[Arran]

I can't figure out why Majestic used pot metal for the tuning plates in this set. It's not a low-cost set and I have lower quality and lower cost sets from that same year that use copper plates. Even Philco used better plates. Seems someone was trying to squeeze out a little more profit at Majestic.

The pot metal isn't in the tuning plates themselves it's in the hub that mounts the plates to the tuning condenser shaft. To my knowledge no manufacturer attempted to make condenser plates out of pot metal even back in the 20s.
Regards
Arran