TD-124 Idler Wheel Carriage Assembly Problem

Macquid

Member
2012-09-27 1:10 am
In the 16rpm play position (as well as when switching into that position), the upper set-screw on the far end of the articulated idler wheel carriage assembly of my TD-124 rubs against the chassis to such an extent that the idler wheel won't swing over sufficiently to make contact with the step pulley (please see photo).

Meanwhile when the platter is removed the idler wheel can easily be pushed manually against the step pulley... during which I can feel and hear that the set-screw is lightly rubbing against the chassis.

Although the set-screw also sits very close to (or against) the chassis at the other speeds, the idler wheel does at least make sufficient contact with the step pulley to play at speed... though only barely just at speed for 33rpm (which is the only one I can easily measure since it's a non-magnetic platter).

Any suggestions about how/where I can adjust the carriage assembly so that this set-screw sits a little further from the chassis in play position? Or how else do I fix this issue?

Thank you.
 

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  • TD-124 Idler Wheel Shaft Set-Screw.jpg
    TD-124 Idler Wheel Shaft Set-Screw.jpg
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Hello Macquid

I looked at my TD-124 which happens to be in a state of disassembly and found that the set screw you mentioned clears the chassis by about 1/8" in all speed settings. The only way that the set screw could be interfering with the chassis, is if the idler wheel were too small in diameter. The diameter of my idler wheel is 3.118". You might want to check yours.

What is the history of your TD-124? Could a previous owner have messed with it?

That's all I can contribute at this time.

Sincerely

Ralf
 
Last edited:
Hello again

Something else just ocurred to me: With the platter removed, the idler wheel is not constrained by the inside diameter of the platter and it can move outwardly until the set screw interferes with the chassis. So, when checking for interference, position the idler wheel at 6.383" center to center, measured from the center of the platter bearing. That is where it would be if the platter were in place.

Sincerely,

Ralf
 

Macquid

Member
2012-09-27 1:10 am
Thank you very much Ralf. Thanks to your observation I finally understand why the carriage-end was positioned at the extreme left when the platter was removed... as shown in my photo.

Regarding the lack of contact at 16rpm with the platter in place another helpful person in still another forum wrote:

"I had a similar problem although it was years ago now and time fades my memory. It turned out to be the linkage needed a good cleaning and relube -- there are some 'folding,' for lack of a better word, sections that were not properly moving under the gentle pressure applied by the assembly.

I found this out by pushing with my finger on the offending screw and noticing that it would indeed move to where it should be given sufficient energy. Maybe your issue is as simple as mine was."

Although I had cleaned the linkage, etc. and lubricated notably all the points mentioned in the service manual and in different websites before I made my original post here, after reading the above remarks I also put a tiny drop of oil on a couple of other points in the linkage system where there might be friction "just to see".

That did the trick and the turntable now also turns correctly when in the 16rpm speed position.

Thank you again!

Friendly regards,
Alan
 

kevinkr

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