical perspective of those working on the floor of these shops. If you ever get the opportunity to attend any of Mitutoyo's courses I highly recommend it.
Thank you for the kind remarks Robert.
As you said about ASME b89.1.14, there is a table there containing the MPE values for checking and comparing our measurement errors like 'E'.
So if E is less than the MPE value, but not zero, must we add the value of the measured E to the next measurements we take when measuring???
The explanations given are for "verification of measurements between tolerance" and a "calibration" method in case the device is not between "tolerance " is missing or not possible to perform. What if the device doest not pass? What to do to bring it back to specification?
"It's not correct to rock it around to get the value you like..."
-Proceeds to rock and squeeze calipers until they read minus 5/10ths for every measurement-
A technician will almost always rock a caliper back and forth to allow the measuring faces to properly settle. I believe the video was trying to emphasize that a technician should not seek out a measurement result they prefer or like, but rather the correct measurement result.
11:34 Yep, keep pressing until the calipers show the value you expect
Really excellent video Jim!
Glad you enjoyed it!
You can always press harder to get different readings. Press the outside of the jaws themselves together, not the body with the electronics.
so by doing so much work to "calibrate", then tell me how exactly will be apply corrective action?
Light is one of the most accurate forms of measurement from what I've seen...
Thanks Jim.
Given your outside calibration data test points, what minimum measurement would you be comfortable declaring this caliper be used for and how would you back up that declaration? I will tell you from experience that when presented to modern medical device auditors, they will have issues with this caliper being used for measurements smaller than the lowest calibration point (1.0").
Jim, I also have searched the Mitutoyo website for a 0.2000" setting ring gage for the Inside knife check. I cannot find it on your website. Can you tell me where I can find this ring gage?
I had to special order a ceramic one, but the steel one is standard product, p/n 177-366. For some reason, it is not in our catalog, but it is currently available product. Thanks, Jim
How to check parallelism of measuring faces and how to reported value??
Where can you see how to use the adjusting screws to align the jaws parallelism ?
thanks Jim. Do we need to consider the uncertainty of the gauge blocks in the calibration?
It depends. Gauge blocks class x has an error so low that probably you wouldn't be able to read without the proper equipment. So the answer is: if you are using the proper equipment and your equipment it's calibrated. You shouldn't. If your equipment isn't calibrated you shouldn't use it to calibrate your calipers
So this may sound like a dumb question, but so if the calipers do not come within specification would they just be considered trash? Or is there a possible way to correct them
I have searched the Mitutoyo website for a 0.2000" setting ring gage for the Inside knife check. I cannot find it on your website. Can you tell me where I can find this ring gage?
I ordered a 0.2000 inch ring gage from a company in NY called Thread Check Ink.
How many correction Tolerance recomendation from Mitutoyo,?
I have a weird issue, I open the calliper fairly wide and then close it again, sometimes it goes back to zero and sometimes it isn't. Though I have noticed that if I take the number that it is off by on the zero point it is the correct mesurement. Any ideas what could be causing this?
faulty electronic components, seek replacement
The caliper readout is 0.005. The tolerance is 0.001. A measurement of 0.0012 will give a readout of 0.001. Is this still within tolerance? My documentation from mitutoyo says 0.02 mm 'round-off error not included'. And I don't understand why there is a difference between the metric and the imperial system. Accuracy of 0.0015 (or even 0.001 inch) and 0.02 mm is not the same. Is there a different ISO tolerance between them?
Im wondering this too.
Hi Jim where can i find a list of tolerances for calibrating different instruments?
did you ever figure this out? I'm looking for the same thing as well.
I'm also looking for the same... where can get exact list of Tolerance.??
Also looking for this, would be very grateful if someone could point me in the right direction 👍🏻
A bit late to the game, but you clearly state that the inside should be checked at a size of 3/4" minimum, and then check them at 0.5000"
Have a question about the tolerance you have on the result card. According to the B89 standered for "other measuring face" you are asked to use the Smpe or the scale shift. This is turn would make the tolerance +/-0.0020 for anything between 2 and 8 inches. You have the tolerance in the video at +/- 0.001. Am I missing something?
Thanks
Great vids and I plan on coming to Aurora for seminars soon...
You are correct on the tolerances. However, I'm measuring lengths less than 2 inches, so the +/- 0.001 inch tolerance applies.
Yes I see that now. I had a brain cramp. Thanks for a great series of vids!
Hello i would like to ask, its worth to do a calibration for a newly purchased Mitutoyo device/caliper? I mean for personal use, not in company/commercial use. Its worth to pay extra for calibration? Thanks
Thank you for your question. Whether your tools are calibrated and how often are decisions you must make based on the history of the tool and the risk involved. Are your tools used in harsh environments? Are they used throughout the day or only sparingly? What risk do you assume if the tool is out of tolerance? For those utilizing precision tools in commercial uses, calibration is a must because the product ‘has’ to be correct. The company reputation, and possibly lives of the customers, can be at stake. Regular calibration is a must.
How can I purchase the gages and data sheet shown?
