Pocket inside to outside

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usul27
Posts: 3
Joined: Sat Jun 25, 2022 1:04 pm

Pocket inside to outside

Post by usul27 »

I can't get FreeCAD to mill a pocket from the inside to the outside. Basically the same issue that's discuess here with an older version:
https://forum.freecadweb.org/viewtopic. ... =4&t=42619

On the top layer it just starts on the periphery :( There is a setting "Start From" that's set to center, but it doesn't seem to have any effect, the result is the same if I set his to Center or Edge.

Behaviour is the same with Pocket and Pocket3D

Version is 0.20 / 29177
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bmsaus4ax
Posts: 156
Joined: Sat Nov 14, 2020 9:16 pm
Location: Bargara, Queensland, Australia UTC+10

Re: Pocket inside to outside

Post by bmsaus4ax »

usul27 wrote: Sun Jun 26, 2022 5:41 am
On the top layer it just starts on the periphery :( There is a setting "Start From" that's set to center, but it doesn't seem to have any effect, the result is the same if I set his to Center or Edge.
After creating the operation , then in the Data tab, at the bottom of the list is the heading Start Point, Enter start point coordinates in the X,Y fields, and set Use Start Point true (will already be if you selected it in the operation set up)

The start coordinates can be read from the Status Bar at the bottom of the screen by hovering mouse over the inner Z-feed path line. You can nominate any value close to the desired start point, it doesn't need to be exact but should be close, the cut path will jump to the nearest valid path.
You will see this as a tool movement in the g-code as a G0 so get the start as close to the path line as you can.

Two points here;
-->X0,Y0 will not work,
-->the path will still alternate outside to inside to outside start on subsequent layers. This is a known persistent flaw in the path generation which can be overcome with a macro and Custom operations.
usul27
Posts: 3
Joined: Sat Jun 25, 2022 1:04 pm

Re: Pocket inside to outside

Post by usul27 »

While settings a start point for a single pocket might work, it won't work for a Pocket3D operation. Programming each pocket individually for a complex object doesn't seem to make much sense.
I would expect FreeCAD to do this. What's the "Center" option about? Does it have any effect?
usul27
Posts: 3
Joined: Sat Jun 25, 2022 1:04 pm

Re: Pocket inside to outside

Post by usul27 »

No one has an idea?
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