Hi, No, its actually trying to create these lines. Nothing wrong with z. I re-ran one of the scrapped parts. There is certainly a machined line between the points.
I deleted the whole file and created it again and i'm running fine again. I really have no idea what was causing that.
Also, if the Z was having problems it would not be correct at all other points, its engraving hundreds of letters and attempting to join one in 10 or so.
Bizzare, I doubt I will ever know what caused that. It must have been in the code so can't be down to Mach but how in the hell it got there I do not know.
Cheers
Al.