Re: PR #5357 - add feature to create tapered Pads / Pockets
Posted: Sun Jan 09, 2022 1:48 pm
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Uh, this is not a very satisfying explanation. If the user didn’t want the inner wires to be part of the pad, then he/she would not have included it in their sketch. I vote for the following behavior: If outer contour grows then inner contour should shrink.uwestoehr wrote: ↑Sun Jan 09, 2022 1:47 pm This is on purpose because I took purposely the Part Extrude code. If there is a taper angle, it only takes the outer wire of the sketch to extrude.
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- for example if you have a circular hole in your sketch, you probably don't want to have it a taper angle, only for the outer sketch wire
- if you have an inner wire, you might want to have a different taper angle. For example when molding plastics the shrinkage is volume-dependent and then the inner taper angles might indeed have different values
+1davidosterberg wrote: ↑Sun Jan 09, 2022 3:56 pm Uh, this is not a very satisfying explanation. If the user didn’t want the inner wires to be part of the pad, then he/she would not have included it in their sketch. I vote for the following behavior: If outer contour grows then inner contour should shrink.
My guess is rather that it takes extra work to make it handle multiple wires, and that work just has not been done yet. Just like PartDesign's Pad/Pocket have been around for ages without tapered flanks...uwestoehr wrote: ↑Sun Jan 09, 2022 1:47 pm This is on purpose because I took purposely the Part Extrude code. If there is a taper angle, it only takes the outer wire of the sketch to extrude.
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Part's Extrude feature is there for ages and obviously people can live that inner wires are not extruded when there is a taper angle.
True, but I'd consider those as special cases. If you really need them, you just use two consecutive pad/pocket operations. But as a user, if I pad/pocket a sketch with nested wires, I'd consider it a bug if all but the outer most wire are just ignored.uwestoehr wrote: ↑Sun Jan 09, 2022 1:47 pm One could also take the inner wires as PartDesign Loft does so there must be a reason. And when thinking on how to implement the tapered option for inner wires I can imagine why these are not handled:
- for example if you have a circular hole in your sketch, you probably don't want to have it a taper angle, only for the outer sketch wire
- if you have an inner wire, you might want to have a different taper angle. For example when molding plastics the shrinkage is volume-dependent and then the inner taper angles might indeed have different values
This is exactly what I'd expect to happen -- without any enumeration.TheMarkster wrote: ↑Sun Jan 09, 2022 3:47 pm ...
Taper all wires, but inner wires are inverted. Example: outer wire is tapered 2 degrees, inner wires -2 degrees
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For ages the Extrude feature behaves as it does. Now I just transferred tits functionality to Pad/Pocket. So I add a feature, all existing functionalities are preserved.
I know. It is not "failing" it purposely doesn't handle them. As said, this will be stage 2 and I am already trying to make Extrude take care of inner wires in sketches.TheMarkster wrote: ↑Sun Jan 09, 2022 4:21 pm Extrude is managing to taper both wires, it's just failing to boolean cut the inner from the outer.
Ah, good. I think there was cross-posting and I didn't notice the bit about doing this in stages. I think there are also related issues with Part Loft and Sweep not managing inner wires. In fact, such profiles do not even appear in the dialog as options. By the way, if a student refuses to take an exam he still gets a failing grade even if he knew the material and purposely did not answer the questions.uwestoehr wrote: ↑Sun Jan 09, 2022 4:23 pmI know. It is not "failing" it purposely doesn't handle them. As said, this will be stage 2 and I am already trying to make Extrude take care of inner wires in sketches.TheMarkster wrote: ↑Sun Jan 09, 2022 4:21 pm Extrude is managing to taper both wires, it's just failing to boolean cut the inner from the outer.
What? Are you my professor?TheMarkster wrote: ↑Sun Jan 09, 2022 4:39 pm By the way, if a student refuses to take an exam he still gets a failing grade