[RONWELL]

I'm designing a compact plasma table. watching videos of other DIY tables, I noticed they all have a Z axis and appear to move the Z axis before the start of each cut. I have 30 years CNC operation and repair experience.my thought is manual adjust the torch height, just like I do on oxy torch burning tables. With the templets that I use my plasma torch is 1/16 to 3/32" away from the steel. what is the PRO's & CON's thanks

[KH0UJ]

On a plasma machine the tip of the plasma torch needs to touch first the material (plasma torch OFF) then retract to a configured value in mm, touch material > limit switch triggered then retract 2mm> start the plasma torch/air then cut moving XY, on an oxy/acy mode the torch needs to preheat the material (configured in seconds) then trigger the extra oxygen valve to begin cutting. same CNC machine different torches

[digger doug]

Yup...what he ^ said.

Also, during the cutting, the plasma torch z axis is constantly moving to keep the torch height constant,
usually based off the volts between the torch and ground.
The plasma flame is cone shaped, so any height changes, results in a width change, and hence a bad part.

Oxy torch is much more tolerant of height.