How to use CutMaterial result as new stock?

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Vinc89
Posts: 2
Joined: Fri Sep 30, 2022 11:59 am

How to use CutMaterial result as new stock?

Post by Vinc89 »

Hi there,
Im wondering if there is a way how I can use the CutMaterial result of the CAM Simulator as a new stock.
Background is that I have the following shape:
shape.png
shape.png (53.61 KiB) Viewed 1111 times
Than I start the milling with a 3mm endmill and get the following result with "stairs":
stairs.png
stairs.png (83.63 KiB) Viewed 1111 times
After that I would like to clear the stairs of the "half pipe" with a 6mm spheric mill. I dont use that one from the beginning because my CNC maschine is to small to handle 6mm milling wood.
Now I can make a 3D Pocket with the 6mm tool, but it will be milling 75% of the time just air and not the stairs.

So thats the reason why I would like to use the CutMaterial as a new stock. If there are any other possibilities Im open for any ideas.
Thanks a lot for help.

--
Vinc
chrisb
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Posts: 53919
Joined: Tue Mar 17, 2015 9:14 am

Re: How to use CutMaterial result as new stock?

Post by chrisb »

Hi and welcome to the forum!

You simply start with the endmill operation and in the same job you continue with the ball end. The simulator may not show this correctly, the "Inspect path commands" may be more helpful. Try marking the lines from the start on, and see the sequence of movements in the 3D view.
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spanner888
Posts: 326
Joined: Tue May 28, 2019 10:51 am

Re: How to use CutMaterial result as new stock?

Post by spanner888 »

Another way to view this is to consider that CNCing & thus Path workbench, is all about a sequence of cuts, and some of those, eg finishing cuts, occur "over" a previous cut.
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pathfinder
Posts: 315
Joined: Mon Oct 04, 2021 10:27 am

Re: How to use CutMaterial result as new stock?

Post by pathfinder »

Vinc89 wrote: Fri Sep 30, 2022 12:18 pm
Now I can make a 3D Pocket with the 6mm tool, but it will be milling 75% of the time just air and not the stairs.

So thats the reason why I would like to use the CutMaterial as a new stock. If there are any other possibilities Im open for any ideas.
Thanks a lot for help.

--
Vinc
Using a Ballend(--> spheric mill) and 3d Pocket isn't a good idea, because 3d Pocket doesn't recognize ballend shapes and will treat it as a regular endmill. With a simple half pipe shape, there's a way to build an object that will create a feasible ballend toolpath, but in general, it won't work properly.

3d Surface does recognize ballend shapes and has a single layer option, where it will simply follow the topology of the object (or the selected faces), so that can be used quite nicely for finishing operations (little pro tip: if you use the line or zigzag operation, you can change the angle of the lines after closing the task in the property field).
Vinc89
Posts: 2
Joined: Fri Sep 30, 2022 11:59 am

Re: How to use CutMaterial result as new stock?

Post by Vinc89 »

Thank you very much that was was I was searching for.
It was quite a mess to get OCL/3D surface running on my mac, but since its working now its exactly what I needed.

Thanks
karlnick
Posts: 54
Joined: Sat Jul 25, 2020 9:33 am

Re: How to use CutMaterial result as new stock?

Post by karlnick »

Reading the source code it seems a mesh like this usually used for FEM calculations is used to approximate cut material.

For a path in (x,y) direction sweep of sketch used for tool bit perpendicular to direction in union with rotation of sketch will probably give a better result if possible to do such a sweep. Movement in z direction is harder though for straight line it would be possible to do a sketch a new sketch from sketch use for tool bit in union with rotation of sketch will probably do the trick. Then curved in z direction it will be harder but guess it will be possible to solve if possible to rotate sketch then sweeping and switch between sketches depending z direction angle and then direction of movement change.
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