Thorens TD 124 Rebuild Questions

[bob06]

Also I noticed a difference between my TT and some pictures that I've seen. My motor mounts are close to the cast aluminum frame. First is a picture of my TT motor mounts. The mounting shafts extend above the frame surface and there are grooves for the retaining clip to fit either where they are now (low and close to the frame), or higher up on the shaft. (Here you can also see the very dirty drive pulley which I will clean up on the rebuild)

View attachment 1415724

I also have seen several pictures like this one, where the retaining clips are at the higher of the two grooves, further away from the frame, and with additional rubber (I assume) absorption on the motor mount shaft...

View attachment 1415730

Can you all educate me on these differences? Should I aim for picture #2, with additional parts / absorption in mind?

Your second picture is of doubling up on the motor mounts. (Not a bad thing) If your doing a rebuild changing the motor mounts to new are a must.

 

[heyraz]

It's a "hung motor design". Make sure nothing but the 3 rods touch the grommets. If there's contact to the frame, you'll hear motor vibration.
I think to use the springs...the stock rods have to be replaced with longer rods. One of the longer replacement rods takes more effort than the others.

 

[TD John]

Thank you, still learning.

I have read through a lot of the rebuild material on theanalogdept website. Do you think that it's safe to assume I will have to break apart the motor and clean given 1958 manufacture and non-use for 30+ years?

What is the group's preferred source for new bushings, oil, other parts?

 

[TD John]

Bhamham, there are a couple of sources from Moldova that I see on eBay for built up plinths. Do you recall who you got yours from?

I've got three TD-124s, two type 1s and a type 2. My favorite plinth is a rounded Ortofon classic like Heyraz' that a guy in Moldova made in piano gloss black.

I've got three TD-124s, two type 1s and a type 2. My favorite plinth is a rounded Ortofon classic like Heyraz' that a guy in Moldova made in piano gloss black. It's laminated plywood constructed, weighs around 30 lbs and cost $290 shipped to the US. He even made a matching armboard for my 12" tonearm. The paint was so thick on the armboard I had to re-drill the hole for the tonearm and the mounting holes but overall very pleased with it.

Agree with MRL_Audio, a Denon DL-103 would be a good match for your tonearm but you'd need a step-up transformer or MC head amp if you don't have one.

 

[bob06]

This is way different than your 124 but you can see the springs on my motor mounts that replaces the stock bushings.

 

[setup1]

Thank you, still learning.
I have read through a lot of the rebuild material on theanalogdept website. Do you think that it's safe to assume I will have to break apart the motor and clean given 1958 manufacture and non-use for 30+ years?
What is the group's preferred source for new bushings, oil, other parts?

I'd recommend that you give the motor a thorough cleaning. Back in the early 90s I acquired a TD124 Mk I that was stored for many years. The motor won't even spin but after cleaning it up, the unit worked beautifully and quietly on its original belt and idler. I just serviced that same turntable last year but the motor is still running on original bushings/bearings. As for oil, I've always used left overs from an oil change, right now my car uses 0W-20.

If you decide to use your ROK S120 tonearm, here are some tips.

That's a mighty fine heirloom you've got. Good luck and happy listening!

 

[bhamham]

Bhamham, there are a couple of sources from Moldova that I see on eBay for built up plinths. Do you recall who you got yours from?

'valeriabond' is the ebay ID. If you don't see a specific one you want, message him and ask. They can probably make it. It was around two months before I got mine.

 

[Slack73]

Thank you, still learning.

I have read through a lot of the rebuild material on theanalogdept website. Do you think that it's safe to assume I will have to break apart the motor and clean given 1958 manufacture and non-use for 30+ years?

What is the group's preferred source for new bushings, oil, other parts?

I second setup1's advice to try cleaning everything first. Unfortunately in my case, the motor on the one i have here was seized beyond cleaning.

Look for "audiosilente" on Ebay for bushings / rebuild kit if needed. I haven't had a chance to install mine yet, so i can't 100% attest to the quality. I feel pretty confident though based on their feedback and sales.

 

[guiller]

I second setup1's advice to try cleaning everything first. Unfortunately in my case, the motor on the one i have here was seized beyond cleaning.

