Restoring and Improving A Thorens TD-124 MKII

[ashok]

I can't find my tiny antiskating counterweight . Does anyone know how much it weighs ( accurately!).
Thanks.

[missouricatman]

My research suggests that the TD 124 MKII counterweight for the stock tonearm consists of two one gram weights. I have one coming from Germany (hopefully).

[missouricatman]

I contacted Christine at Schopper AG the other day, inquiring about some parts. She got back to me, quite quickly I might add, telling me that they had arranged for a New York firm to provide parts in the USA. In fact, in ensuing e-mails she said that due to the contract Shopper had with the firm, Schopper would no longer be able to directly fulfill order requests from the USA.

The new USA Schopper distributor is Audioarts.co (not .com). The contact's name is Gideon. Gideon also responded to e-mail quickly and will be getting me USA parts pricing this afternoon. The Audioarts.co web site shows they are offering a pretty wide range of audio equipment, but I did not see any pricing there.

Below is his contact e-mail.

gideon@audioarts.co

[kevinkr]

Doing a minor overhaul for a friend on a very early TD-124, this one certainly dates from around 1957, serial number well below 2000..

The bearing and spindle are quite different from later units as you will see in the pictures.

I've rebuilt the main bearing which had swollen, disintegrating nylon bushings and a bakelite thrust plate that it appears someone made from hand.

The end cap appears to be original but is not like the later coined end cap so many people including myself thought was bent. (I've seen enough to now know better)

I believe this bearing originally would not have had a separate thrust plate but having fitted sintered bronze bushings I decided to install a new nylatron thrust plate as well.

The bushings were oil impregnated in hot 20wt oil prior to installation. Despite my efforts to keep everything clean there is lint and other debris from the overhaul so I will flush the bearing with oil prior to installation.

Next I will tear down and lub the motor, this one is on a tight budget so bearings will be retained as will the felts. This motor actually runs ok.

The top platter unfortunately is awol.. This machine will be used exclusively to play 78s.

[brianco]

Originally Posted by kevinkr

...............................................

The top platter unfortunately is awol.. This machine will be used exclusively to play 78s.

20 years ago several of us who used 124 TTs in the UK ran them without the top plate. It was our experience that - with a suitable mat - they sounded better without that top platter plate. (It's main purpose was for DJ use, not sonic quality). I used a French (Spectre?) mat made of a very soft rubber with a thin 'tacky' skin which gripped the disc. Also used a substantial brass/bronze record puck/clamp. The difference between this set-up and factory set-up was a substantial improvement in overall sound quality, especially with regard to giving more space around individual instruments. However a solid, fine grain, graphite (NOT graphite compound.) mat of about 1/4" - 1/2" thickness will make the TT a totally different beast with improvements in all areas. ART (the old Italian company, not the UK company) used to sell such a mat.

[missouricatman]

Originally Posted by kevinkr

The bushings were oil impregnated in hot 20wt oil prior to installation. Despite my efforts to keep everything clean there is lint and other debris from the overhaul so I will flush the bearing with oil prior to installation.

Next I will tear down and lub the motor, this one is on a tight budget so bearings will be retained as will the felts. This motor actually runs ok.

After running a full LP on my project TD 124 and being pretty impressed with the sound, it's time to do the full drive rebuild, so after reading through many of your postings, I've got a few questions for you.

What specifically are the oils you settled on for the main bearing well and the motor bushings?

I got the impression that at least for a time you were having trouble getting a rebuilt motor to settle down. Some days it worked well, other days notsomuch. If I'm correct on that, did you ever determine the cause?

With respect to the drive belt, I gather you purchased a replacement. Several postings suggest all replacements, regardless of source are too tight initially and I get the impression the solution has been to stretch them a bit. Where did you finally source your belt from and what's your take on the "too tight" theory? If you did stretch it, how did you accomplish that and how much did you stretch it?

[kevinkr]

Hi missouricatman,
I use Three-In-One 20wt electric motor oil - not to be confused with regular Three-In-One, you can identify this as the bottle has a picture of an electric motor on the front. I've posted pictures of the specific type I use. I use this in the main bearing, motor bearings, intermediate pulley and idler pulley bearings as well.

My motor problem was quickly resolved - it turns out that I did not sufficiently impregnate the bearings and was too sparing with the oil when wetting the felts.

