[Oldie Goldie]

I had no idea the heart of the tuning mechanism was based on such an unnecessarily complicated fragile design. With such crucial close tolerances where any wear or slop the thing literally springs apart!!!
Bad BAD design. I would have incorporated a second spring clip to hold the inner shaft in after it's snapped in with the ball bearings.

I suppose I could put the two inner ball bearings and the spring in a plastic baggie. Put the stupid thing back together, put a dab of water based glue on the inner tuning knob so it stays in for cosmetic purposes; than just settle for having just the course tuning control.
Philco.....I should have bought a Zenith or a good solid General Electric.