[To...] Posted October 19, 2018 Share Posted October 19, 2018 I stand corrected. I have also verified this with a Zeiss service tech. They use their own probe when measuring the step block gauge. Link to comment Share on other sites More sharing options...
[To...] Posted February 6, 2019 Share Posted February 6, 2019 Please sign in to view this quote. You mean like this? . . . Link to comment Share on other sites More sharing options...
[Ro...] Posted February 7, 2019 Share Posted February 7, 2019 Please sign in to view this quote. But how do you get your sphere orientated on the plate? stand over it and look down? A single screw can constrain X&Y, but not rotation. Link to comment Share on other sites More sharing options...
[Me...] Posted February 7, 2019 Author Share Posted February 7, 2019 What if you are using a 30 mm and an 8 mm on each machine? how would that fit into this discussion? Link to comment Share on other sites More sharing options...
[Ro...] Posted February 7, 2019 Share Posted February 7, 2019 Please sign in to view this quote. Well how do you currently stage it? Link to comment Share on other sites More sharing options...
[Ro...] Posted February 8, 2019 Share Posted February 8, 2019 I have some old cad models for 8 & 30mm sphere storage, but it was rather bulky and i never finished development........Capture555.JPG Link to comment Share on other sites More sharing options...
[Ch...] Posted February 8, 2019 Share Posted February 8, 2019 I just learned this trick. You can have Calypso measure the exact angle if you have the right reference sphere. Did anyone else not know about this? Link to comment Share on other sites More sharing options...
[De...] Posted February 8, 2019 Share Posted February 8, 2019 Please sign in to view this quote. The 8mm sphere will not have been used during the calibration of the CMM so it cannot be included as having been calibrated when the machine was. The Reference Sphere that is 'paired' with the machine is considered calibrated because it was used during the calibration. The cmm / reference sphere / temperature sensors are calibrated as a system with each component interdependent with the other components of the system while checking a known length standard. This works because of the interdependency of the components. The 8mm sphere is not included in the calibration so is therefore not calibrated unless it is done separately. I do not know what the 'right' thing is to do, however the following is how we are currently dealing with it. We have the certification for the 8mm reference sphere and we have it in our calibration system with a very long interval. For use on the CMM we do the following. For our purposes we only need to use our 8mm sphere for the ability to do dynamic tensor calibrations for probes that are too short to otherwise reach the circumference of our 30mm ball. So we run a Dynamic tensor calibration on the 8mm sphere so that Calypso will be able to calculate the bend allowances for the stylus system. Once that is done we do a tensor-requalification which uses the main 30mm Reference Sphere and has the sphere coverage modified to a smaller angular segment so the probe will clear the sphere. This updates position data on the probe without clearing the bend allowances. Now our probe has bend allowances from the 8 mm sphere which should not be negatively impacted by any size error in the 8mm sphere, we have location and size information based on the 30mm sphere which is 'calibrated' with the machine. In this way our probes maintain traceability for size and location to the calibrated sphere and only bend allowances are coming from the 8mm sphere. If there is any question regarding the roundness of the probe tip at centerline due to the lmited sphere coverage, it can then be verified against the 8mm reference sphere which we have a cert for or alternatively can be chaecked against a high quality ring gage. Link to comment Share on other sites More sharing options...
[Je...] Posted February 9, 2019 Share Posted February 9, 2019 Please sign in to view this quote. News to me Link to comment Share on other sites More sharing options...
[Je...] Posted February 9, 2019 Share Posted February 9, 2019 Please sign in to view this quote. Put a second hole in the base for locating on your grid plate. Link to comment Share on other sites More sharing options...
[To...] Posted February 11, 2019 Share Posted February 11, 2019 Please sign in to view this quote. First, I take a straight edge and scribe pencil lines using the hole centers as a guide. Then, I mount the reference sphere, using the tick marks on the side of the base, lined up with pencil marks. I have to believe I am within a degree or two. Link to comment Share on other sites More sharing options...
[Ro...] Posted February 11, 2019 Share Posted February 11, 2019 Amateurs! 😃 Did you notice that the tick marks are unevenly spaced around the base? Link to comment Share on other sites More sharing options...
[To...] Posted February 11, 2019 Share Posted February 11, 2019 Please sign in to view this quote. No, I didn't 😮 😮 😮 Link to comment Share on other sites More sharing options...
[Ro...] Posted February 12, 2019 Share Posted February 12, 2019 I used to do the same thing, i even marked 1 notch with a paint marker.base1.jpg Link to comment Share on other sites More sharing options...
[Aa...] Posted May 28, 2021 Share Posted May 28, 2021 Please sign in to view this quote. I have yet to see a Ref Sphere Cal Cert with an uncertainty of less than 0.0003 mm. That said, I would have a hard time keeping up that poker face. I would have to fight the urge to laugh in their face. Link to comment Share on other sites More sharing options...
[An...] Posted May 29, 2021 Share Posted May 29, 2021 Please sign in to view this quote. See attached.Contribution_31_05_2021_1.pdf Link to comment Share on other sites More sharing options...
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