@Jim R. posted:
1. Plastic also becomes more brittle with age.
2. The zinc problem is with subcontractors in China who O gauge manufacturers depend on for zinc-based components such as couplers, car frames, trucks, truck sideframes and, in the case of my MTH American Freedom Train GS4 from 2002, the locomotive skirting. Some folks here have decided the problem is the alloy. Funny we went decades without any problems until China production became the norm.
So who is to blame? The subcontractors because of ignorance? The Chinese government for not setting industrial standards? The main contractors for not vetting the subcontractors? The import manufacturers for not tolerating top quality control? The U.S. government for allowing domestic manufacturing to be supplanted by foreign manufacturing?
3. Plain and simple, I don’t know. But it’s clear O gauge zinc pest as in Ben’s sample here is the result.
1. Indeed it does; but the OP had issues straight out of the box. I had a K-Line hopper with the same thing. The examples you site are caused by over stressing the material, not a defect in the material itself.
2. At the risk of "beating that dead horse", it's not a Chinese problem, other than the fact that EVERYTHING we buy now is made there. As I've said (every time this comes up) I've had parts made in Italy (Rivarossi), Japan (KTM brass loco drive components) and good ol' USA (John English and Mantua and even on rare occasion, Bowser). Not excusing it, but it happens.
3. I agree completely.
Mark in Oregon
PS: Yeah, for some reason, a plastic bodied O scale steam engine just seems... wrong. 🤔 🙂