[Hammarlund] SP-600 tuning problems (NEW)

[Joe Connor]

Thanks for all the advice. As you recommended, I cleaned and lubricated the gears, shafts and bushings and the tuning is much smoother. However, I still have bad dial slippage. I think I found the problem but I need your help in solving it.
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>The tuning log scale is attached to a geared collar that should be attached to its shaft by an Allen head screw. Mine is attached with a finishing nail (yes, you read that right, a finishing nail). The nail is driven into the threaded hole where the Allen head screw should be. The result is that the dial scale collar/gear is somewhat loose on its shaft. This, I believe, has caused the dial slippage. 
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>How do I fix it?
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>1. The first possiblity is dropping the panel, removing the tuning-log scale, removing the finishing nail and installing an Allen head screw. The problems are that I don't know the size of the screw and I am assuming that the finishing nail, which is quite tight in the hole, has wrecked the threads in the collar. Does anyone have any thoughts? Does anyone know the size of the Allen head screw? (I see one on a collar in the Frequency Control Unit that might work). 
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>2. The second possiblity is removing the finishing nail, sliding the collar/gear forward slightly, putting some JB Weld on the shaft and sliding the collar/gear back into place. I could even remove the nail, put a drop of JB Weld in the screw hole, and drive the nail back it. Hopefully, the JB Weld would hold the collar in place. I don't like this kind of frig-rig approach but it may be the best choice I have. I'm not sure. 
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>Either way, this is going to be a bear to fix. Even with the front panel off, there's not much room to work. HOwever, this is a nice radio and worth the effort. 
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>                                                Joe Connor