[Cl...] Posted May 15, 2020 Share Posted May 15, 2020 I use formulas in result elements to output the stylus sigma and radius deviations. I've applied a ± 3 microns tolerance to the stylus radii. Is this too tight a tolerance? Many of them are failing for stylus radius. Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/ Share on other sites More sharing options...
[Er...] Posted May 15, 2020 Share Posted May 15, 2020 Do you set your nominal value to what the styli is purchased as. Like 1.5mm? The probe many times isn't is 1.5, so one or two microns can be eaten by that. We have quite a lot of special ordered probe sizes, and when they are used as gauge balls, we need to order like 10 to find 1 or 2 usable. Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-82970 Share on other sites More sharing options...
[Cl...] Posted May 15, 2020 Author Share Posted May 15, 2020 Please sign in to view this quote. Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-82972 Share on other sites More sharing options...
[Is...] Posted May 16, 2020 Share Posted May 16, 2020 Consider that the radius value from the CMM qualification could be affected by the Quality of the probe (too much glue, material of the stem, number of connections, etc.) other common problems are when the qualification doesn’t touch wear areas or ignore that the Sigma / radius value doesn’t represent with accuracy the wear in the probe. When the probe ball diameter is used as guage this is even more significant. I would say that tolerances and type of probe verification depends from every kind of inspection.Accessories -Stylus-Systems.pdf Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-82974 Share on other sites More sharing options...
[SH...] Posted May 16, 2020 Share Posted May 16, 2020 Please sign in to view this quote. 3 micron is too high, I think your probes are very old. Usually I get within 1 micron. Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-82976 Share on other sites More sharing options...
[SH...] Posted May 17, 2020 Share Posted May 17, 2020 Please sign in to view this quote. In thermofitpro I can fix the probe in any angle??IMG_20200517_155806.jpg Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-82978 Share on other sites More sharing options...
[Is...] Posted May 17, 2020 Share Posted May 17, 2020 Please sign in to view this quote. Thermofit is the material of the stem; actually there are some adapters to adjust your probes in any angle but these solutions don’t have the best accuracy, if your tolerances are tight, I would recommend them as something interim. When your custom design configuration is decided, Zeiss can quote an optimum solution with fixed or less parts (improving the qualification accuracy).. I think most of times the cost / quality is competitive. Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-82980 Share on other sites More sharing options...
[SH...] Posted May 17, 2020 Share Posted May 17, 2020 Please sign in to view this quote. I don't think zeiss will send to 2 or 1 micron eaten probe. Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-82982 Share on other sites More sharing options...
[Is...] Posted May 17, 2020 Share Posted May 17, 2020 Please sign in to view this quote. Depends of the ball grade, the 25 could have a diameter deviation of 0.0025mm (big spheres are more difficult to manufacture). 1 Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-82984 Share on other sites More sharing options...
[Er...] Posted May 17, 2020 Share Posted May 17, 2020 Please sign in to view this quote. If I remember correct Zeiss use Grade 5 as standard. (?) So I guess I sould have said up to 0.0013 based on Rodriguez chart. I cant figure out if your reply is a question, statement or your personal opinion? Anyway, the whole point was to shed light on a potential issue here. Setting nominal to 1.5 (as an example) with a tolerance of 0.003, when the probe infact might be 1.4987. But I can't answer if its a to tight tolerance. I have no clue how Clarkes stylus system looks like, material, lengths, number of joints, sensor, etc. So I tried to give atleast some relevant info to consider. Instead of claiming that 3 microns is too high and say what I achieve . Because its totally irrelevant and doesnt help him at all. 😃 Clarke try to see how well the stylus radius repeat when you qualify it several times. If it repeats good, then set the median value as your nominal. Then you also know how good it repeats, base your tolerance on that. Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-82986 Share on other sites More sharing options...
[Is...] Posted May 18, 2020 Share Posted May 18, 2020 The grade ball is not the same in all probes, with other suppliers this info is in their catalogs, and is common to see probes from grade 5 to 50.. Unfortunately, the grade only classifies the quality of the ball. If you have access to a high precision instrument (like a mahr ULM with good traceability methods) is easier to determinate a calibrated value for the sphere. If the qualification value in the CMM is different maybe there is a problem in the construction of the probe. Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-82988 Share on other sites More sharing options...
