Thorens TD-124/II restoration / upgrade

Would you have any details on that, very curious to know more?

 

Hi Tarzan
Thank you very much.

 

@SLN57 That is a splendidly finished deck. The armboard looks a peach.

 

Thank you Tigerjones. I made the aluminium spacer myself.

 

Simple question, what are the differences between MkI and MkII versions?

 

Some later oils can leach yellow metal. With old Land Rover gearboxes the oil to use was ep90 gl4 spec, so no leaching. I am sure that oils such as straight 30 weights like Morris Golden Film, is fine with yellow metals. I mean, you steep a sintered bush in warm oil overnight, so that it absorbs into the grain of the bush and holds oil. This of course may not be applicable with a little Thorens bush as it is not under extreme pressure.
Were Thorens motors not made by Papst?

 

It's all to do with some EP additives (extreme pressure additives) used in some gear oils. Active sulphur EP additives can react with the copper in the bronze resulting in serious damage. Heat speeds up the reaction in accordance with the Arrhenius principle.

The relevant test is the ASTM D130 copper strip test. In this test, a strip of copper is immersed in the oil to be tested at 40 degrees C and again at 100 degrees C. The strip is removed after each test and checked for staining/tarnishing of the copper. The results range from very little to no staining (1a) all the way to very dark stains (4c). You can look up the copper strip test results on the datasheet of many commercial lubricants.

But just don't use gear oil!

I just looked up the datasheet for Mobil DTE medium, which is often recommended as a good oil for the TD124 has a copper strip test rating of 1b for the 3hrs @ 100 Celsius test.

In my own TD124 I'm currently using a fully synthetic ISO 46 air compressor oil which has a rating of 1a. I've been using the same oil in my TD125 for about 20 years.

 

Interesting Mike. What is viscosity of these oils? Compressor oil usually has much anti- foaming agents in them.

 

The Thorens service manual states that Texaco Regal Oil B is suitable, which is an SAE 20 mineral turbine oil.

The current equivalent is Texaco Regal R&O 46.

"Texaco Regal R&O 32 through 150 are recommended for use in electric motor bearings, air compressors, gears, hydroelectric turbines, steam turbines, combustion turbine generators (gas), marine turbines, and hydraulic systems (except heavy duty systems)."

Texaco Regal R&O contains foam inhibitors and is recommend for use as a compressor oil.

I choose to use an oil with a fully synthetic base stock because it has a lower viscosity index and therefore doesn't change in viscosity as much as it warms up, and I find this helps reduce the speed drift as the turntable warms up.

 

Thanks for the earlier answer Tony.
Does the TD135 have the same motor?

 

Maybe i should sell just the motor from my TD135, it seems to fetch more money than the complete turntable

 

I hate these people who break kit for bits to create a profit on ebay. Shows no respect for the product. What also amazes me is how much they ask for trash. For example

https://www.ebay.co.uk/itm/12553651...d=link&campid=5338728743&toolid=20001&mkevt=1

 

I am not yet ready to break it up, but the time will come soon. It has been in the basement for about 5 years and i made repeated efforts to sell it, but to no avail, in spite of a low price. Brexit has done its part to make it even more difficult to sell a complete turntable, so breaking it up may be an alternative.