Look for "audiosilente" on Ebay for bushings / rebuild kit if needed. I haven't had a chance to install mine yet, so i can't 100% attest to the quality. I feel pretty confident though based on their feedback and sales.

I endorse the Audiosilente parts as well.

 

[tromba]

Buying a plinth is certainly the easiest way to go. If you have woodworking skills (or like me have a friend with woodworking skills) here's a photo story of building my plinth for my TD-124

 

[TD John]

Buying a plinth is certainly the easiest way to go. If you have woodworking skills (or like me have a friend with woodworking skills) here's a photo story of building my plinth for my TD-124

Thanks so much for this - this will help a lot. Sorry I didn't come up with this in my search.

 

[heyraz]

This is about my motor rebuild.
Not sure where my posts about the main spindle bushings are.

https://audiokarma.org/forums/index...p-and-rpm-drops-is-the-belt-too-tight.751269/

 

[Lapslah]

1. Don't separate platter from spindle unless absolutely necessary. Thorens used a special internal jig to center the inside surface where the idler wheel contacts the platter at the factory.

I'm in the minority around here on this one, but I disagree. This myth (in my opinion) got started when somebody saw an old photo that's been circulating forever of Thorens techs using a run-out gauge on the platter/spindle assembly and jumped to the conclusion that they need to be centered relative to one another upon assembly - every time. But if you look at the way they actually go together, the spindle fits snugly in the center hole of the platter - enough so that when you unscrew the 3 flat fillister screws it's still difficult to pull the two pieces apart. Now tell me, how can two round pieces that fit together snugly at their center points be adjusted for concentricity? I believe that the photo shows either quality control or initial centering of the two parts prior to drilling the center holes. Once those holes were drilled, you couldn't get them to be non-concentric if you tried. I've had my TD124 in my main rig for going on 20 years. When I first got it I read that you should always remove the platter from the spindle because reinserting the spindle into the well with the added weight of the heavy iron platter risks causing a leak in the seal. In that time, I've pulled them apart more times than I can count and they have never shown any visible or audible signs of being out of round. BTW, I've consulted multiple engineers on this and they have all agreed with my assessment.

 

[matt e.]

You should familiarize yourself with the Thorens Overhaul Guide written by Joel Boutreux formerly of Thorens. He offers great insight based on his years of experience. Mobil Velocite Spindle Oil #6 (10weight) is recommended by Linn. Velocite #10 (22weight) may be more appropriate for TD124's, but it all depends on the bearing clearance and wear of your machine. If you can run the lower viscosity oil without noise issues then you will have less wear and tear on the motor and bearings.

Edit: Ideally it would be nice to buy a small assortment of #6, #8, and #10 to experiment with, but unfortunately Mobil sells it in one or five gallon containers.

 

[matt e.]

I'm in the minority around here on this one, but I disagree. This myth (in my opinion) got started when somebody saw an old photo that's been circulating forever of Thorens techs using a run-out gauge on the platter/spindle assembly and jumped to the conclusion that they need to be centered relative to one another upon assembly - every time. But if you look at the way they actually go together, the spindle fits snugly in the center hole of the platter - enough so that when you unscrew the 3 flat fillister screws it's still difficult to pull the two pieces apart. Now tell me, how can two round pieces that fit together snugly at their center points be adjusted for concentricity? I believe that the photo shows either quality control or initial centering of the two parts prior to drilling the center holes. Once those holes were drilled, you couldn't get them to be non-concentric if you tried. I've had my TD124 in my main rig for going on 20 years. When I first got it I read that you should always remove the platter from the spindle because reinserting the spindle into the well with the added weight of the heavy iron platter risks causing a leak in the seal. In that time, I've pulled them apart more times than I can count and they have never shown any visible or audible signs of being out or round. BTW, I've consulted multiple engineers on this and they have all agreed with my assessment.

I read that you couldn't check it from the outside with a dial indicator because the inside surface wasn't necessarily parallel with the outside. Unless the platter is bent I can't see that as an issue on the little TD134 platter. Maybe on the big cast platter of the 124, but not the 134. The holes that attach the TD134 platter with the bearing hub definitely will allow some movement. Before I call it done I am going to put a dial indicator on it and set for least runout.

