Facets on arcs

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Skyler
Posts: 9
Joined: Fri Oct 30, 2020 10:25 am

Facets on arcs

Post by Skyler » Wed Dec 23, 2020 8:00 pm

I'm experiencing many small facets on 2d arc moves, instead of smooth curves. I've tried max deviation values from 0.01" to 0.0001" and get facets with all of the values I've tried. How can I minimize or eliminate this issue?

Thanks!

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Doug
Posts: 188
Joined: Fri Feb 02, 2018 4:56 pm

Re: Facets on arcs

Post by Doug » Wed Dec 23, 2020 8:19 pm

At the lowest level, arcs are converted to a series of straight lines. The lines should become shorter and shorter as you decrease 'max-deviation', they they will never become a perfect arc.

Skyler
Posts: 9
Joined: Fri Oct 30, 2020 10:25 am

Re: Facets on arcs

Post by Skyler » Wed Jan 06, 2021 7:34 pm

I've tried setting the max-deviation to 0.0000000001", but I still get very visible facets on arcs (segments around 0.04" long)

What can I do to improve this?

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Doug
Posts: 188
Joined: Fri Feb 02, 2018 4:56 pm

Re: Facets on arcs

Post by Doug » Tue Jan 12, 2021 6:46 pm

If you post your gcode, I can take a look at it.

Skyler
Posts: 9
Joined: Fri Oct 30, 2020 10:25 am

Re: Facets on arcs

Post by Skyler » Wed Jan 13, 2021 2:58 am

Here is the relavent part of the program, thanks for your help!

(2D CONTOUR2 2)
N4360 G0 X1.1436 Y0.4075
N4365 Z0.7875
N4370 Z0.3875
N4375 G1 Z0.0125 F1.3
N4380 G18 G3 X1.1311 Z0. I-0.0125 K0. F5.2
N4385 G1 X1.1186
N4390 G17 G3 X1.1061 Y0.395 I0. J-0.0125
N4395 G1 Y0.3013
N4400 G2 X1.0436 Y0.2387 I-0.0625 J0.
N4405 G1 X0.9797
N4410 G3 X0.7822 Y0.1421 I0. J-0.25
N4415 G2 X0.1306 Y0.6479 I-0.3258 J0.2529
N4420 X0.7822 I0.3258 J-0.2529
N4425 G3 X0.9797 Y0.5512 I0.1975 J0.1533
N4430 G1 X1.0436
N4435 G2 X1.1061 Y0.4887 I0. J-0.0625
N4440 G1 Y0.3013
N4445 G2 X1.0436 Y0.2387 I-0.0625 J0.
N4450 G1 X0.9797
N4455 G3 X0.7822 Y0.1421 I0. J-0.25
N4460 G2 X0.1306 Y0.6479 I-0.3258 J0.2529
N4465 X0.7822 I0.3258 J-0.2529
N4470 G3 X0.9797 Y0.5512 I0.1975 J0.1533
N4475 G1 X1.0436
N4480 G2 X1.1061 Y0.4887 I0. J-0.0625
N4485 G1 Y0.395
N4490 G3 X1.1186 Y0.3825 I0.0125 J0.
N4495 G1 X1.1311
N4500 G18 G2 X1.1436 Z0.0125 I0. K0.0125
N4505 G0 Z0.7875
N4510 G17
N4515 G53 G0 Z0.
N4520 M30
%

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Doug
Posts: 188
Joined: Fri Feb 02, 2018 4:56 pm

Re: Facets on arcs

Post by Doug » Fri Jan 22, 2021 2:22 pm

It turns out that there is a parameter in the planner software that specifies the allowable error when cutting arcs. Up until now, this parameter has not been accessible to the users. The next release of software (0.4.16) will expose this parameter to the user. Current testing has demonstrated that this fixes the problem.

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