Can you answer to me please. What calibration procedure did you use? Why not flatness? Thanks.
No! I don't wanna!
for doing this calibration, do we have to have a lab granite table?
yes and a space station.
You do not have to use a granite surface but you do need to use a calibrated surface of some kind in order to assess the step and depth of the caliper. You should not use a general purpose countertop as it has not been calibrated and is introducing uncertainty into the equation. You might consider something like an optical flat.
You can find a small calibrated granite surface for about 100 bucks or so.
how can you compute for the uncertainty if you are not going to take average of a number of readings?
I recommend you check out the ASME B89.1.14-2018 standard, as it includes an appendix on measurement uncertainty (for calibrating calipers).
How to reset the vernier
My Mitutoyo calipers are way out of spec, how do I get them fixed?
+ArmySigs
I do not work for or receive any compensation for my endorsement of this company. I have dealt with them for 20+ years and find them reputable and fair.
North Texas Precision Instruments
7464 Dogwood Park Dr. Fort Worth TX 76118
Phone (817) 589-0011 Toll Free (866) 589-0011 Fax (817) 590-0062
Email support@ntpi.biz
ArmySigs, you can contact Mitutoyo Repairs at 888-MITUTOYO or you can get additional by visiting our website at www.mitutoyo.com/support/repair-service/
What do you consider "way out of spec to be"? What be kind of work do you do with them, just curious.
First off check you gibb play,,your set screws probably backed out, set so it slids smooth but no up and down between the slides, reset your origin and check with a known round or block and compare, you als need to learn your calipers (feel). I found mine are spot on with a light touch.
I'm sorry, but this video does not show you how to calibrate the calipers. This just shows how to check the calibration. Now my calipers fail this check, so how do I adjust it to get it within specs?
I recognize there is some confusion with the definition of "calibration". Service or repair or adjustments (sometimes to improve accuracy) are typically part of the overall calibration process, but the essential calibration of most measuring equipment is to simply check the accuracy using reference standards. If the as-found calibration readings of a caliper show it to be out of tolerance, then addition service is needed. We plan to discuss service and repair in future episodes. For more information on the confusion surrounding the term calibration, check out th-cam.com/video/NV1VToAqfXI/w-d-xo.html Thanks, Jim
I don't understand why it is wrong to take the average of a bunch of measurements. I understand that an instrument that doesn't repeat within a certain tolerance shouldn't be used... But presumably a tolerance is always greater than zero, right? So we might still expect our measurements to have some variance, however small? And depending on the error distribution, the average of repeated measurements would contain some information about the measurement that could not be obtained as reliably from a single measurement, no? Doesn't the central limit theorem apply here?
what if it's not in tolerance, show how to make it back into tolerance, thank you
You'd need to either resurface or replace the measuring surfaces
There's no way to "repair" it by yourself. You'd have to get it sent to a machine shop where they can work on the surface.
@@jordantyo7839 nope. Actually there is. Done it myself on many calipers. Pretty easy actually.
@happy jack please explain how to do
yeah screw going to sleep, I had to learn about caliper calibration.
3:00 I've never seen a metrologist (or anyone) slam calipers together like this.
I use digital callipers everyday at my job making ceramic tile. Slamming them shut will very likely throw off the zeroing of the caliper. I agree with you.
There is no slamming at 3:00. Are you watching the same video I am?
@@nirv Regardless of the time in the video, the dude CLEARLY slams them in the video. If I did that at my job where I use them roughly 8 times a day mimimum, everyday, the measurements will be off easily by at least .005" if not more. Yes it matters in manufacturing.
@@markjones2349 Give a time stamp. I didn't watch the whole thing.
@@nirv No I'm sorry but I'm not gonna go watch the video for you because your lazy.
Am I the only one who has noticed this? For the inside measurement the calibration sheet said 1" and yet you measured 1/2" to get 0.4995"
Yeah.
I have the same calipers. When I turn them on it shows 167.56mm instead of 000.00. How can I set them to show zero's instead of 167.56mm? Thanks
Press and hold the origin button with the jaws closed.
What's the code number on your caliper? Please email Tech.Support@Mitutoyo.com
I dropped my calipers on the hardwood floors and now I'm afraid they might be off
Did you invent the steak?
I'm fascinated this process is not automated
People are always more important than robots .. a machinist needs to know what he's doing.. if your a U.S. Marine u always need to understand how a rifle works. U cannot rely upon smart bombs all the time.
Same thing here. Skilled labor is a learned apprenticeship type science. It's invaluable. It's always a Craftsman who makes precision things. Much more so than just an automated system... using calipers to measure your work is a good skill... And Mitutoyo is among the best.
I suppose in the vast majority of cases it's just less economical to design and build an automated process for it given how infrequently calipers need to be calibrated
For now 😂 lol.
I lost an inspection job opportunity because of this.
I have 35 yrs of quality and inspection on many jobs.
But, we outsource all our tools for calibration.
Large equipment used calibrated standards that are transferred to the big equipment.
This looks like basic stuff to me and anyone can be trained to do it.
