Low budget plasma setup, what do I need?

tecno wrote:

Hi Rod,
I am redesigning the Z and yes I will provide with floating head.

The torch is a P80 type with power hose and a wire for HF so I assume it is not shielded?

Nope, pretty sure it is not shielded.
Although a shield can be made for any torch and attached to the cup.

That will do just fine.
Using one of the carriages for the floating part is quite easy to implement, but my drawing skills are gone the way of the Dodo, but still i will give it a try later, like at 2 or 3 AM when i move to my bedroom to catch some zzzzz.

Nice and really nice !

20mm is plenty. it just have to move so it can trigger a micro switch/proximity sensor, so even 5mm will do in a pinch.

I think you only need enough movement to allow a safe overrun, my Z axis has a maximum feed rate of 60mm/S (3600mm/min) and accelleration of 600mm/S/S which should give an overrun of around 3mm but my float movement is only 1.75mm so I just make sure my probe height is good and my probe speed is not too fast.

Oops, another Phill mistake...
I have 4mm of float movement and the switch activates at 1.75mm so I have 2.25mm for overrun. I could probably up my accelleration and make it stop within the 2.25 but... if it aint broke...