Omitting one or more sides when contouring/profiling

Here's the place for discussion related to CAM/CNC and the development of the Path module.
schnebeck
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Re: Omitting one or more sides when contouring/profiling

Postby schnebeck » Mon Oct 28, 2019 10:10 pm

chrisb wrote:
Mon Oct 28, 2019 9:53 pm
Just saw it with delight :D , but I didn't succeed in creating a partial path. Would you mind uploading your file for investigation?
You have to recalculate the adaptive op, otherwise the file would be too big.
You have to add the edges from part and stock in two passes. If you select edges from stock and part during op creation you get an error message like "use only edges from one part". Follow this advice, create the op, reopen the "basic geometry" section and add now the three edges from the stock.
Screenshot_20191028_232155.png
Screenshot_20191028_232155.png (53.92 KiB) Viewed 471 times
Here I visualize the selected edges for this op. Again, these "nearly closed" edge loops work only with adaptive op.
HTH

Thorsten

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Last edited by schnebeck on Mon Oct 28, 2019 10:45 pm, edited 3 times in total.
chrisb
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Re: Omitting one or more sides when contouring/profiling

Postby chrisb » Mon Oct 28, 2019 10:24 pm

Thanks, will have to study this.
RatonLaveur
Posts: 348
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Re: Omitting one or more sides when contouring/profiling

Postby RatonLaveur » Tue Oct 29, 2019 1:53 am

It's extremely interesting though. The request for partial based OPs is a recurring one, and at least one tool (adaptive) seems to be able to perform it, albeit with a bit of upstream work in stock creation and selection.

Often the only other recourse for partial ops is Helper Pad or a derivative use of Deburring tool.

But this raises two very promising points in my view:
1. How to facilitate/automate the method you've outlined so that it's more intuitive/robust to use.
2. How to verify what makes adaptive able to perform some tasks that Pocket or Profile can't do at the moment.
herbk
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Location: Windsbach, Bavarya (Germany)

Re: Omitting one or more sides when contouring/profiling

Postby herbk » Tue Oct 29, 2019 6:01 am

Hi,
using adaptive is possible, but produces a lot of (expensive) machining time.
Adaptive is a pocketing OP and removes all material. At most cases a countour path is sufficient because not all the unneeded material has to be made to chips... ;)
Gruß Herbert
RatonLaveur
Posts: 348
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Re: Omitting one or more sides when contouring/profiling

Postby RatonLaveur » Tue Oct 29, 2019 8:26 am

Hello Herbert,

Fully agree, but if adapative is the most able to perform partial operations then there's the choice to use adaptive. What i meant is perhaps it would be worth looking into the DNA of adaptive to see if its ability to run partials cannot be extended to profile and pocket.

Cheers,
mlampert
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Re: Omitting one or more sides when contouring/profiling

Postby mlampert » Tue Oct 29, 2019 6:06 pm

I was initially quite intrigued by the approach for adaptive's use but realised that this is probably going in the wrong direction. The limiting aspect being that there can only be one Stock object - which means one would need a separate Job for each op.

I thought there would be two approaches to this problem
* partial selection
* path limitation (dressup ?)

Partial selection is basically extend the flexibility of Engrave/Deburr to the profile ops and allow non-closed features to be selected.

Path limitation leaves the ops as they are but, in a post processing step (no pun intended) remove all Commands which go outside a certain boundary and replace them with moves to Save/ClearanceHeight and G0 to the connection point. The tricky part here is to define the boundary shape. A dressup could be quite flexible because the basic implementation could be quite simple and complex shapes can be constructed by adding multiple dressups on top of each other.
Another approach for path limitation could be similar to how currently Stock is managed - again a dressup seems to be a natural fit here.

What I like about the dressup approach is that it could be applied to any operation and does not require modification of all existing ops.
RatonLaveur
Posts: 348
Joined: Wed Mar 27, 2019 10:45 am

Re: Omitting one or more sides when contouring/profiling

Postby RatonLaveur » Tue Oct 29, 2019 9:10 pm

I think you nailed it on the head with the two points.

But i think both would need to coexist because i feel like the dressup approach would be complicated for complex profiles.

What I love about this conversation is the potential implications for PathSurface, which is what i generally need on a daily basis (currently using Siemens NX for most but not all tasks. Would love to use FC always.)

For your first point which you at first suggest is less desirable,
What if: by selecting an area, you create automatically a bounding box for the selection, a "sub stock" if you will specifically for that OP.
chrisb
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Re: Omitting one or more sides when contouring/profiling

Postby chrisb » Wed Oct 30, 2019 6:42 am

RatonLaveur wrote:
Tue Oct 29, 2019 9:10 pm
What if: by selecting an area, you create automatically a bounding box for the selection, a "sub stock" if you will specifically for that OP.
That was my idea as well. Something like a sketch which can be selected limiting the path to stay inside.
RatonLaveur
Posts: 348
Joined: Wed Mar 27, 2019 10:45 am

Re: Omitting one or more sides when contouring/profiling

Postby RatonLaveur » Wed Oct 30, 2019 9:29 pm

Yeeees. Honestly all of these suggestions are a laser user's fantasy. Granted not everyone here has a laser...
mlampert
Posts: 1363
Joined: Fri Sep 16, 2016 9:28 pm

Re: Omitting one or more sides when contouring/profiling

Postby mlampert » Sat Nov 02, 2019 3:24 am

In case somebody has some time for testing, I did a POC for the "Boundary Dressup":
https://github.com/mlampert/FreeCAD/tre ... nt-dressup
I have no idea what suitable base shapes would/could/should be so I just reused the Stock editor from Job.