I’m very confused by your comment, what exactly caused you to loose a job opportunity?
Most companies outsource speciality tool calibration, not because they cannot do it themselves, but because it looks & is more reputable to have a neutral party inspection.
@@scottp.548 that sounds like a bunch of fluff 🙄 There is nothing shady about a company performing in house calibration. Why on earth would you think less of a place that doesn’t send out for calibration? Why would they be considered less reputable?
Am I missing something? Did he just say that -0.0005 is minus five tenths?
Five tenths of a thousandth. Thousandths (Thou) is a common unit of measure for this level of precision. He goes over this at 9:26
This is machinist terminology: .001 is a “thou” .0001 is a “ten thousandth or simply tenth”.
Does anyone here know if the person doing the calibration needs to be certified? And if the certification is required, does he need to renew his certification after a certain period of time?
Edit: As an auditor (still learning), I am auditing my company's supplier. The supplier calibrates their calipers, micrometers and height gages internally instead of sending them to a certified calibration agency. The guy doing the calibration has the appropriate training and certification but dated way back in 2014. I've checked ASME B89-1-14-2018. No mention of this at all.
Heya! From my 15 years inspection experience from job shops to medical manufacturing you do not need to be certified to perform in-house calibrations; you just need to know what you’re doing lol
Performing monthly calibrations is usually part of the inspectors job and is totally normal. You just wanna make sure they’re using the proper masters/standards to do the calibrations. Unless the company is ISO certified, there really are no “rules” they need to adhere to (a majority of ISO is about the records you keep); most of the specs out there are kinda “suggestions” nowadays which can be unfortunate if left in the wrong hands.
I am curious as to what certification was provided to you for the guy you mentioned if you don’t mind sharing it? I like to refer to Inspection as an “old man job” since you basically learn everything from some old guy who’s been doing it for 40 years lol.
You shouldn’t be alarmed or concerned if they’re doing in-house calibrations; it’s just probably confusing and foreign to you if you’re not familiar with the process. If you have any specific questions please feel free to ask 👍
...i believe you meant 5 ten thousandths = .ooo5???????????
Resolution on caliper is .0005". Please veiw our online classes www.mitutoyo.com/on-demand/
In what universe does 0.0005 = five tenths?
isn't the first decimal place tenths? , doesn't it go 0.x = tenths , 0.0x = hundredths , 0.00x thousandths ?
looks like what you wrote, 0.000x is five millionths not five tenths
or is this some new fangled common core maths?
Hi Andrea, thank you for the question. Thou, which is short for Thousandths and ten thousandths would be shortened to tenth which are common units of measurement for this level of precision. So here, it is Five tenths (of a thousandth).
It's sad that after all these years this tool has all thee problems all related to human error and the way it is used. May be it should have a built in level or some capabilities for placement of the object being measured. If you were to measure some objects that you did not measure before and you had know prior knowledge of their size, your error would be larger. Now I know why My Hornady Caliper never gives me the same value no matter how many times I measure something. Therefore I give up hope for an exact measurement.
I think you might have unrealistic expectations about how small you would like your uncertainty to be. Everything in the world is uncertain, the only question is how uncertain.
I’m so high
Looks like you wiggled your way to a perfectly biased calibration. I will have to question any tool that relies on a human for calibration. There should be a mechanical test that can hold the caliper at the exa t angle and pressure every time. The way it's done here looks like you wiggle until you get what you feel should be right.
1:57 "Look silly" ?? Who are you talking to? Some hands in his pockets duffus? On what planet does holding something up to the light to see something "look silly"? I can't imagine what kind of do nothing, know nothing crowd you hang with to even think that.
Sniper tools
This is NOT calibration. This is inspection. You are making NO adjustments.
Yeah but how about showing how you actually CALIBRATE the calipers.
You bring up a great point. There is often confusion associated with the term "calibration". It can be used differently in across metrology. The video th-cam.com/video/NV1VToAqfXI/w-d-xo.html discusses this very topic.
CALIPRATION
Over all results is not a proper calibration. I think the hand tools do not work on this hand.
This isn't calibration. It's just checking that the existing calibration is within tolerance. There's no method for correcting any deviation except the obvious 'Buy a new caliper'.
You bring up a great point. There is often confusion associated with the term "calibration". It can be used differently across metrology. The video th-cam.com/video/NV1VToAqfXI/w-d-xo.html discusses this very topic.
You're NOT showing "how to" calibrate a caliper. You're just showing us a caliper that is within the tolerances of a standard.
Don't waste your time. This is NOT "How to calibrate a caliper". It should be called "How to test if your caliper needs calibration, but we won't tell you how to actually calibrate it"
Do you know if there is a video on TH-cam that shows you how to calibrate your calipers?
The calibration is held within the magnetic strip so there is no way of adjustment. Once they are bad that's it.
Exactly!!! Wasted my time.
Nope, what you're talking about is adjustment. If you want to adjust the instrument, you have to calibrate it first.
@@oogthecaveman Ah that makes sense. Thanks for the clarification.