Sweep Errors

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caunyd
Posts: 30
Joined: Sun Dec 15, 2019 4:58 am

Sweep Errors

Post by caunyd » Mon Mar 30, 2020 7:21 am

Hi guys. I'm having difficulty with this sweep. Upon checking geometry, there are the following errors:

1/ Solid - invalid
2/ Shell - sub shape not in shape

I am aware that I can split up the sweep path to multiple smaller ones, but when I do this, the sweeps seem not as refined, even when combined. So with the sweep the way I have it now, how do I being to fix these errors? Thanks!
Attachments
Sweep Problem.FCStd
(89.9 KiB) Downloaded 5 times
kisolre
Posts: 2102
Joined: Wed Nov 21, 2018 1:13 pm

Re: Sweep Errors

Post by kisolre » Mon Mar 30, 2020 8:32 am

Main problem was "almost" tangencies. These often give errors. I also properly mapped section sketch to the beginning of the path. I assume that is how you want it.
Attachments
Sweep Problem_kiss.FCStd
(18.85 KiB) Downloaded 3 times
caunyd
Posts: 30
Joined: Sun Dec 15, 2019 4:58 am

Re: Sweep Errors

Post by caunyd » Mon Mar 30, 2020 8:40 am

Yes! Thanks you Kisolre! So you solved it by slightly redoing the sweep path to avoid those "almost tangencies" ?
chrisb
Posts: 24233
Joined: Tue Mar 17, 2015 9:14 am

Re: Sweep Errors

Post by chrisb » Mon Mar 30, 2020 8:49 am

Besides that, your sketches should receive some love. You should always aim at fully constrained sketches. You should prefer geometric constraints over dimensions. Repeating dimensions is not always wrong, but it always has a bad smell. Furthermore in the Path you have lots of useless points. Remove them and your sketch will have only two degrees of freedom left.
caunyd
Posts: 30
Joined: Sun Dec 15, 2019 4:58 am

Re: Sweep Errors

Post by caunyd » Mon Mar 30, 2020 9:08 am

chrisb, that's why I come here for the masters ;) . For the path, I felt that I used what I needed to get the path I wanted. I don't know how I could do it without those points. Can you point out which points are useless and how I could do it more efficiently? Thanks chrisb
chrisb
Posts: 24233
Joined: Tue Mar 17, 2015 9:14 am

Re: Sweep Errors

Post by chrisb » Mon Mar 30, 2020 10:06 am

Look at the elements list to the left and remove all the points. They don't contribute anything. I have added two radius dimensions, to make the sketch fully constrained. The numbers look rather weird here, perhaps because I'm using metric units.

This is your profile before reworking it:
Snip macro screenshot-c04484.png
Snip macro screenshot-c04484.png (29.26 KiB) Viewed 115 times
It contains 12 elements 33 constraints with 13 dimensions and shows 3 degrees of freedom. I reworked it and had quite some time to search for the last two degrees of freedom, which came from an again completely useless point far away from the sketch.

Here is the result:
Snip macro screenshot-818f7a.png
Snip macro screenshot-818f7a.png (25.18 KiB) Viewed 115 times
It contains 10 elements, 26 constraints, and only 7 dimensions and is fully constrained.
Attachments
SweepProblem_cb.FCStd
(17.12 KiB) Not downloaded yet
caunyd
Posts: 30
Joined: Sun Dec 15, 2019 4:58 am

Re: Sweep Errors

Post by caunyd » Tue Mar 31, 2020 2:28 pm

ok I'm seeing it. Thanks chrisb
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