advertisement


Thorens TD-124/II restoration / upgrade

I may swap back to the original bushings as well... they've been sitting in solvent for about 9 months after rebuild, but the AS bushings are tight. I don't think this is necessarily an issue with my setup but I do wonder about mucking up the motor shaft long term.

That was the conclusion I came to. I’m sure the AS bushings are fine, especially when vacuum-loaded with a good lubricant as mine were, but I just feel more confident running the original bushings as they are long-term tried and tested and mine seemed to be in very good condition.

I’d be very carful to ensure any oil you try is safe on sintered bronze. Many modern motor oils are not. I’d question the manufacturer if necessary.
 
Would you have any details on that, very curious to know more?

There is an old thread here which has more than I can remember. It is one of those things where I learned enough to confuse myself but not enough to really understand the topic. Really I just wanted to be told ‘buy this stuff, it is the same as Thorens used’, but until I found the stuff I linked to I was never confident I had!
 
Simple question, what are the differences between MkI and MkII versions?

Short answer:

Cosmetic: chassis colour, switch design, and a different mat design.

The motor suspension was also changed (the /II has longer posts to enable two sets of rubber isolation grommets). This can be retrofitted to a MkI today as third-party posts are available. That done there is no advantage to a MkII, the difference is purely a cosmetic face-lift.

Longer answer:

There are actually several revisions of MkI where the chassis and step-pulley underwent changes, plus the E50 motor (which wasn’t made by Thorens) underwent a revision with slightly larger coil windings.

The iron vs. alloy sub-platter is version independent. Both could be ordered with either, though in practice most MkIs seem to have the iron and most MkIIs the alloy.
 
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 higher 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.
 
Last edited:
Were Thorens motors not made by Papst?

I’m pretty sure Papst didn’t make the E50 motor which was fitted to all TD-124s, though I don’t know who did. I’m sure Thorens bought it in though, it isn’t a Thorens product.

Thorens did at some point after 124 production stopped offer a Papst replacement for the then unavailable E50 as a service option if any had been run dry, burned out or whatever. Views are split on it, some feel it an improvement, others a step backwards. They do crop up now and again. There were several being offered NOS for around £300 a throw on eBay a while back, which is a lot less than you’d pay for a NOS or even pro-serviced E50, which is probably a good indicator.
 
Maybe i should sell just the motor from my TD135, it seems to fetch more money than the complete turntable :confused:
 
Sadly that is likely true, but it would be criminal to break up a nice 135, they are really cool little decks. You may find the step pulley is the same too, I don’t know, though I do know the main bearing is totally different (smaller). I’d keep it complete if I had one.
 
I hate these people who break kit for bits to create a profit on ebay.

I’m in two minds as it does enable better examples to be fully restored. Once parts are gone they are gone. I’ve certainly bought quite a few vintage Thorens, Garrard, SME etc parts over the years as I am very obsessive about condition. I’ve also got a lot of TD-124 parts for sale in the classified area somewhere, but nowhere near enough to build another deck!
 
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.
 
Last edited:


advertisement


Back
Top