Part -> sweep

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baltic
Posts: 24
Joined: Wed Sep 11, 2019 10:53 pm

Re: Part -> sweep

Postby baltic » Mon Oct 07, 2019 11:49 am

papyblaise wrote:
Mon Oct 07, 2019 11:04 am
but the question is why start to us Partdesign and continu whith PartWb , very bad idee
Coz Part Design crashes on those sketches. Does it crash for you?
baltic
Posts: 24
Joined: Wed Sep 11, 2019 10:53 pm

Re: Part -> sweep

Postby baltic » Mon Oct 07, 2019 12:00 pm

Apparently the latest 0.19 from github doesn't crash. But it still gives messages that don't make sense.
Increasing the radius from 3mm helps to solve the problem.
kisolre
Posts: 1360
Joined: Wed Nov 21, 2018 1:13 pm

Re: Part -> sweep

Postby kisolre » Mon Oct 07, 2019 12:21 pm

Because of the way sweep is constructed everything from the sweep profile that is on the inside of the sweep path must not be on more distance from the sweep path than the minimum sweep path curvature radius. Here marked dimension on first screenshot must be less than the marked dimension on the second screenshot for the sweep to succeed. Hope that makes sence.
InsideSweepDimension.JPG
InsideSweepDimension.JPG (39.42 KiB) Viewed 123 times
InsideSweepDimension2.JPG
InsideSweepDimension2.JPG (39.42 KiB) Viewed 123 times
baltic
Posts: 24
Joined: Wed Sep 11, 2019 10:53 pm

Re: Part -> sweep

Postby baltic » Mon Oct 07, 2019 1:16 pm

kisolre wrote:
Mon Oct 07, 2019 12:21 pm
Hope that makes sence.
Why would it? If i can change sweep curve radius to 4mm, do sweep, change it back to 3mm, and it magically works. But it can't, for some reason, do the sweep with the original 3mm curvature radius directly, without the intermediate 4mm step.
How could it possibly make sense?
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papyblaise
Posts: 725
Joined: Thu Jun 13, 2019 4:28 pm
Location: France

Re: Part -> sweep

Postby papyblaise » Mon Oct 07, 2019 1:43 pm

I say you again and again , you can't bend the pipe whith a inside raduis = 0 or negative , you must have to 0.01mm minimum , use a raduis =3.01mm (in sketch005) and Bingo :!: :!: :!:
baltic
Posts: 24
Joined: Wed Sep 11, 2019 10:53 pm

Re: Part -> sweep

Postby baltic » Mon Oct 07, 2019 2:03 pm

papyblaise wrote:
Mon Oct 07, 2019 1:43 pm
I say you again and again , you can't bend the pipe whith a inside raduis = 0 or negative , you must have to 0.01mm minimum , use a raduis =3.01mm (in sketch005) and Bingo :!: :!: :!:
I don't even know what "raduis = 0 or negative" you are talking about.
But anyway, i can. and do. i just have to do it through an intermediate step which doesn't make sense.
baltic
Posts: 24
Joined: Wed Sep 11, 2019 10:53 pm

Re: Part -> sweep

Postby baltic » Mon Oct 07, 2019 2:15 pm

Ok, so if i change the curve to be completely outside of the resulting sweep figure, it works, even with curvature radius of 1mm
1.png
1.png (4.68 KiB) Viewed 106 times
Shall this be reported as a bug? Coz if tool requires the curve to be outside, it should check it first.
Also the error messages could be less cryptic. And the fact that it works even with the curve inside, just in two steps, is also weird.
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papyblaise
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Location: France

Re: Part -> sweep

Postby papyblaise » Mon Oct 07, 2019 2:34 pm

bend radius
now if somebody understand , explain him , I 'm very tired
Attachments
bend radius.PNG
bend radius.PNG (23.07 KiB) Viewed 103 times
baltic
Posts: 24
Joined: Wed Sep 11, 2019 10:53 pm

Re: Part -> sweep

Postby baltic » Mon Oct 07, 2019 3:04 pm

papyblaise wrote:
Mon Oct 07, 2019 2:34 pm
now if somebody understand , explain him , I 'm very tired
get a sleep and start over ;)
I've got you, it just still doesn't make sense that if you change it aftewards, it works, even with "raduis = 0 or negative".
kisolre
Posts: 1360
Joined: Wed Nov 21, 2018 1:13 pm

Re: Part -> sweep

Postby kisolre » Mon Oct 07, 2019 3:11 pm

baltic wrote:
Mon Oct 07, 2019 2:03 pm
But anyway, i can. and do. i just have to do it through an intermediate step which doesn't make sense.
The internal cylindrical face degrades to a line. Because of rounding errors/number representation/sketch solver precision/... this line could sometimes still be interpreted as a face and ócasionally work. If the sweep profile in inside more than the bend radius this creates selfintersecting surface which should not be valid. Checking geometry with 2.9mm bend radius gives a lot of errors - the "-0.1" radius.
Attachments
InternalFace.JPG
InternalFace.JPG (41.26 KiB) Viewed 98 times
InternalFace_Selfintersection.JPG
InternalFace_Selfintersection.JPG (117.42 KiB) Viewed 98 times
InternalFace_Selfintersection_transparent.JPG
InternalFace_Selfintersection_transparent.JPG (46.76 KiB) Viewed 98 times