Homemade, cheap, plasma CNC

Man, this is strange... Sorry for the pile of questions but I can't really get my head around what is happening.

When you say 8.4mm do you mean when it is moving between cuts?
What is the Safe Height parameter when it does this?
Does changing the Safe Height parameter change thie 8.4mm to something else?
If you do Z axis MDI of say 20mm does it actually move 20mm?
If you set the Safe Height parameter to a low value like 20mm does it still give the warning?

RNJFAB wrote:

No green ball Tommy.
 

My dog has one ... oh that ball !
Did you zoom in on the 0,0,0 coordinates? It is small, very small.
Also i did check on one of my machines today while i was chasing a gremlin in the electronics, PlasmaC and QtPlasmaC will always have that green ball on all machines with limit switches and proper homing... soooo
Check the G code quick reference for offsets and cancel all of them, there are at least 2, maybe more, then do the "torch just under the slats" exercise again and touch off Z.
I am blindly hoping there is a tool offset active messing things up, otherwise i am out of ideas ... or am i ???
Can you upload a video on youtube with the normal use process, from start to ... when things mess up.

Man, this is strange... Sorry for the pile of questions but I can't really get my head around what is happening.
** that make a few of us Phil. It has me stumped and frustrated **

When you say 8.4mm do you mean when it is moving between cuts? YES
What is the Safe Height parameter when it does this? anything over 5mm
Does changing the Safe Height parameter change thie 8.4mm to something else? NO
If you do Z axis MDI of say 20mm does it actually move 20mm? YES
If you set the Safe Height parameter to a low value like 20mm does it still give the warning? YES, But if i go down to 5mm I don't get the error.

Tommy
Did you zoom in on the 0,0,0 coordinates? It is small, very small. ** YES, no green ball. **
Also i did check on one of my machines today while i was chasing a gremlin in the electronics, PlasmaC and QtPlasmaC will always have that green ball on all machines with limit switches and proper homing... soooo
Check the G code quick reference for offsets and cancel all of them, there are at least 2, maybe more, then do the "torch just under the slats" exercise again and touch off Z.
I am blindly hoping there is a tool offset active messing things up, otherwise i am out of ideas ... or am i ???
Can you upload a video on youtube with the normal use process, from start to ... when things mess up.

** no ide how to find tool offsets in the g-code, sorry. **

Can you check the hal pin plasmac.cut-height and make sure it changes when you change the Cut Height parameter in the GUI.

Oops, that should be plasmac.safe-height

RNJFAB wrote:

** no ide how to find tool offsets in the g-code, sorry. **

You can check in the status page by clicking the STATUS button in the PARAMETERS tab.

Look for:
g92_offset
tool_offset