G2-G3 arc moves feed not interpreted correctly in CNC mode

Hi, thanks for the great work and products.

I have the Snapmaker 2.0 A250 on a 3 axis setup, no rotary module / 4th axis.
Recentely I went into optimization of my pathes (feed, depth of cut, width of cut) for best speed / quality ratio, and noticed Feed command seemed to not be interpreted correclty on G2 G3 moves , even though it seems a valid argument on the Snapmaker doc (linked before). Specifically, they seemed much slower than the G1 moves even though i set the same feed for both, specified at each line (just to be sure).

My firmware version is Snapmaker2_V1.14.1

Has this behavior already been reported ? If so, do you plan to investigate / fix it ?
Thanks !
And happy neaw year celebrations.

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From another post , it appears that is the current behavior, and there is an issue open to address it.

Ok thanks, interesting !
From a quick search, I’ve seen from the GH marlin repository (because from what I understood, the G2/G3 issue or late implementation comes from the fact marlin had some issue with it and just replaced it by G1 interpolations), an issue, that seems to tackle the slow G2/G3. A matter of seg_length that has to be set to 0.0 it seems…
Source : [BUG] G02/G03 commands execution speed issues
I wanted to bring the info here in case @scotthuang was not already aware of this.Sorry for the disturbance if it is already the case.
Have a great week.

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Had a major failure this morning with some errant G3 commands and carved up some of the metal clips holding down a nice piece of red oak on my A350. I used VCarve 11 and the Snapmaker post-processer to produce a .cnc file, which when compared to a gcode post-processor clearly has incorrect G3 commands. Now that I know about https://ncviewer.com I can catch these ahead of time, but either the post-processor gets fixed or this workflow just became a massive copy and paste exercise for each file. Happy to share more about this disaster if it helps get the Aspire VCarve post-processor fixed!

Did some test today with the trial version of VCarve 11. Had the same problems. Finally i got a working cnc file by commenting out the G2 and G3 parts (arc moves) in the .pp postprocessor file. Seems that G2 and G3 commands do not work properly.

I was able to debug the .cnc file by removing some of the linework to simplify the design, and also by deleting a few remaining G3 commands - had quite a few G2 arcs that did work okay.

Going forward I will have to be vigilant checking files I prep in VCarve 11 - it is such good software; love it!