 

[matt e.]

I'm in the minority around here on this one, but I disagree. This myth (in my opinion) got started when somebody saw an old photo that's been circulating forever of Thorens techs using a run-out gauge on the platter/spindle assembly and jumped to the conclusion that they need to be centered relative to one another upon assembly - every time. But if you look at the way they actually go together, the spindle fits snugly in the center hole of the platter - enough so that when you unscrew the 3 flat fillister screws it's still difficult to pull the two pieces apart. Now tell me, how can two round pieces that fit together snugly at their center points be adjusted for concentricity? I believe that the photo shows either quality control or initial centering of the two parts prior to drilling the center holes. Once those holes were drilled, you couldn't get them to be non-concentric if you tried. I've had my TD124 in my main rig for going on 20 years. When I first got it I read that you should always remove the platter from the spindle because reinserting the spindle into the well with the added weight of the heavy iron platter risks causing a leak in the seal. In that time, I've pulled them apart more times than I can count and they have never shown any visible or audible signs of being out of round. BTW, I've consulted multiple engineers on this and they have all agreed with my assessment.

Perhaps it should be marked so that it is reassembled in the same 3 holes just in case any runout errors were compensated when it was originally assembled.

 

[TD John]

Buying a plinth is certainly the easiest way to go. If you have woodworking skills (or like me have a friend with woodworking skills) here's a photo story of building my plinth for my TD-124

Tromba, thank you so much for the link within the link to the long and very exhaustive thread on plinths. It took a while to get through all of that information but upon reading it, then returning to your own plinth build, it put it all in greater perspective.

Two questions, did you follow through on the thought to mount the motor to the plinth? I gather from your photos that you ended up leaving it mounted to the frame. I thought the idea of isolating the motor vibration from the frame / platter / arm probably had merit, but perhaps I was wrong in that assumption.

Also, did you end up going with the original mushroom mounts, or did you modify the way the frame sits on the plinth in some way? I remember reading of at least these: using springs, different rubber, silicone, mounting direct / hard to the plinth.

Thanks again for all the info from all of you.

 

[Lapslah]

Perhaps it should be marked so that it is reassembled in the same 3 holes just in case any runout errors were compensated when it was originally assembled.

If the center hole as truly in the center (as I believe it is), it shouldn't matter. Not to mention, if the 3 screw holes are not symmetric, you'd have a hard time assembling it "wrong".

 

[matt e.]

If the center hole as truly in the center (as I believe it is), it shouldn't matter. Not to mention, if the 3 screw holes are not symmetric, you'd have a hard time assembling it "wrong".

I pulled the aluminum platter off one of my TD124's and I agree. Would be pretty much impossible to get it wrong. If it has runout it has been dropped or dropped upon. Thanks for clearing up that misconception. I think the TD124 platter alone weighs about twice what the TD134 does in its entirety. Curious as to why Garrard was able to so totally outsell the 134 in the consumer market. Can only guess it was the RC thing.

One of my 124's is an early serial number and has nylatron bushings. I bought a set of oilite bushings from the guy in Spain. I know they will have to be honed for clearance after pressing. With the proper hones is this a job I should consider doing myself? Taking the spindle off the platter would be necessary, but now I feel much better about doing that.

 

[bob06]

Tromba, thank you so much for the link within the link to the long and very exhaustive thread on plinths. It took a while to get through all of that information but upon reading it, then returning to your own plinth build, it put it all in greater perspective.

Two questions, did you follow through on the thought to mount the motor to the plinth? I gather from your photos that you ended up leaving it mounted to the frame. I thought the idea of isolating the motor vibration from the frame / platter / arm probably had merit, but perhaps I was wrong in that assumption.

Also, did you end up going with the original mushroom mounts, or did you modify the way the frame sits on the plinth in some way? I remember reading of at least these: using springs, different rubber, silicone, mounting direct / hard to the plinth.

Thanks again for all the info from all of you.

There's only one person that I know of that successfully mounted a 124 motor to the plinth. And that's me.