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View Full Version : Thorens TT Lift arm .. help?



danilo
28-05-2016, 20:27
My bought new Td 150 mk2, over the decades had developed a Verrry slow arm drop.
When it devolved to taking ~20 seconds to hit the LP... I decided to fix it.
Soooo I lightly oiled it (bottom off adventure) No disassembly though. Immediately the Lag was gone.
Lift dropped instantly Bounce the needle instantly. Toooo fast imo.
Lived with it for a decade or so, albeit I rarely played my LPs in the interim.
Today I decided to revisit it.
Disassembled the Lift Contraption entirely and to my chagrin, I found Zero damping inbuilt .
Just a stoopid/simple rod in a bore. No silicone, no chamber, no o rings , no seals, no valves ..Nada.. Nothing at all.
Seemingly not even any attempt at it

Sooo... Am I correct in assuming that Congealed oil residue is the only working damping on these contraptions?
PS; did refit with Phils' Tenacious oil as experiment (Hypoid oil sans the Sulphur smells, thick as molasses )
No noticeable difference.
I see that My version Lift is fitted to a series of Thorens TTs.
Are these All like that then ?
Just yesterday binned an old Cheap Automatic TT that had irrevocably seized from decades of Non use.
Even ..It, had a very nicely made Lift/drop damping device, a wee shock absorber thing which still worked.
Never ocurred that my Thorens was lacking such entirely. Or I would have salvaged it.

Hopefully I've missed something Basic and there IS a simple 'fix' ??

struth
28-05-2016, 20:41
is it a thorens arm? think they used springs if memory serves... 3 of them.

danilo
28-05-2016, 21:08
Yup Oem... tp13A I believe.
TT is virginal.
Yes there are springs, All operable, and in their correct (as mfg'd) locations.
The springs seem to allow/enable the mechanical monkey motions to be smooth and replicable.
However they 'seem' to be completely independent of the lift rod sliding back down it's bore.
Good thought .. thanks.. it gave me pause.

Just had an ugly thought. Swiss (West German) Lunatics 'may' have built an interference fit to the lift rod... to ensure friction for Ersatz damping action.
Could be tricky to find a 'Knurler' in that bore size.
Possibly copper plate the rod to increase it's diameter. Possible solutions, seeming as a PITA though.
Surely I can't be the Only twit with a Geriatric Thorens ??

Arm from a Techie 1200 a worthwhile retrofit ?
Not keen on an arm refit (lazy :-)
However I do have one in a baggie. Seems as a surprisingly Heavy contraption when hefted,
which is why I've not done so.. additional to the above Lazy bit..

danilo
28-05-2016, 21:15
No idea re the triple posting :scratch:

danilo
28-05-2016, 21:21
Sigh..

rdpx
28-05-2016, 23:03
Can't you just refit a different arm drop bit? A lot of people fit sme arms, which would suggest there are a lot of spare Thorens parts knocking about at the back of drawers... I've got the same tt and my arm drop works just fine.

Sent from my GT-I9195 using Tapatalk

danilo
29-05-2016, 02:39
Seemingly I needs find some THICK sillycone grease 300,000 csT apparently and apply it to the lift rod/fill the wee receptacle.. which allegedly slooows down the Lift drop, nicely.
The intricacies of Thorens Lore.
Hopefully that helps someone else as well.

danilo
29-05-2016, 02:54
Found some Silicone Dielectric grease in my toolbox.
Used it in lieu of having any of the Real stuff. It works ! 3 to 4 second drop time.
Inevitably it will become longer as the stuff dries out.