# Possible bug in G3 (arc) command **URL:** \ **Category:** General Discussion\ **Created:** [April 2, 2023, 3:45pm UTC](https://klipper.discourse.group/t/possible-bug-in-g3-arc-command/7611 "2023-04-02T15:45:01Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![NameOfTheDragon](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/nameofthedragon/32/4860_2.png) [@NameOfTheDragon](https://klipper.discourse.group/u/NameOfTheDragon)\ **Post date:** [April 2, 2023, 3:45pm UTC](https://klipper.discourse.group/t/possible-bug-in-g3-arc-command/7611/1 "2023-04-02T15:45:01Z")
Dear devs, I have uncovered what appears to be a repeatable bug in the G3 (arc) command. I have a print that stops every time, with log entry “Internal error in command: G3”. The gcode file has been post-processed by Arc Welder but some slicers are now incorporating arc generation directly so this might be a latent bug that is just now getting uncovered. I have a log file and gcode file but nowhere to upload them… it doesn’t seem to be possible to create issues on GitHub against Klipper. How would you suggest we proceed? Best regards, Tim Long ---
**Author:** ![EddyMI3D](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/eddymi3d/32/1981_2.png) [@EddyMI3D](https://klipper.discourse.group/u/EddyMI3D)\ **Post date:** [April 2, 2023, 3:59pm UTC](https://klipper.discourse.group/t/possible-bug-in-g3-arc-command/7611/2 "2023-04-02T15:59:40Z")
Hello @NameOfTheDragon ! > [@NameOfTheDragon](#): > > “Internal error in command: G3” Would be interesting to know what G3 command was sent that caused the error. ---
**Author:** ![hcet14](https://avatars.discourse-cdn.com/v4/letter/h/ecd19e/32.png) [@hcet14](https://klipper.discourse.group/u/hcet14)\ **Post date:** [April 2, 2023, 4:09pm UTC](https://klipper.discourse.group/t/possible-bug-in-g3-arc-command/7611/3 "2023-04-02T16:09:17Z")
> [@NameOfTheDragon](#): > > I have a log file and gcode file but nowhere to upload them… it doesn’t seem to be possible to create issues on GitHub against Klipper. It’s a little different opening an issue concerning Klipper than usual on Github [Contact - Klipper documentation](https://www.klipper3d.org/Contact.html#i-found-a-bug-in-the-klipper-software) Good luck, hcet14 ---
**Author:** ![NameOfTheDragon](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/nameofthedragon/32/4860_2.png) [@NameOfTheDragon](https://klipper.discourse.group/u/NameOfTheDragon)\ **Post date:** [April 2, 2023, 8:33pm UTC](https://klipper.discourse.group/t/possible-bug-in-g3-arc-command/7611/4 "2023-04-02T20:33:18Z")
This looks to be the offending line… ```auto Upcoming (2524913): u'G3 X210.727 Y214.978 I-6.478 J18.383 E2.91982; perimeter\nG1 X210.326 Y214.953 F30000 ; move to first perimeter point (minimum ac' ``` ---
**Author:** ![NameOfTheDragon](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/nameofthedragon/32/4860_2.png) [@NameOfTheDragon](https://klipper.discourse.group/u/NameOfTheDragon)\ **Post date:** [April 2, 2023, 8:36pm UTC](https://klipper.discourse.group/t/possible-bug-in-g3-arc-command/7611/5 "2023-04-02T20:36:55Z")
Too many instructions, TL;DR - I slipped into a coma reading them. I think I’ll just let someone else report it. Thanks for the heads-up. ---
**Author:** ![Sineos](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/sineos/32/18_2.png) [@Sineos](https://klipper.discourse.group/u/Sineos)\ **Post date:** [April 2, 2023, 8:38pm UTC](https://klipper.discourse.group/t/possible-bug-in-g3-arc-command/7611/6 "2023-04-02T20:38:04Z")
Upload a klippy.log and a sliced gcode file here. Zip them if too big ---
**Author:** ![NameOfTheDragon](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/nameofthedragon/32/4860_2.png) [@NameOfTheDragon](https://klipper.discourse.group/u/NameOfTheDragon)\ **Post date:** [April 2, 2023, 10:21pm UTC](https://klipper.discourse.group/t/possible-bug-in-g3-arc-command/7611/7 "2023-04-02T22:21:16Z")
[G3-issue-klippy.zip](https://klipper.discourse.group/uploads/short-url/zAF54ldDNOIeXkhXeLWaDtq2m7E.zip) (5.7 MB) Ah, I had missed the upload button, I’m used to seeing a paperclip icon and didn’t register the upload icon. OK, here they are… Cheers, Tim Long ---
**Author:** ![Sineos](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/sineos/32/18_2.png) [@Sineos](https://klipper.discourse.group/u/Sineos)\ **Post date:** [April 3, 2023, 7:18am UTC](https://klipper.discourse.group/t/possible-bug-in-g3-arc-command/7611/8 "2023-04-03T07:18:17Z")
Your issue is not related to G3. In fact the error message is [Timer too close](https://klipper.discourse.group/t/timer-too-close/6634). The other errors are consequential errors. When checking a klippy.log always start at the bottom and work your way up until you find the first error ---
**Author:** ![EddyMI3D](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/eddymi3d/32/1981_2.png) [@EddyMI3D](https://klipper.discourse.group/u/EddyMI3D)\ **Post date:** [December 10, 2025, 1:43pm UTC](https://klipper.discourse.group/t/possible-bug-in-g3-arc-command/7611/9 "2025-12-10T13:43:59Z")