Section view hatch without a rib

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NewJoker
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Re: Section view hatch without a rib

Post by NewJoker »

@Shalmeneser

Thank you for sharing that workaround.

Shalmeneser wrote: Thu May 26, 2022 3:37 pm https://youtu.be/rTmGJMJn9Og
Yes, that's the video I was talking about. One hour ago its author published another video in which he fixed the drawing in SolidEdge 2D Drafting which is theoretically free for now but of course not open-source. Still, I would prefer a solution in FreeCAD or with the help of other FOSS tools.

So, to sum up - it can be done only roughly in FreeCAD using the workaround with cutting the 3D model. Maybe Inkscape or LibreCAD could help.

One more potential solution came to my mind that could be implemented in the future in addition to sketching in TechDraw. What if we were able to convert the view (section view in this case) to Draft, modify it there and then convert back to TechDraw ?
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RedBaron
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Re: Section view hatch without a rib

Post by RedBaron »

@NewJoker
In the case of views of sections passing through object's walls, ribs or spokes, those features are drawn in a view as if they were placed right behind the section plane.
Do the rules for sectional representation of ribs refer to to ISO 128-40 & -44 ?
In SolidWorks there's an option to exclude rib operations from hatching. But this is because SW has a special tool for easier creation of ribs. It could be also useful in FreeCAD but that's another topic.
Is this a function which hides hatch lines , possibly similar to Siemens SolidEdge?

https://docs.sw.siemens.com/en-US/produ ... /dvhatch1h

Maybe in the video in the following link a possibility is shown by using Part Workbench and the Slice function:
https://www.youtube.com/watch?v=Dg2szQ3xpAw

I am also interested in other suggestions.
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NewJoker
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Re: Section view hatch without a rib

Post by NewJoker »

NewJoker wrote: Thu May 26, 2022 10:00 pm One more potential solution came to my mind that could be implemented in the future in addition to sketching in TechDraw. What if we were able to convert the view (section view in this case) to Draft, modify it there and then convert back to TechDraw ?
I went back to this to test another workaround. Here's what I did:
1) Part SectionCut to cut the part in the same way as it's done by the section view tool in this case.
2) Draft Shape2DView to create a 2D line representation of the cut part.
3) Draft Line with proper snaps to separate the rib from the rest of the section view.
4) Draft Upgrade twice to create a single object out of all those lines.
5) TechDraw View to create a view of this object in TechDraw.

After that, I can hatch selected regions but unfortunately not all of them:

hatched.png
hatched.png (27.26 KiB) Viewed 1587 times

I attached the file here:
Clothes hanger body new.FCStd
(601.7 KiB) Downloaded 45 times

Is there a way to make that missing region on the left selectable for hatching ? I would also like to remove hatch from the narrow trapezoidal area on the right. With these two modifications the section view would look pretty much the same as in SolidWorks:

sw.JPG
sw.JPG (75.96 KiB) Viewed 1587 times
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wandererfan
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Re: Section view hatch without a rib

Post by wandererfan »

NewJoker wrote: Tue Aug 23, 2022 1:29 pm Is there a way to make that missing region on the left selectable for hatching ? I would also like to remove hatch from the narrow trapezoidal area on the right. With these two modifications the section view would look pretty much the same as in SolidWorks:
Section faces aren't selectable and can't be changed individually. Allowing changes to the section faces has been discussed before, but has never made up to the top of the todo list.
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NewJoker
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Re: Section view hatch without a rib

Post by NewJoker »

wandererfan wrote: Wed Aug 24, 2022 1:51 pm Section faces aren't selectable and can't be changed individually. Allowing changes to the section faces has been discussed before, but has never made up to the top of the todo list.
All right but in my case, it's a regular view, not a section view. However, it's a view of the Draft object. In such a case is it also impossible to influence the selectability of individual faces ?
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wandererfan
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Re: Section view hatch without a rib

Post by wandererfan »

NewJoker wrote: Wed Aug 24, 2022 2:02 pm All right but in my case, it's a regular view, not a section view. However, it's a view of the Draft object. In such a case is it also impossible to influence the selectability of individual faces ?
It isn't because it is a Draft object, but because the face finder gets confused by the overlapping edges on the curve.
oldFaceFinderOverlapEdges.png
oldFaceFinderOverlapEdges.png (21.38 KiB) Viewed 1473 times
There is a new face finder coming that can handle these overlapping edges.
newFaceFinderRib.png
newFaceFinderRib.png (37.64 KiB) Viewed 1473 times
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NewJoker
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Re: Section view hatch without a rib

Post by NewJoker »

wandererfan wrote: Wed Aug 24, 2022 4:04 pm It isn't because it is a Draft object, but because the face finder gets confused by the overlapping edges on the curve.
This particular face is supposed to remain unhatched (that's the purpose of this workaround with Draft). I want to hatch this one:

face.PNG
face.PNG (8.43 KiB) Viewed 1446 times

For some reason, I can select and hatch it now (I wasn't able to do this yesterday on a different machine). However, the narrow trapezoidal faces are also selected and hatched together with the main faces:

faces.PNG
faces.PNG (30.98 KiB) Viewed 1446 times

Is it possible to exclude them somehow ?

wandererfan wrote: Wed Aug 24, 2022 4:04 pm There is a new face finder coming that can handle these overlapping edges.
Cool, good to know.
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wandererfan
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Re: Section view hatch without a rib

Post by wandererfan »

NewJoker wrote: Wed Aug 24, 2022 5:13 pm For some reason, I can select and hatch it now (I wasn't able to do this yesterday on a different machine). However, the narrow trapezoidal faces are also selected and hatched together with the main faces:
Being able to select on one machine and not another may be due to the EdgeFuzz setting (Advanced tab) being different. If 2 edges have overlapping selection areas, you might not be able to select the face underneath.

The small trapezoids in Group are not closed. Faces have to be closed regions to be detected.
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NewJoker
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Re: Section view hatch without a rib

Post by NewJoker »

@wandererfan Thank you very much. I converted the Draft object to sketch and fixed some issues with it. Here's the final result:

fixed.png
fixed.png (36.98 KiB) Viewed 1367 times

It's pretty much the same as in SW :D
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