I've had no further problems in over a year of nearly daily operation.

Soaking the new motor bearings in hot 20wt oil and allowing them to fully cool is important, but it is equally important to soak the felt so that it is not attempting to draw the oil out of the bearing and is wet enough to supply lubrication to the bearings.

I've found the Schopper to be the best belt overall, with some run in it is extremely quiet, and unlike the Thakker belt leaves no residue on the pulley surfaces. The belts sold on eBay by a fellow in FLA (Hollywood IIRC) have turned out to quite decent as well, but not as quiet as the Schopper with substantial running time. The belts seem to stretch a little with use - I have two original belts in good condition and the Schopper will stretch to the same length as the originals in relatively short order. The Thakker stretch a lot as well and ran quietly until the goo built up on the pulleys - this became a major problem in short order with this belt. None of the modern belts except possibly the Schopper run as quietly as a good original.

[kevinkr]

Originally Posted by brianco

<snip>
However a solid, fine grain, graphite (NOT graphite compound.) mat of about 1/4" - 1/2" thickness will make the TT a totally different beast with improvements in all areas. ART (the old Italian company, not the UK company) used to sell such a mat.

Boston Audio sells a graphite mat that is reputedly pretty good. The older of my two tables is also missing the top platter, this unit has the zamac platter (zingy/ringy) that was originally on my TD124/II, and on top of that is a glass platter - I usually play records directly on the glass. Sounds quite good. I also have a Herbies Audio mat that I sometimes place on the glass, but I think I prefer it without. The glass platter which runs directly atop the main platter without the dots seems to damp out the ring in the zamac.

The TD124/II has the upper platter with geltec dots on an oem cast iron platter. The upper platter has a Merrill-Scillia mat on it which is a combination of lead, rubber and cork - it provides quite a lot of damping, and works well with my various SPUs (Meister Silver GM and Classic GM E II) which are quite lively on their own, and relatively unforgiving about things getting through from the drive train and reflected energy during playback. Imaging, depth, dynamics and overall resolution are the best I have had so far.

[missouricatman]

Originally Posted by kevinkr

Hi missouricatman,
I use Three-In-One 20wt electric motor oil - not to be confused with regular Three-In-One, you can identify this as the bottle has a picture of an electric motor on the front. I've posted pictures of the specific type I use. I use this in the main bearing, motor bearings, intermediate pulley and idler pulley bearings as well.

My motor problem was quickly resolved - it turns out that I did not sufficiently impregnate the bearings and was too sparing with the oil when wetting the felts.

I've had no further problems in over a year of nearly daily operation.

Soaking the new motor bearings in hot 20wt oil and allowing them to fully cool is important, but it is equally important to soak the felt so that it is not attempting to draw the oil out of the bearing and is wet enough to supply lubrication to the bearings.

I've found the Schopper to be the best belt overall, with some run in it is extremely quiet, and unlike the Thakker belt leaves no residue on the pulley surfaces. The belts sold on eBay by a fellow in FLA (Hollywood IIRC) have turned out to quite decent as well, but not as quiet as the Schopper with substantial running time.

Thanks kevinkr. Ok, I know the oil you're talking about. It isn't used in cruise missiles (inside joke, but given you've been dealing with suppliers for awhile, you probably get it), but it's a good all-around electric motor oil.

Did you source the motor bearings from Schopper too? And as you didn't mention anything regarding the Schopper belt being too tight initially, I gather that wasn't your experience? Thanks for all the info.

[kevinkr]

Hi missouricatman,
The bearing kit was purchased from jec965 on eBay, I've also used ones from analog depot when they were still available. As long as you make sure to impregnate them properly there should be no problem.

Yeah, I stopped obsessing over the belt tension issue as they loosen up pretty quickly in use, they will stretch something like a half inch or more with use.

I can imagine this is a much bigger issue for Europeans running these tables with the larger diameter 50Hz pulley than it is for those of us in the 60Hz world.

I have never been able to conclusively determine that there were different belts for 50Hz and 60hz installations, as has been alleged, but there are definitely two different belt part numbers over time, but I have never seen the earlier PN. Original Thorens belts from the 1960s are both more pliant and somewhat thinner than any modern belt I have encountered. (More IMHO than would be accounted for by stretch) See my measurements further back in the thread if you are curious.