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This one has me puzzled. Someone brought me an Edison Standard Model D to get working. It would play about mid way through a 4 minute record and slow down. Then pick up speed towards the end of the record. I went through it and made sure that the upper works was spinning freely and the motor had ample power. With a good cleaning and adjusting end bearings, half-nut, etc... it played great about a dozen times playing a 4 minute record about three times on a winding. I was called by the owner that the same symptoms have returned. I am stumped. The motor has lots of power. With the belt removed, I can lower the speed adjusting arm and the motor speeds up fast. The upper works spins freely when I spin the mandrel. What am I missing? The tension roller spins freely also. Any suggestions would be appreciated. I will be out of town until next Saturday and won't have good access to the Forum during the week. I look forward to reading any suggestions when I get back. Thanks, Ken Brekke

Sounds rather like an increase of friction somewhere: the carriage rod, the feed screw, or the straight edge...

Also, what horn are they using? If it uses a crane, it might not be adjusted properly...?


-- Bill

All good points. I will have to take a look at it all when it comes back here. I could see if the carriage rod was slightly bent upwards that the friction on the half nut would increase. It puzzles me that it worked great through several 4 minute records.

Ken,

My first thought after the usual lubrication and adjustment would be a spring problem, with coils sticking together. Add some oil to spring?

Marc

Possibly dirt deep in the threads of the feed screw that is being dislodged as it plays. It may be dirty in one spot, or perhaps it has damaged threads along the screw in that spot, so the half nut struggles to get through it and slows down at the problem area, then speeds up once it gets past it. Clean the feed screw with a soft brush and alcohol solution, then examine the threads under magnification. If that doesn't work, you can switch the feed screw with another and see if it solves the problem.