4th axis tangent to path XY

Yes.
A axis jogging is working as normally do.

The joint 3 output will return to zero if the joints are not currently moving.
Also, are you sure that you are using the version that has the rotation axis on Joint 3?

INI and HAL file attached. The A axis is TYPE=ANGULAR.

It is jogging as normal with jog buttons but no motion with X-Y movements.

Anyway, I have got some solution from sheetcam that will give C axis command in G code it self.

C-axis rotation in the CAM is a better solution. I wrote tangentkins 10 years ago and have been telling people not to use it ever since...

Anyway, thank you for your support.

Actually I am preparing for a job that require knife engraving with autolevelling.

I need to solve the autolevelling.

I'm in need for a solution like this.
Your component seems like an elegant approach.

I need to either have this operational by calling an M code,
or have this non-operational by having A=0degrees and homed.

The other hypothesis that I have are:

-> custom Mcode calling for a python function which interacts solely with the A axis
-> Having the A output automatically done by the Postprocessor (sheetcam in this case will be the CAM)

The problem with the 1st option is it's complexity in python

The problem with the second option is having the A axis moves be in Sync with the X/Y axis movement during Arcs, because of the varying velocities in these axes. How can i make sure the A move speed will be in sync with the X/Y move speed?

This will be used for automatic beveling on plasma/laser, it's not a blade so there won't be "blade collisions" to the material. i don't ever need to "lift the blade" like typical knifes have to do in curves.