CNC Plasma Table Using Cut50 Cheapo plasma cutter

[MeJasonT]

Still related to HF noise as you have to overcome triggering the machine on whilst maintaining directional control without the noise created by the Plasma/machine generated noise affecting your control.

Triggering the Plasma cutter was a real pain in the butt, every time i triggered the torch the controller would hang up (GRBL/Arduino UNO Pcb). The HF noise just saturated any circuitry i tried using to switch the pilot ark and trigger on.
Whilst sitting in the one room in the house where im alone and can have deep thoughts without interruption - the toilet.
Hey guys you should try it, it only fails if you have a partner who comes in and talks to you - Its bliss the only place in the world i'm free to think.

So the idea, optical fibre. light is unaffected by noise,et voila.
There is plastic fibre out there which is cheap and can by driven using simple electronics

Attachment 12542

and the fibre
High performance plastic Fiber optic cord SH4001 | eBay

complicated isn't it

I used two single ended fibre links ie they are simply switching circuits not 2 way communication links.
one for the trigger and the other for the Pilot Ark.

The cheap Chinese plasma cutters are scratch start like an ark welder, this is obviously difficult to do with a CNC table, it would require the tip to be moved using a Z axis command to strike an ark then move back up to clear the work for the cut.
timing would be critical, when would you move off to make the cut. This is now getting into the realm of a torch height controllers, a topic for another day.

This guys post on machsupport.com explains how converting a HF plasma cutter into a Pilot Ark machine
https://www.machsupport.com/forum/in...?topic=20076.0

I use a motor cycle starter relay to make the contact, there are Gcode commands i use to switch on the Pilot Ark long enough to strike an Ark the it is disabled saving consumables. There is no harm in leaving it on but your tips will only last an hour for a few cuts. The trigger on the gun has been removed and my second relay operated by another Gcode command controls the triggering of the plasma cutter

motor cycle relay like this one
12V Starter Solenoid Solonoid Relay Quad ATV Motorcycle BRAND NEW | eBay

I'm using the Spindle enable and suds pump commands for my triggering and pilot ark control.

Here is some of my inspiration

IRNAS :: Good-enough useful-open-hardware CNC/Plasma cutter - Plasma cutter selection

IRNAS :: ToslinkCNC - Optical communication for CNC control - design overview