Originally Posted by
repechage
referencing a bit, and not locating my old plastics textbook, good chance not made of Delrin. Plenty of acetels.
a burn test would answer much as many plastics are easy to identify by the smell, but Delrin was expensive, the self lubrication properties as observed in many Simplex mechanisms for example could be found in cheaper materials.
UV is a killer of many a plastic.
If not "Delrin" i.e. a particular formulation, then almost certainly "delrin" i.e. a similar POM plastic.
I had a quick look, didn't find anything official from the mfr. that stated which plastic, but net references, if the mention a type, universally say "(D/d)elrin".
I have one on a bike, and the subjective impression was that it had even more of a damped, dead feeling that the aluminium versions also seem to have, compared with a all-ball type headset.
Yes, smooth and tight, but road-feel seemed muted.
ob.pic:
And no, I'm not taking a bic lighter to this one to smell it.