[Nico_]

Hi guys,

I'm learning how to use a XY pen plotter (makeblock) with a mac os computer. Everything seems ok for straight-line drawings (G0 and G01 gcode commands). But when drawing arcs (G02 and G03), strange and unexpected circles appears frequently.

I give you a code example :
G90
G00 Z 0.0000
G00 X 96.3989 Y 102.6324


G01 Z 1.0000
G02 X 91.3737 Y 97.6917 Z 1.0000 I -157.3031 J 154.9677 F 1000.0000
G02 X 84.6144 Y 94.6524 Z 1.0000 I -7.6975 J 8.0832
G03 X 84.9893 Y 92.4134 Z 1.0000 I 0.6141 J -1.0481
G02 X 85.0722 Y 90.5042 Z 1.0000 I -0.1938 J -0.9648
G03 X 87.8963 Y 86.4377 Z 1.0000 I 3.6663 J -0.4677
G03 X 92.5175 Y 85.9352 Z 1.0000 I 4.3670 J 18.6607
G02 X 97.6347 Y 83.1403 Z 1.0000 I -0.4670 J -6.9372
G02 X 98.9512 Y 77.8592 Z 1.0000 I -5.6948 J -4.2243
G02 X 99.9766 Y 75.0199 Z 1.0000 I -6.3328 J -3.8919
G03 X 100.2899 Y 73.0513 Z 1.0000 I 62.8027 J 8.9836


where the last command line produces a circle where it must draw a tiny curve. (the code came from inkscape gcodetools)

Attachment 249544

I check my gcode with Gwizard and I cannot see the problem !

Please, answer me ! I need your help !!

[TOTALLYRC]

Make sure that your IJ mode in your cam program matches the IJ mode in your machine control software.
Mike

[Nico_]

Thanks Mike,

I thought of some trouble like that.

I tried to add a G90.1 command line on the beginning and nothing happened. But if I add G91.1, no part of the path is not well (not only the wrong-circle-part).

The machine control software is very simple and admit no arc settings....