MillFace operation and "Clear Edges" option

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jffmichi
Posts: 22
Joined: Sun Feb 23, 2020 11:25 pm

MillFace operation and "Clear Edges" option

Post by jffmichi »

Hello,

first let me thank you all and especially Russ4262 for the amazing work you're putting into FreeCAD. I'm a huge fan of open source software and FreeCAD is now at a place where I can do almost everything I currently need. However, I currently have an issue with the MillFace operation. There were some recent changes made by Russ4262 that broke my workflow a little bit. I already talked to him and he suggested opening a forum thread, so here I am.

I believe the changes come from this commit. Before this commit when selecting "Face Region" as boundary, the cutter would extend a little over one full diameter outwards which I liked very much. This is for two reasons:

a) it was possible to continue milling downwards on the border of the face without the need to clear material "above" the face, this was already taken care of by the MillFace operation (see before_a.png). After the changes, the best I could come up with, was using "Face Region" as boundary and enabling "Clear Edges" and "Exclude Raised Areas". But even then the cutter only extends one half diameter outwards which causes more material to remain outside and above the face. Then, when milling one "layer" downwards the cutter crashes into that material (see after_a.png). The "Extra Offset" value unfortunately doesn't help in this case because it doesn't respect the "Exclude Raised Areas" option.

b) sharp "spikes" on the corner of the face were milled correctly when using e.g. ZigZagOffset as pattern (see before_b.png). After the changes the cutter doesn't reach the tip of those spikes (see after_b.png).

Do you think it would be possible to make the extension of the face a numeric parameter instead of the boolean "Clear Edges" option? I have no idea if this would break other things or if it would be difficult from an implementation perspective.

Thank you all for your time and effort!
jffmichi
Attachments
before_a.png
before_a.png (355.85 KiB) Viewed 1690 times
after_a.png
after_a.png (277.23 KiB) Viewed 1690 times
before_b.png
before_b.png (52.56 KiB) Viewed 1690 times
after_b.png
after_b.png (43.12 KiB) Viewed 1690 times
MillFaceExample.FCStd
(45.91 KiB) Downloaded 44 times
Russ4262
Posts: 941
Joined: Sat Jun 30, 2018 3:22 pm
Location: Oklahoma
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Re: MillFace operation and "Clear Edges" option

Post by Russ4262 »

jffmichi wrote: Tue Oct 19, 2021 10:57 pm Hello, ...
Afternoon.
I am not in front of a FreeCAD terminal ATM, but it should be possible to use the PocketShape operation to achieve what you need. It offers almost the same clearing options (without Boundary Shape selection) with the added benefit of the Extensions feature. I suggest giving it a try.

I see that MillFace is a little buggy with certain Extra Offset values, but I do not know why. When I get a chance, I will compare old code prior to the recent change with the new code to see if I can identify the procedural change that is causing the issue.

Thanks for reporting this issue.
Russell
jffmichi
Posts: 22
Joined: Sun Feb 23, 2020 11:25 pm

Re: MillFace operation and "Clear Edges" option

Post by jffmichi »

Ah that's nice. It's already there and works exactly as I need it. Thanks a lot!
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