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Dual 1215-S Idler Wheel contact

A

alh

New Member
This is a follow up from a previous thread. Turntable was working well, having been professionally cleaned, adjusted, lubricated etc. a few years ago. After some time of non-use, it did not work - the problem was that the idler wheel came very close to the motor spindle but did not contact it. The idler/pivot assembly was removed, taken apart, cleaned, and relubricated (nothing was dirty except the nylon washer that holds the wheel on). I did some careful "dressing" of the wheel but did not want to overdo that. With the turntable off, the idler wheel spins very freely; a bit less so with the nylon washer installed.

With the platter off, the idler wheel still does not contact the spindle, but it is so close that if I tilt the turntable up from the left side, it does and spins properly. With the platter on, the platter very slowly starts and then builds up some speed (have not tried to play a record, but I figure the slow start-up is not great for the rubber on the wheel). The part of the underneath of the platter that the idler wheel contacts is clean. There is nothing loose or funky about the motor spindle.

So - this is a matter of a very close tolerance not being quite right - it is not that the idler wheel cannot contact the spindle, it just doesn't quite (at least when the turntable is flat). Is this a case of needing to replace the idler wheel, or is there something more about the pivot that needs to be dealt with?

Thanks for any advice.
 
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Have you also cleaned the idler, inside platter rim and motor pulley with isopropanol? Just tiny bit of grease or other contaminants on these parts can cause slipping.
 
Next one to check might be the motor and make sure it's lubricated. Was a while since I worked on an idler dual but I think you can disassemble the motor bottom bearing and clean and oil it.
 
I have a dual that doesnt quite make idler/spindle contact but with platter on it runs great. That leads me to believe its not the idler pivot.
 
Yes, the wheel does not make contact with the motor spindle without the platter. My understanding is that when the platter is installed (and the turntable turned on), the inside platter rim pushes to idler wheel a bit toward the motor spindle to make contact with it. That this is not quite sufficient to get the platter rotating up to speed at the start suggests to me that wheel might be just "worn" enough to need to be replaced - and that the slow start would generate flat spots on the wheel.
 
Maybe you could try another go at sanding the idler and a bit more aggressive to make sure you get down to better rubber?
 
A slow start would not itself lead to flat spots. Sustained pressure on one spot might.

I think a motor overhaul is in order.
 
I think slippage between the turning motor spindle and the idler wheel because the wheel is not quite close enough would heat the rubber, which I imagine is not good to do repeatedly. I am curious as to why a motor overhaul would be indicated - the motor spindle instantly turns on at the right speed - no lag there, and it is quite forceful. About "dressing" the wheel - I recall coming across instructions on how to do that correctly (with sandpaper or an emery board) without altering the edge shape but I can no longer find it - would appreciate a link to that if someone has one... thanks.
 
The motor has a lot more load on it when the idler contacts it and it has to move the mass of the platter from a dead stop. But the heat/friction load on that tire is not like a dragstrip racer when the light turns green. :)
 
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