How to generate a path that I can envision but FreeCAT can not.

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PapaAtHome
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Joined: Mon Dec 31, 2018 6:45 pm

Re: How to generate a path that I can envision but FreeCAT can not.

Post by PapaAtHome »

I will do a small series of quick, short, messages with my results so far.
The fixed model is already uploaded in a previous message and I will not repeat it here.
I keep the fixed model unchanged, not correcting the overshoot of the diamond at the four corners.

This (first) message includes the parameterised model. Again, I will not repeat that in every message.
The parameterised model has no overshoot, it has a perfect match of the diamond corners on the circle and square.
The advantage of using a spreadsheet with parameters and matching up points in the design. :)

On the inner circle pocket I got a result which is different between the two models and I cannot explain it.



First, on the 'fixed model' (unchanged, available in a previous upload) I get, what seems to me, an incomplete path.
fixed-inner pocket.PNG
fixed-inner pocket.PNG (70.05 KiB) Viewed 600 times


On the parameterised model (see attached project) I do not get the same result. And I don't know why.
param-inner pocket.PNG
param-inner pocket.PNG (158.8 KiB) Viewed 600 times
Attachments
Square-Circle-Diamond.v0.19.FCStd
(51.54 KiB) Downloaded 17 times
Kind regards, Andre.
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PapaAtHome
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Re: How to generate a path that I can envision but FreeCAT can not.

Post by PapaAtHome »

What I want to archieve with the inner pocket is to only cut out one circle and not milling away the total of the pocket.
Grounds for this:
- If I cut out the circle it becomes detachted from the rest of the model, no need to do more.
- It saves time!

This is my (naive) idea of creating a path.
"I want to do an operation on a surface (or edge) and it is sufficient to select that surface (or edge)."
I assume that the bit is always touching the surface I selected. If the tool is not somehow touching the surface then it is doing something that is not part of the operation I want.

With my idea of a path there are two parts of the bit that counts, the tip and the side. For some selections only the tip can touch the surface and for some other selections only the side can touch the surface.

Here is an image of what I want. (Done on the fixed model, the picture shows what I want but the details are not matching up in total with my idea).
surface operation.PNG
surface operation.PNG (56.73 KiB) Viewed 593 times
The surface has a Z component and only the side of the bit can touch it.
This makes some of the patterns 'stange'. (Just proving that my idea of path operations is indeed naive and incomplete.)
What does 'line', 'grid' or 'triangle' mean for the surface I have selected?
Also, availabl in some operations but not in this example, what is the meaning of 'inside' and 'outside'?
The above image was produces with a 'Pocket mode' operation.
Again, it is difficult to match this operation with my idea of surface operation.

I guess that a 'Facing operation' is more apropriate here. (As in 'an operation on the facing that is selected' ).
But what is the meaning of all the patterns for the selected facing?
Also, none of the patterns stick to the surface only, all work on the pocket.
facing operation.png
facing operation.png (55.58 KiB) Viewed 593 times
Clearly, I have the wrong ideas about path operations.
Can anyboy explain, in short, how to look at this?
Kind regards, Andre.
herbk
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Location: Windsbach, Bavarya (Germany)

Re: How to generate a path that I can envision but FreeCAT can not.

Post by herbk »

Hi Andre,

you are using the option "Spiral" for path creation. If i remember right, Spiral is a bit bugy...

If you want to cut it out only (not remove the whole area), use Contour by Edge or Contour by Face instead of the Pocket OP. At the last 0.19 this contour OPs are combined at Profile entire Model. Just select the upper edge of the hole and click Profile entire Model.
Profile entire Modell.
All Pocket OPs of FC Path are made to remove all material.
Gruß Herbert
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PapaAtHome
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Re: How to generate a path that I can envision but FreeCAT can not.

Post by PapaAtHome »

On completely circumfencing the diamond and circle shape.

Done some testing on the parameterised model and it realy is easy and simple!
When you realise that you can limit the final depth. :mrgreen:

Here is an unlimited example, cutting all the way through the circle and square.
Profile unlimited.PNG
Profile unlimited.PNG (41.68 KiB) Viewed 582 times

And here is the limited case.
Profile limited.PNG
Profile limited.PNG (35.28 KiB) Viewed 582 times

That is one problem down and I learned a new trick. :P
Kind regards, Andre.
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PapaAtHome
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Re: How to generate a path that I can envision but FreeCAT can not.

Post by PapaAtHome »

herbk wrote: Sun May 17, 2020 11:32 am Hi Andre,

you are using the option "Spiral" for path creation. If i remember right, Spiral is a bit bugy...

If you want to cut it out only (not remove the whole area), use Contour by Edge or Contour by Face instead of the Pocket OP. At the last 0.19 this contour OPs are combined at Profile entire Model. Just select the upper edge of the hole and click Profile entire Model.
Profile entire Modell.
All Pocket OPs of FC Path are made to remove all material.
As I'm working with the latest version of 0.19, this is a quick test.
And it works as you suggested.
Contour.PNG
Contour.PNG (73.28 KiB) Viewed 579 times

Second problem solved. And I learned another trick, never stop trying.
But I also feel like I should have asked this questiong a long time before.
With a few suggestions my problems are solved in less than a day while I've been struggling with it for month after month.

Thank you all. :D
Kind regards, Andre.
chrisb
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Re: How to generate a path that I can envision but FreeCAT can not.

Post by chrisb »

Here is another proposal for your question 2:
If I reduce the radius of the cylinder by 1/100 (1/1000 would work probably too) I can create easyly a circle around diamond and cylinder using a profile operation. File is attached.
Snip macro screenshot-63a28f.png
Snip macro screenshot-63a28f.png (19.37 KiB) Viewed 556 times
Attachments
Square-Circle-Diamond_cb.FCStd
(25.77 KiB) Downloaded 21 times
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PapaAtHome
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Re: How to generate a path that I can envision but FreeCAT can not.

Post by PapaAtHome »

chrisb wrote: Sun May 17, 2020 8:39 pm Here is another proposal for your question 2:
If I reduce the radius of the cylinder by 1/100 (1/1000 would work probably too) I can create easyly a circle around diamond and cylinder using a profile operation. File is attached.Snip macro screenshot-63a28f.png
I can see your point, with the reduction the cylinder is just a fraction smaller than the square and so is the diamond to the cylinder.
If the fraction is less than the machine precission you would not notice the differencent at all. Nice. 8-)
reduction.PNG
reduction.PNG (61.8 KiB) Viewed 537 times

With the parameterised version I have a perfect match for both cylinder and diamond (to the square) and no dificulties in creatting a path around it. But I have to look out for the depth of the path(s). (I did not check it that is a requirement in your solution.)
Match.PNG
Match.PNG (125.06 KiB) Viewed 537 times

Thanks for the idea. To me it looks like there is more than one solution to the problem. ;)
Kind regards, Andre.
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