CNC problem : path not corresponding to my drawing.. Is there a problem with my GRBL settings?

Hello everyone,

I’ve got a 1500x1500 x-carve CNC that i assembled myself a year ago. I was usually using it for simple forms cutting and didn’t have any problem with it. I use Easel from inventables for carving.

Here is my problem: I’ve recently aded the new GRBL 1.1 and put inside my old settings from the GRBL 0.9.
Here are the settings :

I really don’t understand why, but the carving path doesn’t match with my drawing or the display on easel !! Ive got some serious shift of 4mm!! Look at the parrallel lines that should be 10mm offset, they are 7mm on a side and 11mm on the other side. Here is the result in image :

(don’t look at the error in the center, only the biggest diamond)
This is my drawing displayed on easel 14
(closed and continus vector !)

For information, the cnc was cutting my parallel diamonds anticlockwise…

Does anyone have an idea of the problem i’m face too? did it already happened to some of you guys??

Thank you for reading my topic and helping me finding the issue !


Steps lost I am sure.

@HaldorLonningdal thank you for your respond ! :raised_hands:
As i don’t hear any step lost from my motors, i guess this is happening somewhere in the gcode? Do you think that changing the $100 and $101 parameters will help ?

Here is another photo off the same problem after trying to fix it… still not aligned :cry:

For information, the first diamond cutting was 2mm stepover for cutting a 10mm mdf sheat. The carving path was followed 5 times perfectly aligned, that’s why i don’t think it comes from a physical step motor « forcing » in the wood. (That already happened to me before, and solved it with calibrating my shield)

Not sure if it is the camera angle or not, but is your router tilted. It does not look perpendicular to the wasteboard. That could cause a problem also

@PhilJohnson Here is the beast when i didn’t have any problem !


Sorry, i don’t speak fluently english… when you mean router, you re talking about the makita milling machine ? If yes, it is perpendicular, just the photo angle deforming :slightly_smiling_face:

1 Like

1 - Hearing steps being lost is difficult unless the motor stall for a brief (or longer) periode of time. step lost = machine have lost synchronisation which can be motor being unable to perform the motion (stall or underpowered) or there is something mechanical that give/isnt tight.

2 - possibly but unlikely in this case

Nice you can work a 4X8 sheet of material thru there. But you really need to get drag chains and dust control on that.
At least shield the Y belts and wheel from debri.