[An...] Posted September 24, 2020 Share Posted September 24, 2020 Deleted. Link to comment Share on other sites More sharing options...
[Jo...] Posted September 24, 2020 Share Posted September 24, 2020 What does this contribution even mean? I see a coordinate system that is rotated but why? Why does the last page show datum plane B completely off of datum feature B? That datum plane should be right along the datum feature. Link to comment Share on other sites More sharing options...
[To...] Posted September 24, 2020 Author Share Posted September 24, 2020 Attached are the results of my test. When I created the theoretical plane, I copied Datum C and made it theoretical. When I saw the results, I realized that this plane was controlled by the Base Alignment, which is using LSQ evaluations and not constrained per ISO5459. I could change it, but why? Result is similar to Datum BA but this uses OTE and ISO5459 The best result, and I believe the correct result, was using Datum B as the Primary, but constraining it to Datum A. This constraint actually makes A the primary and B establishes the 40° angle.angularity results.pdfang 1.jpgang 2.jpgang 3.jpgang 4.jpg Link to comment Share on other sites More sharing options...
[An...] Posted September 24, 2020 Share Posted September 24, 2020 Deleted. Link to comment Share on other sites More sharing options...
[An...] Posted September 25, 2020 Share Posted September 25, 2020 Deleted. Link to comment Share on other sites More sharing options...
[Jo...] Posted September 25, 2020 Share Posted September 25, 2020 Attached is my understanding of what the datum reference frame should look like per ASME. I still don't understand the updated contribution.Angularity_question.png Link to comment Share on other sites More sharing options...
[Ma...] Posted September 25, 2020 Share Posted September 25, 2020 John i think that this you can achieve only with theoretical plane or line derived from B base by base angle 40. Then check angularity for 90°. If you use B as primary and A as secondary, then you can use angularity for base angle 40, but it will bad against drawing. Link to comment Share on other sites More sharing options...
[Br...] Posted September 25, 2020 Share Posted September 25, 2020 Please sign in to view this quote. Good stuff. It's basically the same thing you have to do when you have a runout tolerances to multiple datum references in Calypso because you don't have the option for the second datum reference. Just constrain the secondary to the primary and use the secondary in the characteristic. Link to comment Share on other sites More sharing options...
[An...] Posted September 26, 2020 Share Posted September 26, 2020 Deleted. Link to comment Share on other sites More sharing options...
[An...] Posted September 28, 2020 Share Posted September 28, 2020 Deleted. Link to comment Share on other sites More sharing options...
[Ja...] Posted September 28, 2020 Share Posted September 28, 2020 Couldn't you just create the alignment you want and check it as profile of datum C? Intersect plane A, B, and C. Use the intersection as X, Y, and Z zero. Use A as spatial, B as planar, and ask for profile of C relative to your new alignment. Or, will that be the same as using B as primary constrained to A? Link to comment Share on other sites More sharing options...
[Ja...] Posted September 28, 2020 Share Posted September 28, 2020 I take that back. I think my alignment would be adding X,Y locations that are not required in the angularity call out. Link to comment Share on other sites More sharing options...
[Ri...] Posted September 28, 2020 Share Posted September 28, 2020 Please sign in to view this quote. You'll be pleased to see it is now available in 2020. 😉 😉 Link to comment Share on other sites More sharing options...
[An...] Posted September 29, 2020 Share Posted September 29, 2020 Deleted. Link to comment Share on other sites More sharing options...
[Br...] Posted September 29, 2020 Share Posted September 29, 2020 Please sign in to view this quote. Because you said so? Link to comment Share on other sites More sharing options...
[Me...] Posted September 30, 2020 Share Posted September 30, 2020 Please sign in to view this quote. Actually, Andreas is correct. The order of precedence is being ignored when |B| is used as the primary datum within the angularity characteristic, even though |B| is being constrained to |A|. Doing this is equivalent as using an (OTE) 2d-Line as the primary datum where the measured points of |B| have been projected onto |A|. If you must use the angularity characteristic, then do as Andreas suggested and create a theoretical plane that is set to an appropriate secondary alignment and parallel to the considered feature. Or use the secondary alignment within the considered feature, constrain the normal vector, and report the form. Link to comment Share on other sites More sharing options...
[Br...] Posted October 1, 2020 Share Posted October 1, 2020 Please sign in to view this quote. Although I don't really see it working that way because it is literally creating a theoretical plane that is perfectly perp to the plane you constrain it to--Even if what it did was project those high points onto the Primary datum plane, it still wouldn't break datum precedence for and angularity tolerance. It still constrains 2 degrees of rotation from datum feature A(Because you constrained datum feature B to A) and then uses the final 3rd rotational degree of freedom from B. Maybe I'm misunderstanding your point. Update: I thought this through some more and I think I see your point. There is one degree of freedom that wont be captured. coming from datum feature A. hmm Please sign in to view this quote. That's just cheating. if you constrain the actual feature to be evaluated for angularity to the datum features, you literally are only controlling form. You might as well just report flatness. Angularity controls orientation to the DRF. so if you constrain it to the DRF, you have forced the orientation perfect. Link to comment Share on other sites More sharing options...
[Me...] Posted October 1, 2020 Share Posted October 1, 2020 Please sign in to view this quote. Yep, it's not going to work. Please sign in to view this quote. Flatness would be the unconstrained feature using the “Minimum Feature” fit. The datum reference within the feature has no impact on that result. Please sign in to view this quote. The orientation of the substitute feature has been forced perfect. However, the reported form will now represent the orientation error since the constraints are being applied with respect to the DRF. If you have some free time, try it out on the other orientation controls. Please sign in to view this quote. “Workaround” sounds way more pleasant. 😎 I should also note that the evaluations methods proposed by Andreas and myself have been tested in another GD&T fitting software, and the results agree. Link to comment Share on other sites More sharing options...
[Br...] Posted October 1, 2020 Share Posted October 1, 2020 Please sign in to view this quote. I'm probably just not fully what you're talking about. It sounded like to me you wanted to take the feature being toleranced and constrain the vectors to the Datums, which makes its orientation perfect. That's why I called it cheating. Link to comment Share on other sites More sharing options...
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