Sheetcam to GRBL

1

Hi there,
I’ve got my XCarve a few weeks now and it’s working fine. I’m also trying to cut leather with a dragknife, so I bought a Donek D4 and the Sheetcam software. So far it’s going good, but I can’t send the GRBL code to the XCarve. I’ve tried A Universal G-Code sender and Chilipepr. I think the issue is within the machine settings in Sheetcam. Does anyone have experience which post processor to choose in Sheetcam?
Thanks for your help,

Tim

2

Tim, did you ever get anywhere with this because I am having the same issue?

4

I am having exactly the same problem with a Donek D4, SheetCam and my X-Carve.

Les at SheetCam recommended that the ‘Minimum G-code’ post-processor would work best. I’m attempting the Donek recommended test of moving in a circle with a radius equivalent to the offset of the knife. But when I use the G-code generated by that post-processor to attempt a circle, the tool is moved in the Z axis to the cut depth and immediately moved back to travel height without any X or Z movement.

I’ve experimented with this manually and cannot get a G02 of G03 to execute without the X and Y values specified. It doesn’t work correctly when I do so, it executes a quarter arc then travels in a straight line, but it won’t work at all without them.

Here is the G-code generated by the Minimum G-code postprocessor:
N0010 G20
N0020 M6 T1
N0030 G00 Z0.2900
N0040 G00 X2.9280 Y4.4259
N0050 G00 Z0.0500
N0060 G02 I-0.1780 J-0.1759 F300.0
N0070 G00 Z0.2900
N0080 M05
N0090 M30

Trying other post processors, I noted that the EMC post writes the G02 line as:
N0140 G02 X2.9280 Y4.4259 I-0.1780 J-0.1759 F300.0

Unfortunately, this also drops the tool, touches and retracts with no X or Y movement.

I tried the same thing in VCarve Pro and discovered that the X-Carve post processor for Vectric doesn’t use G02 or G03 at all, it does the same thing as the ‘Minimum G-code no arcs’ post processor in SheetCam.

So.

  1. Is there any evidence that the X-Carve (GRBL current version) will execute a full circle using G02 or G03?
  2. Can anyone provide working X-Carve G-code using G02 or G03 that will move to X20, Y20 and make a circle at Z0 with a diameter of 9.042 (all in mm)

Thanks.

5

Got it. Forget the move to X20, Y20. This will execute a clockwise circle at X0 Y0 (easier to do repeatedly.)

G21
G00 Z4
G00 X0 Y0
G00 Z1.5
G02 X0 Y0 I4.5212 J0 F300
G00 Z4
G00 X0 Y0

To test the Donek Dragknife with that G-code, aim the blade as if it were about to cut in the X- direction. Any other position will not make a circle. Change the I value to represent the offset you’d like to test. I’ve set this up in mm, change the G21 to G20 and use inches if desired.

Some variants of G-Code (apparently not GRBL,) accept a P command on the G02/G03 line that defines repetitions. That would be nice, but doesn’t seem to work.

–Tim
(cross posting to the Donek board.)

6

Hey Guys,
So i need to cut a large volume of foam board and i have been tossing around the idea of buying a d4 done drag knife and sheet cam. from your experiences do you think this is a good idea? Also I’m new to G-code so i have a pretty big learning curve.

Idea?
If i am just making circles would i be able to just use Easel with the D4 drag knife?

7

Hi, guys!
Can anyone that has been able to solve this give us a solution?

  1. What post processor must be used in Sheetcam?
  2. What software must be used to control the x-carve? Grbl, easel or universal g-code sender?

Thanks to anyone that is able to help!