Material remains in pocket operation when step over > 50%

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hans
Posts: 114
Joined: Sun Feb 02, 2020 8:26 pm

Re: Material remains in pocket operation when step over > 50%

Post by hans »

Les Newell wrote: Thu Jan 07, 2021 3:18 pm Are you running linux? If so you can run the Windows version using Wine. Install Wine using your package manager then download and install Dev just like you would on Windows. Wine has a few quirks but it works pretty well. The Linux version is Dev but it only gets updated occasionally, at points where I think Dev is pretty stable. The next update is due around mid February.
Unfortunately this didn't really work on my machine :(

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Les Newell
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Re: Material remains in pocket operation when step over > 50%

Post by Les Newell »

The next release (due out in a few days) will have a new zigzag pocket that doesn't do the backup moves. With some careful optimisation of the tool paths I've made it at least as fast as the old zigzag pocket while also leaving a smooth wall to the pocket. If you use ramping it will be faster. Usually when it has to do a reposition move it will aim for an area nearby that has already been cleared so it can plunge down to depth at rapid rate rather than doing a ramp.
hans
Posts: 114
Joined: Sun Feb 02, 2020 8:26 pm

Re: Material remains in pocket operation when step over > 50%

Post by hans »

Oh I missed this post. No I understand your recent question regarding the current zig zag algorithm. Sorry.

Very nice what you have done! Even faster than the zig zag with backward moves in most cases.
What I don't really understand is that it should be even faster on rectangular pockets. In my opinion it have two sides more to travel...
I just was thinking if we could let the zig zag with backward moves available as an option. Because it has also it right to exist.
But if it brings no speed advantage... I m going to check that on the real mill!

While comparing zig zag 2 with and without cleaning pass, I made some weird observations in time calculating.
I think the job time without cleaning pass can't be twice the time with cleaning pass.
I just post this because it may is related to the general time calculation.

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Last but not least: I noticed that the first step over doesn't exactly meet the given step over value. I had a 6mm mill with 80% step over.
I don't think that that is going to be a problem, because its so little, but only to be mentioned. And I think you already know this and that's may the reason why the step over is limited to 95% ;-)
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Les Newell
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Re: Material remains in pocket operation when step over > 50%

Post by Les Newell »

hans wrote: Tue Mar 02, 2021 8:20 am I just was thinking if we could let the zig zag with backward moves available as an option. Because it has also it right to exist.
But if it brings no speed advantage... I m going to check that on the real mill!
I'm not sure yet if I will keep the backup moves. The code does allow for this but it's extra documentation and maintenence overhead. I need to do some more testing to see if there are any real world advantages to using it.
While comparing zig zag 2 with and without cleaning pass, I made some weird observations in time calculating.
Yes, that does look wrong. Shorter cut and rapid distances but much longer cut time. That's not right. I need to run some more tests.
Last but not least: I noticed that the first step over doesn't exactly meet the given step over value.
It varies depending on the geometry of the part. To generate the paths I work out the overall extents of the part then draw a series of horizontal lines starting at the bottom. I then remove any parts of the lines that are not over the pocket, which leaves the horizontal component of the zigzag. For angled zigzags I rotate the shapes so so that the lines are horizontal, calculate the tool paths then rotate back.

The 95% is pretty arbitrary. If you tried to run 100% you'd probably end up with thin ridges on the floor of the pocket so I limited it to just under 100%.
hans
Posts: 114
Joined: Sun Feb 02, 2020 8:26 pm

Re: Material remains in pocket operation when step over > 50%

Post by hans »

Les Newell wrote: Tue Mar 02, 2021 11:14 am The 95% is pretty arbitrary. If you tried to run 100% you'd probably end up with thin ridges on the floor of the pocket so I limited it to just under 100%.
Yes of course I would never use 100% step over...
hans
Posts: 114
Joined: Sun Feb 02, 2020 8:26 pm

Re: Material remains in pocket operation when step over > 50%

Post by hans »

Les Newell wrote: Tue Mar 02, 2021 11:14 am
hans wrote: Tue Mar 02, 2021 8:20 am While comparing zig zag 2 with and without cleaning pass, I made some weird observations in time calculating.
Yes, that does look wrong. Shorter cut and rapid distances but much longer cut time. That's not right. I need to run some more tests.
Ahh please forget that. It seems that I accidentally had the path rule enabled with some big minimal values for testing. I'm sorry.
I could not reproduce this now. I hope you haven't already spent time on it
hans
Posts: 114
Joined: Sun Feb 02, 2020 8:26 pm

Re: Material remains in pocket operation when step over > 50%

Post by hans »

I did some speed testing comparing the new zigzag and the zigzag 2 without cleaning pass.
On rectangular contours the speed is almost the same as one can imagine.
But the bigger profit is on complex contours where the backward moves takes more time.

Not to mention zigzag 2 with cleaning pass. That would need much more time to achieve the same surface quality like the new zigzag.

What I want to say with that: I'm really happy with the new zigzag algorithm. Great job!
So there is no need for zigzag2 in my opinion :-)
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