How do you keep strings of plastic from wrapping around the blank during turning? I'm constantly having to stop to remove waste collecting on the blank I'm trying to cut. Holding a shop vac nozzle nearby helps somewhat, and removing waste with a toothbrush does too, but both require me to...
Best thing I've found for polypropylene? (chopping board material) is a very sharp hss tool. Fairly low cutting speeds too or risk snarling up in the continuous swarf.
Delrin will chip very well with carbide if you cut heavy, so long as you can keep hold of it well enough.
One thing I have learned with plastic is clean your lathe before and after, because if you mix it with metal swarf you can cut yourself cleaning up and if you turn steel after plastic without cleaning up first the steel swarf melts the plastic swarf causing stinky smoke.