From: trepidation@example.net   
      
   On Tue, 24 Jan 2023 07:36:33 -0800 (PST), Guy Patterson wrote:   
   > On Tuesday, January 17, 2023 at 9:56:42 AM UTC-5, ohg...@gmail.com wrote:   
   >> On Monday, January 16, 2023 at 6:34:48 PM UTC-5, Cursitor Doom wrote:   
   >> > Anyone successfully done this? If so, what's the secret? I've been   
   >> > f***-arsing around for 4 hours today trying to do one on a 1972   
   >> > Grundig portable FM/AM radio and got nowhere. The design is most of   
   >> > the problem. For some reason, the drive pully is completely smooth and   
   >> > affords no grip to the cord whatsoever, so the thing just slips around   
   >> > such that the pointer only moves when it can get a bit of traction.   
   >> > What a f***ing joke.   
   >> Friction, friction, friction... not at the drive pulley where the dial cord   
   grabs but everywhere else.   
   >>   
   >> You must eliminate all possible friction from everywhere in the tuning   
   system. Make sure the tuner's bearings are free of hardened gunk and lubed.   
   When disconnected, the tuner should only require a very light touch to rotate.   
   >>   
   >> See those little pulley's that handle the string? They absorb all the   
   string's efforts if they're dragging (and get worse with string tension on   
   them). If you can remove them, clean and polish the shafts and apply some   
   graphite. If you can't remove    
   them (some are staked on), then run some non aggressive solvent into the shaft   
   and spin by hand until the move with no effort. With a small jeweler's   
   screwdriver, add some graphite to the hub and tap so the graphite gets inside   
   the pulley. Don't "poof"    
   the graphite in as it will probably get on the pulley's surface and transfer   
   it to the string where it might make it back to the drive pulley shaft.   
   >>   
   >> A lot of guys miss the dial indicator.. they're usually just folded metal   
   that slide along the metal dial scale. Those things drag like you won't   
   believe. Sometimes the dial might have a piece of folded fish paper inside as   
   a bearing, but many don't.    
   In any case, clean and polish the edge of the dial with an abrasive if need be   
   to form a highly polished bearing surface. Rub some graphite into the area   
   right where the dial slides along. Careful not to get graphite on the dial   
   itself (unsightly).   
   >>   
   >> Before restringing, get a Q-Tip/ISO and clean the drive pulley shaft and   
   all secondary pulleys of lube or wayward graphite. If you excise all possible   
   friction, you'll find it will tune with no dragging, jerking, or stopping even   
   with less turns    
   around the drive pulley than the diagram calls for (resist the temptation of   
   adding more turns than it calls for - it only causes windup binding).   
   >>   
   >> I've had people pooh-pooh this advice and end up giving me the radio to   
   restring because they don't believe that tiny amount of friction will prevent   
   the dial cord from grabbing.   
   >   
   >   
   > Thank you!!  After reading this, a light bullb went off and I decided   
   > to pull out a troublesome Philco that has always slipped.  I had some   
   > guys at Kutztown restring it about 5 years ago and it worked for a few   
   > days and started slipping again, so I stopped using it.  Nothing more   
   > frustrating than trying to change the station or even tweaking the   
   > tuning as it drifts after an hour of use. They put on some liquid   
   > which was probably rosin and it worked great at the table.  Too bad it   
   > didn't last.  You were right about the pulleys.  With the dial string   
   > removed they spun freely but putting either a little side pressure or   
   > up pressure on them where they might butt up against the peened top   
   > made them stiffen right up.  That is probably why the heavier the   
   > spring I tried the worse it got.  I used the wide end of a flat   
   > toothpick to tap in a bit of graphite moly powder i had kicking around   
   > from Pinewood derby between the pulleys and the shafts, and now the   
   > pulleys spin easily even when I side load them.  I also found the top   
   > rail of the dial binding when I pushed down on it just like you said.   
   > I used a small needle file and dressed the top edge and then sanded it   
   > smooth and rubbed in some graphite with a qtip so I wouldn't get any   
   > on the dial face and now the dial indicator pushes smooth even when I   
   > put pressure on it.  The tuner itself seemed free but I added a couple   
   > of drops of light synthetic oil to the bearings anyway.  My Philco now   
   > tunes like butter and I can even put my thumb on the big tuner pulley   
   > and it still pulls the tuner through. I can now tune and fine tune   
   > this radio for the first time ever. Thanks so much.  I will do this   
   > with every radio I have from now on.   
      
   GREAT followup!!  GOOD onfo!  Very few do that.  Thanks!   
      
   Jonesy   
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