# Newbie Coordinate systems confusion

2 min read

I’m using the following:

Grbl 1.1h

CNC 3 board

Grbl Panel 1.0.9.18

Solidworks 2021

I’ve gotten to the point where I can use the Home Cycle button to zero the machine using 3 endstops and offset all of them 6.35mm. The values say -6.35. When I go to make a simple test part (a 200mm x 200mm square) so I can (re)adjust the X/Y/Z step/mm values, it always wants to cut in the nonexistent positive portion of the workspace.

Is it ‘standard’ to have the workspace be all negative?

I’ve noticed that if I ‘zero’ the machine in the opposite corner of where the (0,0) is that I can sometimes cut a part, but it doesn’t seem right. By ‘zeroing’ the machine I just reset the Arduino the 3 smaller sized numbers are (0,0,0) when I reconnect.

I’ve also tried changing the coordinate system in Solidworks, but it never changes anything…

Using the endstops, should I be able to just start cutting the following the sample gcode?

`N1 G20`

N2 (1/4 EM CRB 2FL 3/4 LOC)

N3 G91 G28 X0 Y0 Z0

N4 T01 M06

N5 S12000 M03

```
N6 ( Contour Mill1 )
```

N7 G90 G54 G00 X-1.3677 Y-.3102

N8 G43 Z.1 H01 M08

N9 G01 Z-.125 F16.2

N10 G41 D21 X-1.3677 Y-.4402 F48.6

N11 G17 G03 X-1.375 Y-.4579 I.0177 J-.0177

N12 G01 Y-1.875 F64.8

N13 X1.375

N14 Y.9378

N15 X.0679 Y1.9264

N16 X-1.375 Y.9343

N17 Y-.4829

N18 G03 X-1.3677 Y-.5006 I.025 J0

N19 G40 G01 Y-.6306

N20 G00 Z.1

N21 X-1.3723 Y-.6282

N22 G01 Z-.125 F16.2

N23 G41 D21 X-1.3723 Y-.4982 F48.6

N24 G03 X-1.365 Y-.4805 I-.0177 J.0177

N25 G01 Y.929 F64.8

N26 X.0676 Y1.9141

N27 X1.374 Y.926

N28 Y-1.865

N29 X-1.365

N30 Y-.4555

N31 G03 X-1.3723 Y-.4378 I-.025 J0

N32 G40 G01 Y-.3078

N33 G00 Z.1

N34 Z1. M09

N35 G91 G28 Z0

N36 G28 X0 Y0

N37 M30