Part Design Additive Pipe pathing issue

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nerstuff
Posts: 3
Joined: Tue Sep 27, 2022 3:02 am

Part Design Additive Pipe pathing issue

Post by nerstuff »

Hello,

New FreeCAD user here.

Problem summary:
When I highlight both the "Lip Outline" and the "Bin Outline Shapebinder" in the Model tree view, then select the Part Design workbench's Additive Pipe, I get several unhelpful errors, such as "Recompute failed! Please check report view." and the empty Error dialog shown in the attached screenshot.


My questions:
Q1: Is there a better/more recommended way to place the Bin Outline so it is accessible from multiple Bodies?
Q2: Is there a way to get more information when the "Please check report view" message arrives? Is there another "report view" I'm not aware of?
Q3: Am I using Shapebinder incorrectly? How else can I give multiple Body sketches access to the same path? I'm currently using Shapebinder, then Import External Geometry in the Sketcher to give the sketch access to the Bin Outline path.
Q4: Is there a problem in my Bin Outline path that is causing the issue?

Thank you much.

What have I tried?

The on-screen preview shows a small gap in the upper-left portion on the extruded part. Thinking that maybe there is a path issue that is causing the problem, I have reconstructed that portion of the path several times, but it doesn't appear to solve the problem.

Background information:

I am attempting to make a cover for a bin. The first Body will be the Flat part of the cover (not shown or included in the attached file) and the second Body will be a U-shaped Lip that fit onto the top edge of the bin. (In the attached file, I have simplified the Lip shape to be a simple square on the Y-Z plane.)

Since I will be using the Bin Outline for two Bodies, I have put the Bin Outline outside of the Part and I am using Shapebinders to give each Body access to the path. (Please let me know if there is a better way to do this.)

I have created the path in the X-Y plane that describes the outline of the bin.
I pad the Bin Outline to create the Flat top. (Not included in the attached file)
I use Additive Pipe to trace the Lip Outline around the Bin Outline to create the Lip.
I plan to join both the Flat top and Lip Outline together as a single part.

OS: macOS 10.16
Word size of FreeCAD: 64-bit
Version: 0.20.1.29410 (Git)
Build type: Release
Branch: (HEAD detached at 0.20.1)
Hash: f5d13554ecc7a456fb6e970568ae5c74ba727563
Python 3.10.5, Qt 5.15.4, Coin 4.0.0, Vtk 9.1.0, OCC 7.6.2
Locale: C/Default (C)
Installed mods:
* fasteners 0.4.6
* Curves 0.5.8
Attachments
PathErrorExample.FCStd
(52.77 KiB) Downloaded 24 times
FreeCAD error screenshot.png
FreeCAD error screenshot.png (697.9 KiB) Viewed 732 times
chrisb
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Posts: 53930
Joined: Tue Mar 17, 2015 9:14 am

Re: Part Design Additive Pipe pathing issue

Post by chrisb »

You basically try to make sweep's section and path the same.
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nerstuff
Posts: 3
Joined: Tue Sep 27, 2022 3:02 am

Re: Part Design Additive Pipe pathing issue

Post by nerstuff »

Ok, so I think I've solved the issue. It looks like the resolver doesn't like constraints with negative distances.

When I was originally adding the horizontal and vertical distance contraints, I would click on one point, hold shift and click on the second point, then click on the horizontal or vertical constraint button. The dialog pops up with the distance pre-filled.

For 3 or 4 of those contraints, the pre-filled distance was a negative value. I tried deleting the negative sign but it kept wanting to come back. Being a newbie, I shrugged my shoulders, and pressed "OK".

Looks like that came back to bite me. The resolver kept complaining. Several other solutions (getting rid of all contructions, removing the large diameter arc at the top and replacing with a straight line) did not solve the issue. But removing all the negative constraints and replacing them with positive constraints (for some reason the dialog presented all positive values distances this time) and the Additive Pipe works. Huzzah!
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Shalmeneser
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Posts: 9475
Joined: Wed Dec 23, 2020 12:04 am
Location: Fr

Re: Part Design Additive Pipe pathing issue

Post by Shalmeneser »

I've got no problem with your pipe, just bad geometry : Part_CheckGeometry

Code: Select all

OS: Windows 10 Version 1809
Word size of FreeCAD: 64-bit
Version: 0.21.30058 (Git)
Build type: Release
Branch: master
Hash: cb96332a64db8ae855ca700212eebb0f5151230a
Python 3.10.5, Qt 5.15.4, Coin 4.0.0, Vtk 9.1.0, OCC 7.6.2
Locale: French/France (fr_FR)
Installed mods: 
  * fasteners 0.4.3
  * fcgear 1.0.0
  * Manipulator 1.4.9
  * sheetmetal 0.2.56
Your master sketch is too complex. You should be able to modify a fillet without modifying the whole form.
Attachments
PathErrorExample_SHALM.FCStd
(25.88 KiB) Downloaded 13 times
Capture d’écran 2022-09-28 124113.jpg
Capture d’écran 2022-09-28 124113.jpg (33.46 KiB) Viewed 558 times
nerstuff
Posts: 3
Joined: Tue Sep 27, 2022 3:02 am

Re: Part Design Additive Pipe pathing issue

Post by nerstuff »

Thank you for your time spent cleaning up my file to show a better way to do the job.

If I understand correctly, the first drawing is a general outline (basically "construction geometry"?) while second drawing builds on the first but includes the curves needed to make the final path?

I have a lot to learn. Thanks again for your time and insight.
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Shalmeneser
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Posts: 9475
Joined: Wed Dec 23, 2020 12:04 am
Location: Fr

Re: Part Design Additive Pipe pathing issue

Post by Shalmeneser »

nerstuff wrote: Fri Sep 30, 2022 1:28 am If I understand correctly, the first drawing is a general outline (basically "construction geometry"?) while second drawing builds on the first but includes the curves needed to make the final path?
Correct. All could be done in the same sketch with the outline in construction mode (blue lines). But there are too much dimensions for me in the same sketch.

KISS : keep it stupidly simple
And the fillets should always be independant from the outline : use the second fillet mode (Fillet keeping constraints).
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