[ODPILOT]

        7/26/13 Hi all. I'm restoring a 53-1750 radio/phonograph console.
The phonograph speed selector dial/knob just spins on the shaft.
The shaft is a semicircle shape while the hole in the bottom of the knob is circular. Am I missing some part or some insert that might go on the shaft or perhaps inside the knob that allows the knob to grab the shaft?? Doesn't seem like anything is broken. Thanks,
Mike

[Mondial]

It looks like you might be missing the spring steel insert which fits in the slots across the hole in the knob. This is a thin leaf spring which puts pressure on the flat of the shaft and prevents the knob from turning on the shaft.

It might have come loose when you removed the knob. If its lost, you probably can fabricate a workable replacement from thin sheet metal.

[BrendaAnnD]

I'm afraid it's worse than that. That's a split shaft, and one half of it is gone. Replacing the spring clip in the knob may help temporarily, but the other half of that shaft will break off before long because of the added torque against it because it's other half is gone. Look into having a new shaft fabricated. It shouldn't be too difficult, as long as you can get the old one out. I've even done a couple of these myself.

[ODPILOT]

I wondered if the shaft was split, or just missing the insert - and unfortunately, looks like you're both right. Crapola !! I'm gonna have to have new shaft made and then make some kind of metal insert to go on the new shaft - so it can lock into the knob. Thanks people, I appreciate the help.
Cheers,
Mike

[ODPILOT]

I just used a strong magnifier to examine the (alleged) broken shaft -- and realize it is not cracked or broken. Looks like it was designed with a D shape (or semicircle) design in order for a retainer to be able to hold on to the flat side of it. I've since looked at someone elses 53-1750 and it has the same D shaped shaft. I believe it is just missing the metal clip/retainer -- which are not available -- so I'm gonna get a thin piece of steel and see if I can bend one into the shape it needs to be for this to work. Thanks
Mike