NEED HELP w/ 4th Horizontal axis using Grbl!?

[andrewjohnbeaton]

Hello everyone!

I need help configuring grbl and fusion to run as a Horizontal mill with a reversed z axis. 

I have been looking forever and have to get this project done asap! 

1. Do I need a special post processor?
2. Which toolpaths  and settings would be able to make me something that looks like a motorcycle tire? 

I need help walking through step by step.

Attached is a video of the set up.

THANK YOU SO MUCH for your help!

[PG.Eng2]

Hereby 2 remarks which might or might not help:

- grbl standard version on 8-bit AVR only supports 3 independent axis, no 4th / rotary axis.

- If you only flipped the z-axis on the machine you don't have a right hand cartesian coordinate system anymore.