Interesting info re 3D printing, FreeCAD and OpenSCAD

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keithsloan52
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Interesting info re 3D printing, FreeCAD and OpenSCAD

Post by keithsloan52 »

Interesting article from April 2021 on the use of FreeCAD and the OpenSCAD workbench related to 3D printing
from the Guru of RepRap printing Adrian Bowyer https://reprapltd.com/3d-printing-clearance-and-fit/
TheMarkster
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Re: Interesting info re 3D printing, FreeCAD and OpenSCAD

Post by TheMarkster »

He has posted occasionally on this forum. Very interesting read. Now I know what Minkowski does. You need to 2 objects and it gives you something akin to an offset. He wasn't kidding about it being computationally intensive.
keithsloan52
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Re: Interesting info re 3D printing, FreeCAD and OpenSCAD

Post by keithsloan52 »

TheMarkster wrote: Wed Oct 27, 2021 1:18 am He wasn't kidding about it being computationally intensive.
Would love to see FreeCAD & OpenSCAD running on NVIDIA Jetson Nano, then maybe somebody could develop new code to exploit GPU's for Hull & Minkowski.
RatonLaveur
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Re: Interesting info re 3D printing, FreeCAD and OpenSCAD

Post by RatonLaveur »

The workflow using both FreeCAD and OpenSCAD seems a bit convoluted. Doesn't Draft Offset/Part Offset or Sketcher Offset offer a solution to the problem?
keithsloan52
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Re: Interesting info re 3D printing, FreeCAD and OpenSCAD

Post by keithsloan52 »

RatonLaveur wrote: Sat Nov 06, 2021 7:11 pm The workflow using both FreeCAD and OpenSCAD seems a bit convoluted. Doesn't Draft Offset/Part Offset or Sketcher Offset offer a solution to the problem?
Well the part concerned is in https://github.com/RepRapLtd/RobotCompo ... otor.FCStd

I reduced it to just what is called hall-coils
justCoils.FCStd
(75.51 KiB) Downloaded 73 times
Don't see any sketch but don't see why it should not have been constructed with a sketch

And when I try a Part::Offset I get an error BRepOffsetAPI_MakeOffsetShape Not Done :-(

Code: Select all

OS: macOS 10.15
Word size of FreeCAD: 64-bit
Version: 0.20.25645 (Git)
Build type: Release
Branch: master
Hash: 37d9757399b4c2ec30318eb88d7cd7c508246345
Python version: 3.9.7
Qt version: 5.12.9
Coin version: 4.0.0
OCC version: 7.5.2
Locale: C/Default (C)
RatonLaveur
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Re: Interesting info re 3D printing, FreeCAD and OpenSCAD

Post by RatonLaveur »

keithsloan52 wrote: Sat Nov 06, 2021 10:23 pm
And when I try a Part::Offset I get an error BRepOffsetAPI_MakeOffsetShape Not Done :-(
Bug report?
hmk
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Re: Interesting info re 3D printing, FreeCAD and OpenSCAD

Post by hmk »

keithsloan52 wrote: Sat Nov 06, 2021 10:23 pm And when I try a Part::Offset I get an error BRepOffsetAPI_MakeOffsetShape Not Done :-(
Just to be sure, are you taking about 3D Offset? https://wiki.freecadweb.org/Part_Offset

What do you want to accomplish? It seem to me it's hard to arrive at a meaningful result with this transformation because it "warps" the part quite a bit.

I have not used 3D Offset before, it behaves a rather flaky on me, but with some settings you can get a result. For example with a single coil and the original GitHub file:
Screenshot from 2021-11-28 15-35-50.png
Screenshot from 2021-11-28 15-35-50.png (96.34 KiB) Viewed 6921 times
OS: PureOS (GNOME/gnome)
Word size of FreeCAD: 64-bit
Version: 0.20.26375 (Git) AppImage
Build type: Release
Branch: (HEAD detached at 8a6e3d1)
Hash: 8a6e3d1b766a34546806b22d750929c2d00e30a6
Python version: 3.9.7
Qt version: 5.12.9
Coin version: 4.0.0
OCC version: 7.5.3
Locale: English/United States (en_US)
keithsloan52
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Re: Interesting info re 3D printing, FreeCAD and OpenSCAD

Post by keithsloan52 »

hmk wrote: Sun Nov 28, 2021 2:37 pm
keithsloan52 wrote: Sat Nov 06, 2021 10:23 pm And when I try a Part::Offset I get an error BRepOffsetAPI_MakeOffsetShape Not Done :-(
Just to be sure, are you taking about 3D Offset? https://wiki.freecadweb.org/Part_Offset

What do you want to accomplish? It seem to me it's hard to arrive at a meaningful result with this transformation because it "warps" the part quite a bit.
I was just responding to
RatonLaveur wrote: Sat Nov 06, 2021 7:11 pm The workflow using both FreeCAD and OpenSCAD seems a bit convoluted. Doesn't Draft Offset/Part Offset or Sketcher Offset offer a solution to the problem?
Who was suggesting that rather than use the approach suggested by Adrian Bowyer you could just use a 3D offset.
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