[solved] Interpolate arcs with line segments

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JTI
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Joined: Fri Sep 24, 2021 12:06 am

[solved] Interpolate arcs with line segments

Post by JTI » Fri Sep 24, 2021 12:51 am

Hello,
I try to use the "Interpolate arcs with line segments" in the CAM configuration, but the generated tool path around a simple circle is only half a circle. I have tried this with different postprocessors without any luck. Did I miss a setting to get a full circular toolpath?

Thanks in advance
Last edited by JTI on Fri Oct 01, 2021 10:54 pm, edited 3 times in total.

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andrew
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Re: Interpolate arcs with line segments

Post by andrew » Fri Sep 24, 2021 9:33 am

I cannot reproduce this problem. Please attach your DXF file and the output file (e.g. .nc) and indicate which post processor you are using.

JTI
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Joined: Fri Sep 24, 2021 12:06 am

Re: Interpolate arcs with line segments

Post by JTI » Sat Sep 25, 2021 2:47 pm

Hello Andrew,
please find attached the following files:

circle.dxf - source file
Grbl_EASEL_MM.js - my modified postprocessor file (no line numbers)
LinInterpolationIsOff.nc - how the tool path should look like
LinInterpolationIsOn.nc - how the tool path looks if "interpolate arcs with lines" is switched on
CAM Config.jpg - screenshot of CAM Configuration.

Thanks for looking into this.
Attachments
CAM Config.JPG
CAM Config.JPG (141.3 KiB) Viewed 9069 times
LinInterpolationIsOn.nc
(6.88 KiB) Downloaded 355 times
LinInterpolationIsOff.nc
(152 Bytes) Downloaded 358 times
Grbl_EASEL_MM.js
(1.17 KiB) Downloaded 372 times
Circle.dxf
(117.03 KiB) Downloaded 357 times

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andrew
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Re: Interpolate arcs with line segments

Post by andrew » Mon Sep 27, 2021 9:53 am

Thanks. I can confirm this is a bug.

As a workaround, you can add this to your post processor:

Code: Select all

Grbl_EASEL_MM.prototype.getArcInterpolation = function() {
    return Grbl.prototype.getArcInterpolation.call(this) && ((this.checkContext("CamOffset") && this.outputOffsetPath) || (!this.checkContext("CamOffset") && !this.outputOffsetPath));
};
This fix will also be included in the next QCAD/CAM release.

JTI
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Posts: 8
Joined: Fri Sep 24, 2021 12:06 am

Re: Interpolate arcs with line segments

Post by JTI » Mon Sep 27, 2021 6:49 pm

Thank you Andrew.

Ich werde den work around heute ausprobieren.
Freut mich, dass ich helfen konnte.

JTI
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Posts: 8
Joined: Fri Sep 24, 2021 12:06 am

Re: Interpolate arcs with line segments

Post by JTI » Thu Sep 30, 2021 11:46 pm

Hello Andrew,
the work around does not seam to work. The tool path looks the same as before.

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andrew
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Re: Interpolate arcs with line segments

Post by andrew » Fri Oct 01, 2021 7:21 am

Please attach your modified post processor file, thanks.

JTI
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Joined: Fri Sep 24, 2021 12:06 am

Re: Interpolate arcs with line segments

Post by JTI » Fri Oct 01, 2021 7:57 pm

Sorry I missed that.
Attachments
Grbl_EASEL_MM.js
(1.41 KiB) Downloaded 370 times

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andrew
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Re: Interpolate arcs with line segments

Post by andrew » Fri Oct 01, 2021 9:18 pm

Please move the new function (Grbl_EASEL_MM.prototype.getArcInterpolation = function ...) to the end of the file, otherwise the line

Code: Select all

Grbl_EASEL_MM.prototype = new Grbl();
assigns a new prototype and deletes your function getArcInterpolation in the process.
Attachments
Grbl_EASEL_MM.js
(1.41 KiB) Downloaded 436 times

JTI
Newbie Member
Posts: 8
Joined: Fri Sep 24, 2021 12:06 am

Re: Interpolate arcs with line segments

Post by JTI » Fri Oct 01, 2021 9:55 pm

Thank you very much Andrew. This time it worked perfectly.

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