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Thorens 150 Mk II Rt. Front Spring Tuning?

I'm sorry, but this is even more confusing. Who said the spring studs should be level? Do you mean plumb?

At any rate, as already mentioned above, this applies more to the LP12 than the TD-150 and I'm sorry I brought it up.
 
I'm not a plumber. I only own levels and squares.

if the plate is horizontal, the studs must be 90 degrees to it, so perfectly vertical.
 
ddarch said:
Stock Thorens belt? (Or Thakker?) That's key.

D
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It's an aftermarket belt, but I have it dialed in at 33.33 rpm, so I doubt it is out of spec in any way. In my experience, belts out of spec in any dimension by microns affect the speed in startling ways. Frankly, yeh, the right front spring acts as if the belt is too tense, but I can't imagine that a non-spec belt would provide 33.33 rpm. Also Dean Man reflected the advice to turn the springs' "base points to the platter bearing." Someone else--I think it is the maker of the replacement spring kit (mine still has the original springs, again)--said turn the "strong side" of each spring toward center, and I did this, to no effect on my attempts to tune the 150 so that all springs bounce vertically.
 
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plbeard said:
It's an aftermarket belt, but I have it dialed in at 33.33 rpm, so I doubt it is out of spec in any way. In my experience, belts out of spec in any dimension by microns affect the speed in startling ways. Frankly, yeh, the right front spring acts as if the belt is too tense, but I can't imagine that a non-spec belt would provide 33.33 rpm. Also Dean Man reflected the advice to turn the springs' "base points to the platter bearing." Someone else--I think it is the maker of the replacement spring kit (mine still has the original springs, again)--said turn the "strong side" of each spring toward center, and I did this, to no effect on my attempts to tune the 150 so that all springs bounce vertically.
Click to expand...

Whether "strong side" or "base point side" the goal is to start in somewhat the same place. Inevitably, one or more springs will need to be twisted. What you are describing could also be attributed to the single spring on the left side...twist that one so it's placing more resistance against the tendency to pull toward the motor. d
 
I'll confirm: what is crucial is the belt. Even though I had a belt that spun at 33.33,
somehow it was, by a tiny-but-significant amount, too tight, and tended to tug the tonearm's
platform slightly toward the center and (at the front) against the chassis.
Cure: a real Thorens belt. I didn't have to re-adjust anything else:
I saw the whole thing bounce evenly, vertically, correctly with the real Thorens belt.
 
plbeard said:
It's an aftermarket belt, but I have it dialed in at 33.33 rpm, so I doubt it is out of spec in any way. In my experience, belts out of spec in any dimension by microns affect the speed in startling ways. Frankly, yeh, the right front spring acts as if the belt is too tense, but I can't imagine that a non-spec belt would provide 33.33 rpm. Also Dean Man reflected the advice to turn the springs' "base points to the platter bearing." Someone else--I think it is the maker of the replacement spring kit (mine still has the original springs, again)--said turn the "strong side" of each spring toward center, and I did this, to no effect on my attempts to tune the 150 so that all springs bounce vertically.
Click to expand...

For what it’s worth, I recently tuned my TD 150 MkI and replacing the old belt with a new Thorens belt did the trick. The old belt was an original Thorens too, but maybe it was a bit worn out. I’m not getting the same bounce as my TD160 (15 seconds or so) but at least I got it to bounce evenly. is it even important to get a prolonged “bounce” with these Thorens decks? Anyway, in my case, the left spring was pretty much uncompressed. The spring nearest the tonearm was the most compressed and the right spring a teeny bit more compressed than the left. A lot of twisting and turning to the left most spring finally got the whole platter to bounce evenly. Pretty much trial and error I guess. Good luck and hope you get it right soon!
 
mdc701 said:
Good luck and hope you get it right soon!
Click to expand...
All good, yes: this 150 Mk. II is speed correct (and actually was previously, with the "too tight" belt)
but what is critical (or what slightly annoyed me--it is debatable if that is "critical")
is that the tonearm platform is now independent of any rubbing against the chassis,
although, in an "if it ain't broke, live with it" spirit (see the dates of the these posts),
I Let It Be for awhile: My 150 Mk II turntable tolerated that friction with spec. speed and wow numbers.
But now, with the new belt, it has both excellent numbers and bounces free of the chassis.

P.S. These TT's have great build quality, but their design is slightly inferior to the AR XA turntable, which at this point, I think, Thorens were trying to imitate without infringing on AR's patent. (That is, the platform for the tonearm is a design inferior to the AR XA, but if you have this TT the whole can be made to bounce correctly.)
 
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