Z-axis coördinates problem after running program

Hello,

I just got my CNC set-up with LinuxCNC and I 'm running into a problem. I'm also pretty new to CNC in general.
I'm using Fusion 360 for the CAM and the standard LinuxCNC post processor in Fusion.

After I run a program something with (I think) the coördinate system is messed up, because I can't run my second program.
The error:
'Linear move on line 10 would exceed joint 4's positive limit'
Joint 4 is my Z-axis (it's a dubble gantry machine with 5 stepper motors)

 

This is what I do:
- Home the machine
- Jog to the work pieces zero point
- G92 X0 Y0 Z0
- Run the program

What I notice is when I start LinuxCNC I see G53 coördinates on the screen. When the program ends, I see G54 coördinates on the screen.

 
 

Is it possible that there is a very long tool offset in the tool table?

Thanks for the quick reply Andy!

Do you mean in Fusion? If yes I added a screenshot.
Should the lenght and diamater offset set to 0?

 

No, the LinuxCNC tool table.

What is line 10 ?

I don't know... how do I access the tool table?

this is line 10:
N20 G53 G0 Z0.

I don't have a tool table I suppose. When I want to open it (under file > ).. it does nothing.

In the bottom of the screen (Axis) it says: Tool 3, offset 1.273, diameter 0.201

Why does numbers? It's a 1 flute 3,175mm (1/ end mill 

It looks like Fusion is making an invalid assumption about your machine.

What is the top of Z travel in machine coordinates?

Fusion assumes that G53 Z0 takes you to the top of Z travel. You might have a Z max of -0.1 and home at zero, for example.

I think you are right.
The Z-axis limits are 0 to -60
How can I fix this?

Which version of LinuxCNC are you using? I think that we fixed this...

github.com/LinuxCNC/linuxcnc/pull/1047

Hey Andy,

I’m running the latest (stable) version:
LinuxCNC 2.8.2 Debian 10 Buster PREEMPT-RT ISO

That's a bit of a worry, as the fix went in between 2.8.1 and 2.8.2.

To solve your specific problem right now, try setting your Z axis max limit in the INI to 0.00001