[Is...] Posted May 18, 2020 Share Posted May 18, 2020 … or wear in the probe: Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-82990 Share on other sites More sharing options...
[Er...] Posted May 18, 2020 Share Posted May 18, 2020 According to this, there is no difference in "grade" based on size. Only material. Where Diamong is "grade" 10, Diamond coated (up to 10mm) and ruby is "grade" 5. They only mention limitations in roundness for Diamond and Diamond coated, so it sounds like ruby are "grade" 5, unless you order "grade" 3. Do you have any documentation showing "grades" upon size? (I'm asking since Im intrested 🙂) Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-82992 Share on other sites More sharing options...
[Is...] Posted May 18, 2020 Share Posted May 18, 2020 Please sign in to view this quote. Looks like Zeiss only takes the grading for the roundness in that file… However searching ball bearing you find some tables with diameter tolerances: https://en.wikipedia.org/wiki/Ball_%28bearing%29 Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-82994 Share on other sites More sharing options...
[Is...] Posted May 18, 2020 Share Posted May 18, 2020 Please sign in to view this quote. The ZEISS brochure has some finger errors, the roundness deviations should be in nm not in um: Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-82996 Share on other sites More sharing options...
[Cl...] Posted May 18, 2020 Author Share Posted May 18, 2020 RDS/XXT/TL1 I use several straight stylus ranging from 0.3mm x 20 up to 3.0mm x 125 and a few star probes using 0.5mm to 2.0mm. I'm going with the ± 0.0013. So far none of my styli are out of tolerance. Thanks for the info fellas. Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-82998 Share on other sites More sharing options...
[Ri...] Posted May 19, 2020 Share Posted May 19, 2020 The diamond styli will not be made to perfect size like the other materials are. I had purchased some 3mm before, and they were 10-15µm off on the radius. I was told that this is common due to difficulty in machining the diamond. Made sense to me. Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-83000 Share on other sites More sharing options...
[Cl...] Posted May 19, 2020 Author Share Posted May 19, 2020 Are the diamond styli typically used for special types of material, or general use? Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-83002 Share on other sites More sharing options...
[Ri...] Posted May 19, 2020 Share Posted May 19, 2020 Please sign in to view this quote. I would say it varies. I purchased them because we were 100% sorting parts 24/7 on a DuraMax that was going through probes every few weeks. It is common to use them when measuring ceramic parts that are extremely rough as well. Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-83004 Share on other sites More sharing options...
[Is...] Posted May 20, 2020 Share Posted May 20, 2020 Please sign in to view this quote. Actually, is clearly defined in the catalog: Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-83006 Share on other sites More sharing options...
[SH...] Posted May 23, 2020 Share Posted May 23, 2020 Please sign in to view this quote. This is calibration result or you created a program by creating reference sphere as a feature?. What does point rigidity realy means in calypso?. Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-83008 Share on other sites More sharing options...
[Is...] Posted May 24, 2020 Share Posted May 24, 2020 Please sign in to view this quote. it’s a program scanning on the reference sphere (if you do it be aware that you could catch and misunderstand some limitations of the scanning and qualification). The rigidity is related to how much the probe flex during the touch, a bigger value is better. Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-83010 Share on other sites More sharing options...
[SH...] Posted May 24, 2020 Share Posted May 24, 2020 Please sign in to view this quote. Are you working according to ISO standards? what formula used in calculate the point rigidity?.I would like to know more about it that's why asking..IMG_20200524_180402.jpg Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-83012 Share on other sites More sharing options...
[Is...] Posted May 24, 2020 Share Posted May 24, 2020 Please sign in to view this quote. nop, the purpose of our graphics is detect potential issues in the probe (like wear).. We don’t calculate the rigidity, it comes from the CMM probe qualification: in case of scanning error, I prefer to use: RONt from the machine specs and use it as a constant for uncertainty estimation (Normally is 0.8um for a Prismo). Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-83014 Share on other sites More sharing options...
[Tr...] Posted June 24, 2020 Share Posted June 24, 2020 Please sign in to view this quote. Ive been looking for this formula as I could not get it to compute correctly, what was the code you entered in the results element? Link to comment https://qualityforum.zeiss.com/topic/15394-stylus-radius-tolerance/#findComment-83016 Share on other sites More sharing options...
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