never use z-lift.

well ended up with odd setting that caused considerably fewer stringing/ Turning cooling back on to 100% really helped.
Also went with shorter slower retractions.

But in the end it's just not going to be a sensible option with the delta.
The speed alone makes it highly inpractical. I print the pla moulds at 100 mm/s
going down to 40 and 10% first layer puts a small mould set up to about 8 hours.
Plus with ptg, you can't do both halves at once, just too muh stringing between parts.
I think you could get away with printing one part at a time. Might try it at some point.

I'll try again at some point with one of the other printers.
meanwhile I'll stick with pla and just beef up the layers and infill.

Cheers for the help :-)