[To...] Posted January 29, 2021 Author Share Posted January 29, 2021 Please sign in to view this quote. Interesting but I am not yet convinced. 😃 I understand why B simulator needs to translate but why does it need to rotate? Is your interpretation based on any documented set of rules? Using the orientation shown in your presentation, if we were building a Base Alignment, we would use the Datum A cylinder as the Spatial Rotation and it would control translation along X and Y and rotation about the X and Y axes. Next, we would use the Datum B cylinder (and for simplicity, I will use 1 cylinder along the X axis) for the Planar Rotation, it would control translation along the Z axis and rotation about the Z axis. If we looked at the Datum B cylinder actuals, we would see the Y location may not be at zero but the rotation angle about Z be zero, thus controlling the angle of the X axis. I will have to do some testing in Calypso to see what happens. Link to comment Share on other sites More sharing options...
[An...] Posted January 30, 2021 Share Posted January 30, 2021 _ Link to comment Share on other sites More sharing options...
[An...] Posted January 30, 2021 Share Posted January 30, 2021 _ Link to comment Share on other sites More sharing options...
[To...] Posted January 30, 2021 Author Share Posted January 30, 2021 I created 2 Profile characteristics on a freeform surface. One used A and B as Primary and Secondary and one adding C as the Tertiary with no change in the results. I also tested this on a cylinder but could not get an result using A & B only. When I repeated A or B in the Tertiary field, I got the same result as the Profile with ABC. Andreas, I don't believe the rotation of the Datum B simulator is correct or necessary due to the rotation about A. I do feel the translation of B is correct.Screenshot 2021-01-30 123220.jpgScreenshot 2021-01-30 123010.jpg Link to comment Share on other sites More sharing options...
[SH...] Posted January 31, 2021 Share Posted January 31, 2021 Please sign in to view this quote. Parallel cylinder?? What version 6.8? Link to comment Share on other sites More sharing options...
[An...] Posted February 1, 2021 Share Posted February 1, 2021 _ Link to comment Share on other sites More sharing options...
[Ch...] Posted February 1, 2021 Share Posted February 1, 2021 I saw parallel cylinder in Calypso 2020. I think it just best fits 2 cylinders and let you select a few options for the construction. We are still on 6.4.2803 but I need it to view and open newer programs as well. But to add some useful info : If the DRF is not clear enough that a few people can come to an agreement, I would suggest contacting design for their intent. Good luck. Link to comment Share on other sites More sharing options...
[Ri...] Posted February 1, 2021 Share Posted February 1, 2021 Tom, You cannot do it from the Characteristic side. You will have to create a secondary alignment and apply the correct buildup. Datum C will control the Planar Rotation. If you build the DRF inside of the Profile, it will build according to the Can/May/Must rule. Link to comment Share on other sites More sharing options...
[To...] Posted February 1, 2021 Author Share Posted February 1, 2021 Please sign in to view this quote. I don't have an issue with that. I'm looking for a valid argument, using the standards, as to why it should be interpreted another way. Link to comment Share on other sites More sharing options...
[Ri...] Posted February 1, 2021 Share Posted February 1, 2021 If I'm reading and understanding this correctly, they would have to specify which degrees of freedom the Datums control if they intended for B to only control translation, and not rotation. Link to comment Share on other sites More sharing options...
[To...] Posted February 1, 2021 Author Share Posted February 1, 2021 Don't forget, we're using 1994..... Link to comment Share on other sites More sharing options...
[To...] Posted February 2, 2021 Author Share Posted February 2, 2021 Maybe the engineer should have specified ACB Link to comment Share on other sites More sharing options...
[Ri...] Posted February 2, 2021 Share Posted February 2, 2021 I don't have a copy of 1994 available. Is this section not there? I'll take a look at this in the other software that I have available that are ASME compliant. My suspicion is that if they wanted C involved, they would have had to make it A C B or put some explicit note talking about the intention of Datum C. Like I said, I've had customers throw this same requirement on a drawing, and all that existed was either Datum A or not Datums at all. People just click buttons and check boxes. Link to comment Share on other sites More sharing options...
[To...] Posted February 2, 2021 Author Share Posted February 2, 2021 Please sign in to view this quote. I don't have 1994 either but I believe the individual translation and rotation controls were added in 2009. Where's Mark Foster when you need him? Link to comment Share on other sites More sharing options...
[SH...] Posted February 2, 2021 Share Posted February 2, 2021 Is there is any special in 1994, at the moment iam working in a US company in India.. All the drawing are 1994 standard.. 😠 😠 Link to comment Share on other sites More sharing options...
[To...] Posted February 2, 2021 Author Share Posted February 2, 2021 https://www.qualitydigest.com/pdfs/Revi ... andard.pdf https://www.asme.org/codes-standards/fi ... olerancing Link to comment Share on other sites More sharing options...
[SH...] Posted February 2, 2021 Share Posted February 2, 2021 Please sign in to view this quote. 🙂 Link to comment Share on other sites More sharing options...
[Ri...] Posted February 2, 2021 Share Posted February 2, 2021 I don't see anything concrete in 1994. There is a note about order of precedence, but the standard does not cover every possibility. My initial testing with a different software which allows you to select which revision of Y14.5 you want to measure to fully constrains the DRF with A B, and while it does allow you to select C, it has not impact on the results. I have one more software to test. Link to comment Share on other sites More sharing options...
[Ri...] Posted February 2, 2021 Share Posted February 2, 2021 I found this from Quality Magazine. https://www.qualitymag.com/ext/resource ... pdated.pdf Capture.PNG Link to comment Share on other sites More sharing options...
[An...] Posted February 2, 2021 Share Posted February 2, 2021 _ Link to comment Share on other sites More sharing options...
[SH...] Posted February 2, 2021 Share Posted February 2, 2021 Please sign in to view this quote. If datum B is a square it controls the rotation so C is superfluous?? Link to comment Share on other sites More sharing options...
[An...] Posted February 3, 2021 Share Posted February 3, 2021 _ Link to comment Share on other sites More sharing options...
[To...] Posted February 3, 2021 Author Share Posted February 3, 2021 Please sign in to view this quote. See Richard's post from 2/1/2021 5:44pm It walks you through the diagraph that both he and Andreas posted. Link to comment Share on other sites More sharing options...
[To...] Posted February 3, 2021 Author Share Posted February 3, 2021 Ok. I tried to get into the mind of the engineer. So, for the A B C DRF, I created the following secondary alignment. Spatial Rotation: Cylinder_Datum A Planar Rotation: Symmetry Plane_Datum C X Origin: Parallel Cylinders_Datum B (could have used a Symmetry Construction of the 2 Datum B Cylinders) Y Origin: Cylinder_Datum A Z Origin: Cylinder_Datum A Hope everyone is happy now, but I'm guessing someone won't be. Link to comment Share on other sites More sharing options...
[Ri...] Posted February 3, 2021 Share Posted February 3, 2021 Please sign in to view this quote. But Tom... that's not what the standard says to do. You are going to get into big trouble not following the standard to a t. Link to comment Share on other sites More sharing options...
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