How to machine open / extended pockets?

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sebste
Posts: 25
Joined: Tue Sep 01, 2015 9:23 am

How to machine open / extended pockets?

Post by sebste »

Hi Folks!
I am having a hard time trying to find a solution here. I want to machine a Pocket with two open sidewalls. I use 2D adaptive clearing for that, but I cant find a way to tell Path to break through the sidewalls. It is hard to explain, so I attach a picture.
PATHOpenPockets.png
PATHOpenPockets.png (301.66 KiB) Viewed 1946 times
Any Ideas?

Another Issue, sort of the same nature: How would I attempt to face off an outside surface to remove, say just 1mm of extra stock on the left side of the part?

Thanks in advance,
Sebastian
chrisb
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Re: How to machine open / extended pockets?

Post by chrisb »

Currently you have to use a dogbone dressup.

It is still a weak point: you cannot mill with half of the cutter along the border.
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sebste
Posts: 25
Joined: Tue Sep 01, 2015 9:23 am

Re: How to machine open / extended pockets?

Post by sebste »

Thank you for the answer, chrisb. Dogbones do not seem to work with 2D adaptive, right?
mlampert
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Re: How to machine open / extended pockets?

Post by mlampert »

We have a change for this coming soon. We were waiting for 0.19 to open up and the current backlog of PRs to clear a bit - please stay tuned as the maintainers work their way through the existing issues. Since this is a long standing feature request I'll announce it once the PR is posted.

Note that the change is for Pocket, not for Adaptive.
pauluzs
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Joined: Wed Feb 27, 2019 7:48 pm
Location: Netherlands

Re: How to machine open / extended pockets?

Post by pauluzs »

sebste wrote: Wed Mar 20, 2019 3:46 pm Any Ideas?
Do you mind including that file for testing?
sebste
Posts: 25
Joined: Tue Sep 01, 2015 9:23 am

Re: How to machine open / extended pockets?

Post by sebste »

Do you mind including that file for testing?
Not at all.
AL_BearingBlock125.FCStd
(759.78 KiB) Downloaded 47 times
Note that the change is for Pocket, not for Adaptive.
Do you think it is tough to implement for Adaptive, as well? I need to dig though the sourcecode, again. It has been a while since I touched it last time.
Where would I find infos on the upcomming changes - just to be curious?
schnebeck
Posts: 130
Joined: Thu Jun 22, 2017 8:04 pm

Re: How to machine open / extended pockets?

Post by schnebeck »

You can try something like this:
Screenshot_20190320_221902.png
Screenshot_20190320_221902.png (83.07 KiB) Viewed 1881 times
This is made as a combination of dogbone and helix dressup-action. I had to change the process direction to ccw to get valid T-shapes.

Another way is to use adaptive clearing outside:
Screenshot_20190320_222313.png
Screenshot_20190320_222313.png (105.1 KiB) Viewed 1881 times
This is interesting if you also have to profile your main contour.

HTH

Thorsten
Attachments
Dressup-action.FCStd
(202.12 KiB) Downloaded 61 times
sebste
Posts: 25
Joined: Tue Sep 01, 2015 9:23 am

Re: How to machine open / extended pockets?

Post by sebste »

Thanks, Thorsten!
That is sort of close to what I need. There is a special dificulty with this part, though. The Operation is somewhat of a combination of profiling and pocket. What makes it tricky, is, that there is no possibility to define toolpaths by vertical faces. This would allow to machine partial profiles by trating them similar to a pocket, but just without a bottom face (Or have it defined by selected edges without the need to close the contour) This is also helpful, if you just want to plane one side face without going around the whole part profile (sometimes it is not needed and there might be a fixture or a vise in a the way). I am curious what the changes to pocket might bring...
schnebeck
Posts: 130
Joined: Thu Jun 22, 2017 8:04 pm

Re: How to machine open / extended pockets?

Post by schnebeck »

Not that complex ;-)
Screenshot_20190321_000141.png
Screenshot_20190321_000141.png (131.76 KiB) Viewed 1856 times
For clamping I would use the Bluetape-Superglue-method. I have good result using this
https://www.youtube.com/watch?v=r6DCvtcU8_M

HTH

Thorsten

EDIT:
Had to change the solid with its step import to make file shorter
Attachments
AL_BearingBlock125_Adaptive.FCStd
(943.83 KiB) Downloaded 52 times
mlampert
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Joined: Fri Sep 16, 2016 9:28 pm

Re: How to machine open / extended pockets?

Post by mlampert »

sebste wrote: Wed Mar 20, 2019 8:57 pm Do you think it is tough to implement for Adaptive, as well? I need to dig though the sourcecode, again. It has been a while since I touched it last time.
Where would I find infos on the upcomming changes - just to be curious?
The change is in this branch. The main purpose, other than providing the functionality is to figure out if the UI works, if it's usable.

I am not familiar with the Adaptive code base, have not played around with that - strictly due to time constraints (and the fact that my CNC doesn't perform well enough for adaptive).
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