Does Luban support Gcode G2 and G3?

Snapmaker Luban
1

Hi everybody,
i am having a hard time trying to use G2 and G3 in a selfmade GCode. It seems to read the G2 and G3 command, but ignores all G1 and G0 after those arcs.
Does Luban support G2 and G3 that at all?
Here’s the gcode:

;Header Start
;header_type: cnc
;is_rotate: false
;diameter: 35
;work_speed(mm/minute): 300
;jog_speed(mm/minute): 1500
;power(%): 0
;Header End

G90 ;Absolut
G21 ;Millimeters
G28 ;Go Home
M3 P100 ;Spindle On

G1 Z60 F306
G1 X30.0 Y10.5
G1 Z0
G2 X30.5 Y10.0 I0 J-0.5
G1 X30.5 Y6.5
G1 X35.0 Y6.5
G3 X40.5 Y12 I0 J5.5
G1 X40.5 Y23.62132
G1 X36.70335 Y27.417971
G1 X36.20267 Y27.486245
G1 X36.20267 Y27.486245
G1 X30.602029 Y28.05892
G1 X25.0 Y28.249811
G1 X19.397971 Y28.05892
G1 X13.79733 Y27.486245
G1 X13.551285 Y27.452694
G1 X8.575188 Y24.964645
G1 X7.579242 Y13.013296
G3 X9.580316 Y10.354231 I2.491364 J-0.207614
G1 X19.210493 Y8.428196
G1 X23.354102 Y10.5
G1 X30.0 Y10.5

G0 Z50.00
M5
G28

Please help!

2

G2/3 wouldn’t need luban support, it should be dependent only on the firmware.

That being said, I’ve tried to use G2/3 before (by post processing some gcode with arc welder) and the machine definitely didn’t do the right thing.

I didn’t dig into it too much, I just figured that the SM doesn’t properly support that gcode.

3

There’s an open firmware bug for G2/G3. At this time, support for these commands isn’t good enough to risk using them. Snapmaker Marlin "G3"?

2 Likes
4

This request has been forwarded to our firmware developer, @scotthuang . He also is in charge of our GitHub repository. We will make sure if we will add G3 nearly.

Sorry for the inconvenience.
Edwin

5

Hi there. Is there any update on this issue, please? I could really, REALLY do with being able to use the G2 and G3 moves as the incessant G0 Z1.00 G1 Z-1.00 F200 lift and plunge at the end of EVERY tiny arc segment is doing my nut in!

Alternatively, and other than manually editing the Gcode files, is there any way of tweaking how the backend of Luban writes the Gcode? Id like to stop it doing so many needless G0 Z++ moves - I reckon its tripling the machining time.

Thank you.

Ed.

1 Like
6

Huh, it shouldn’t be retracting between G1 segments… Is that actually how luban is slicing things?

G2/G3 should just be moving the arc segmentation down to the firmware, so I’ll not sure how much benefit it would provide, especially if the processor on the SM is slower, it might even be better to be streaming gcode segments instead of the controller trying to compute the segments on the fly (but there’s other benefits to doing that processing in the firmware layer).

7

This is in 3axis CNC, and it is Gcode built by Luban. I use Solidworks CAM and I can’t get it to post- without using G2/3 moves. I have got a bit of software that converts arcs to lines, but it’s all a bit of a ballsache using several bits of software. I get that Luban will never be DelCAM, but I’d like to have a LOT more configurability on hand without resorting to rebuilding it all from GitHub!

The powerful search/replace functionality of notepad++ is beginning to make it a go-to editor…

1 Like