I have a newly restored model 70 cathedral I've been working on for some time. Not in any rush just a hobby. Anyway, it plays nicely but when I turn the tuning knob it sometimes slips. I was looking at the mechanism which is a spring loaded "clutch". The hole in the very front were the the tuning shaft exits seems to be oval, vertically. When I push down on the shaft it no longer slips. Is it worn oval or is that how it was manufactured? If it's worn, can it be repaired and how? Maybe someone can shed some light on this for me. Thanks.
Picture please if you can.
I think this is a common problem with 70s and 90s. You might be able to ream the hole out and install a bronze bushing from Lowe's or Home Depot. Might have to use a little JB Weld to hold it in place.
Steve
Thanks for the info. and a possible solution.
I've never seen one of those worn that much, at least not on any of the sets I have with a similar mechanism, but someone had the good sense to grease most of those periodically. I agree, reaming out the hole and installing a press fit bushing would likely solve the problem, it would take some precision to ream the old hole out in just the right place. However since it still sort of works you could just live with it unless you plan on making this 70 a daily driver.
Regards
Arran
After thinking about it, I just may leave it alone. Although Steve had a good idea with his fix. It's not like I'm going to use this radio everyday. I have the capability of reaming it straight but would still have to drill out the steel rivets holding the whole assembly, dis-assemble the spring loaded part to be able to remove the shaft to do the reaming. Maybe, we'll see. I have a few other radios I'm itching to get at like an RCA 128 I've had for two years and it's staring at me asking, "am I next".
Thought as much. An aggressive spring might keep shaft where it needs to be in the groove.
I have a thought that may be a bit unconventional and crude but since it won't be seen once the chassis is installed in the case I might give it a try. Also, it won't alter the original mechanics greatly. I'll try it first to see it I'm crazy or it might just work. I'll let everyone know after the experiment !
As promised, here's my fix. I wired the shaft in a downward position to the point where the shaft was at the bottom of the oval hole. This is the position it was at when new. I then looped a piece of plastic around the shaft. Plastic like from a sandwich bag. I then put a little "blob" of steel stick, a puddy type epoxy with a metal filing filler above the shaft and let cure. I then pulled the plastic out from under the puddy. The plastic was to prevent the puddy from sticking to the shaft. It worked perfectly, but I still have my "ruthers". Since this is not a everyday user as are most restored radios, I might just take it off. What do you guys think?
Here's a pix of my labors. Also, If you look closely, you can see the upper right corner of the escutcheon is broken off. I bought the radio like that. Any have one they want to sell? Plastic or metal, either is ok.