How to get part of an entity ?

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eason
Posts: 120
Joined: Thu Apr 09, 2015 2:40 am
Location: Taiwan

How to get part of an entity ?

Postby eason » Wed Apr 01, 2020 1:23 am

I get a solid from my step file.
1.JPG
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I want part of the solid.
2.JPG
2.JPG (9.12 KiB) Viewed 196 times
How can i get it quicky ?

3213231.stp
(579.02 KiB) Downloaded 6 times
freedman
Posts: 1421
Joined: Thu Mar 22, 2018 3:02 am
Location: Washington State, USA

Re: How to get part of an entity ?

Postby freedman » Wed Apr 01, 2020 2:29 am

I took it into Draft, exploded it and erased all the stuff. Here it is! As soon as I exploded it the assembly broke into objects.
Attachments
bracket1.FCStd
(845.46 KiB) Downloaded 2 times
TheMarkster
Posts: 1373
Joined: Thu Apr 05, 2018 1:53 am

Re: How to get part of an entity ?

Postby TheMarkster » Wed Apr 01, 2020 3:08 am

This file does have some issues, which might or might not make it unusable for your intended purposes, according to the check geometry tool. These same defects were included in your original file. Manufacturers sometimes include intentional defects in step models.
Snip macro screenshot-308dcb.png
Snip macro screenshot-308dcb.png (140.79 KiB) Viewed 186 times
Attachments
solid.FCStd
(647.9 KiB) Not downloaded yet
My FreeCAD video series on youtube: https://www.youtube.com/c/mwganson
eason
Posts: 120
Joined: Thu Apr 09, 2015 2:40 am
Location: Taiwan

Re: How to get part of an entity ?

Postby eason » Wed Apr 01, 2020 3:37 am

freedman wrote:
Wed Apr 01, 2020 2:29 am
I took it into Draft, exploded it and erased all the stuff. Here it is! As soon as I exploded it the assembly broke into objects.
I also get the same result. (Face1 Face2 ....) Which I want is "Solid".

It means I need to merge these Faces to a Solid ?
TheMarkster
Posts: 1373
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Re: How to get part of an entity ?

Postby TheMarkster » Wed Apr 01, 2020 3:50 am

I downgraded to faces in Lattice2 workbench, deleted the ones I didn't need, and created one that was missing using the tool in Part workbench (shape builder in the menu) to create the missing face using face from edges, then created shell from faces, and then finally solid from shell.
My FreeCAD video series on youtube: https://www.youtube.com/c/mwganson
eason
Posts: 120
Joined: Thu Apr 09, 2015 2:40 am
Location: Taiwan

Re: How to get part of an entity ?

Postby eason » Wed Apr 01, 2020 4:02 am

TheMarkster wrote:
Wed Apr 01, 2020 3:50 am
I downgraded to faces in Lattice2 workbench, deleted the ones I didn't need, and created one that was missing using the tool in Part workbench (shape builder in the menu) to create the missing face using face from edges, then created shell from faces, and then finally solid from shell.
Yes, it is. I also generated SOLID like this.

I just want to know is there any way to do it quickly ?
kisolre
Posts: 2115
Joined: Wed Nov 21, 2018 1:13 pm

Re: How to get part of an entity ?

Postby kisolre » Wed Apr 01, 2020 8:11 am

Dont forget "step compound merge" - disabling that will not fuse different STEP solids so Exploding it later (which can take quite some time) will not be necessary.
.
StepCompoundMerge.JPG
StepCompoundMerge.JPG (102.43 KiB) Viewed 139 times
TheMarkster
Posts: 1373
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Re: How to get part of an entity ?

Postby TheMarkster » Wed Apr 01, 2020 3:58 pm

eason wrote:
Wed Apr 01, 2020 4:02 am
I just want to know is there any way to do it quickly ?
It depends on the file. In some cases you might get different compounds, in which case you already have the part separated from the others. Sometimes you can quickly defeature. Sometimes the only way to get a file that will actually work for your purposes is to remodel. As I mentioned earlier, this model has defects and might or might not be suitable for your intended purposes.
My FreeCAD video series on youtube: https://www.youtube.com/c/mwganson
kisolre
Posts: 2115
Joined: Wed Nov 21, 2018 1:13 pm

Re: How to get part of an entity ?

Postby kisolre » Mon Apr 06, 2020 7:38 am

eason wrote:
Mon Apr 06, 2020 12:43 am
How could I get it?
I dont understand... What you want to "get"?
If that setting is unchecked the STEP file is imported AS IS. If it is checked all shells under a single COMPOUND in the STEP are merged into a single object when importing the file. So if you want to be able to separate individual shells after the import better not merge them in the first place.