Stromberg Carlson TV-125 (DuMont RA-103)
 

Hello Group;

I have a Stromberg Carlson TV-125 console. It has a good CRT and looks to be very restorable which I plan to do.

It has a broken InducTuner shaft. The way the shaft is broken I do not think I can make a reliable repair using epoxy although I may attempt it.

If anyone has a spare shaft from a junk set please let me know. I would be very interested to purchase it.

It looks like there are two good flat spots on either side of a clean break so glue/epoxy may make a solid joint. The hard part is avoiding getting glue on the contact ring around the shaft.

if the break is right up to the coil, be careful using JB weld or filled epoxy, its aluminum filled, i think, might be conductive. maybe there is a fiiled epoxy, (for strength) that isnt conductive.

I know that JB Weld is mildly magnetic, at least it was several years ago when I used it near a strong magnet. It would 'creep'.

if its magnetic or conductive you wouldn't want it too close to the coils. From a mechanical standpoint it works great.

I think the only way I would attempt to mend that break is to use a table top or small lathe, gently chuck each end of the inductor shaft, align them as perfectly as I can with the broken ends mating exactly as they should and then trying non-conductive epoxy. I really don't think a successful mend can be done on these pieces considering how close the break is to the ring.

The key to any good adhesive bond is to have the surfaces immaculately clean, which is easier said than done when you're dealing with an oil soaked mechanism. Ceramic is a porous enough material that it can wick up oil over extended periods of time, in which case you may have what seems like a good initial bond, but it could potentially fail at some point in the future. Over on Toms thread I mentioned milled fiberglass and epoxy as a substitute for JB Weld.

Has anyone ever investigated using replacement shaft material? McMaster-Carr stocks ceramic rods and many flavors of plastic rod stock:

http://www.mcmaster.com/#raw-materials/=10vpk6o

There are probably other suppliers. McMaster is just one that I'm familiar with.

I guess the shaft width is the critical factor. Perhaps someone with a caliper could measure it.

If nobody sells rod stock of the right diameter, it seems you could put a larger rod in a lathe and mill it down to the right diameter. Ceramic isn't very machine-able, but the right kind of plastic should be.

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html