Removing pinned gears/hubs from shaft

dkoczur

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I am restoring an antique radio that has a motor driven selector. The selector mates with the variable tuning capacitor. The radio can be tuned remotely via the motor /cam assembly or manually like any other radio. The motor will drive the cams and tune the radio, however the selector mechanism is so tight the manual tuning will not operate the selector with the selector cam assembly attached. I have tries penetrating oil and lubricating the shaft of the selector mechanism with no improvement. The shaft has a gear pinned on one end and a hub pinned on the other end. I am told the pins are tapered, but I can't tell which is the smaller end to attempt to drive them out. I considered attempting to drill out, but clearances are too small for anything but a very long drill, and I'm not sure how to make sure I am drilling on the pin. The shaft is 3/8" brass, the pins appear to be steel. No one on various radio forums that I have contacted has come up with a solution. I was hopping aI might find some one on this forum who could help. If pictures coulee help, I could post some of them. Thanks for any suggestions.
 
If it's what I think it is, with the shaft a fuzz under 1/4", you're facing a long and difficult time. The few pieces I disassembled that were similar was to salvage the gears. Small pitch, large diameter. What I did on the stuff I wes working on was to make a suitable pin punch; small... ...

I tried one way and if it didn't work tried the other. Because the shafts were so old and di-simalar metals, sometimes had to swap back and forth a few times 'til I got it to move. In a few cases, I had things lined up right, In a few, I never did get the pin to to move. On again/off again, as it were.

The punch was surplus welding wire(?), hard enough to work but not real hard. About 0.040" / 1mm diameter let into a larger piece to keep things straight. Key stock, I think. The hammer was small and light(X-acto), and my strokes were light. Most worked... eventually. A few didn't. Those gears already have shafts if I ever need them.

I won't say it'll work for you. But it did for me. Most of the time... ... Good luck with it.
 
Do you have machine tools? If this was me, I would make a simple press, with a frame to go around the shaft and a threaded screw with the tip turned down to just smaller than the pin diameter. Sort of like a typical gear puller but with a much smaller spread, just enough to contain the shaft and allow the pin to pass. It would allow you to use controlled pressure without damaging anything. Pounding on a drift might bend the brass shaft.
 
My experience with taper pins (considerable) is to measure the projecting ends of the pin, establishing which is the small end, then don't ***** foot around, give the small end a good whack and it should come out; tappy-tappy- tapping on it will only peen it over, making it all the harder to remove, then it must be drilled out, and likely having to be reamed out to a larger size to make things line up again.
 
Do you have machine tools? If this was me, I would make a simple press, with a frame to go around the shaft and a threaded screw with the tip turned down to just smaller than the pin diameter. Sort of like a typical gear puller but with a much smaller spread, just enough to contain the shaft and allow the pin to pass. It would allow you to use controlled pressure without damaging anything. Pounding on a drift might bend the brass shaft.
Make from steel by drilling hole in stock same size as diameter of part with pin.

Now cut to side a slot size of SHAFT so hole is c shape.

File slots drill through hole for pin and pressing screw.

Use Allen socket screw for press as they are very hard.

File slots if pin is higher than surface.

Brass also expands well so a Weller 250 watt iron with a custom tip made from length of number 12 solid wire wrapped around the shaft will heat it up local so one could possible gently use pliers or small punch

Sent from my SAMSUNG-SM-G930A using Tapatalk
 
Have attached several pictures to show th e hub pin and the gear pin. Without removing pins, the end plates will not come off. I have also included one picture of the whole assembly.

PICT0057.jpg

PICT0058.jpg

PICT0059.jpg

PICT0060.jpg

PICT0061.jpg
 
My Dad used to do lots of radio work. He had an automatic center punch, that he ground the tip flat, and to a small straight diameter (think like a straight shaft / pin sticking out the tip). A couple of punches from either side would get the small pins moving.
 
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