New 45XP - Trouble with Edge Start Transfer

[andrewwong2000]

Hi,

First of all I'm new to using a machine plasma cutter.

I've set up a new 45XP, and am having some trouble getting Arc Transfer on Edge Start.

I'm using some old 5mm black steel flat bar with handbook HT 5mm Mild Steel settings. I've hand sanded the edge of it to remove the oxide layer/rust
For a number of starts, the pilot arc runs but there is no transfer (right on the edge).

I've also sanded the point where I put the 45XP earth clamp on the work .. tested with a meter 0.1ohm.

To test a theory that the arc can't start I put a thin sheet of alum. over the top and the transfer worked fine.
Plasma pierced the Al sheet, cut a number of slots just fine without changing anything.

Does this prove that its something to do with conductivity ?

I'm asking:
i. For machine cutting does the metal have to be really (bright) clean to edge start properly - eg. I need to brush my steel clean before I machine plasma cut it ( I don't need to do this with the hand torch)

ii. I've removed lead-in from my Toolpath hoping that that proves the lead-in distance was the key issue but whether it is 0-3mm it didn't matter

Appreciate any advice for a newbie.

Thanks,
Andrew

[acourtjester]

For edge starting I position the tip at the half on and half off edge, and do not use a pierce height but a cut height with a small pierce delay time

[andrewwong2000]

Thanks Jester!

Will try that out and see how I go

[djreiswig]

For edge starting I position the tip at the half on and half off edge, and do not use a pierce height but a cut height with a small pierce delay time

This is how I do it. I use a mirror to see where the nozzle hole is and place the hole halfway on the material.