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help with clearance between sme 3009 arm's tube and arms lifter assembly

Hello guys,
I’m writing to ask for your support to correctly couple a Thorens TD160B mk 2 with a a SME 3009 improved seried 2 removable headshell arm. The cartridge I use is a Benz ACE L.

I bought the arm’s base and mounted the arm, verified its null points with the protractor, regulated the pickup orientation and put the cartridge shell parallel to the LP surface with an LP on the mat.

So far so good.

The point with me is that the clearance between the arm lifter assembly and the arm tube: it is too short. When putting the cartridge on the LP the arm tube touches the arm lifter (the semi-arc on top of the lifter case) and so it the stylus does not touch the LP at all.

I know (or at least I think I know) all about the exagonal 1/16’’ screw to be unscrewed to rise/lower the arm’s pillar and the other to untighten and rotate the arm lifter ring. So, I screwed the hex screw to rotate the arm lifter ring to the lowest point of the thread which below the arm’s yoke, on top of the arm’s pillar, but the clearance between the arm’s tube and the lifter is still too small to any avoid contact between these two parts.

With that said, now I run out of ideas.

Images at: 
https://imgur.com/zNxfC1p
https://imgur.com/qx0x6TG
https://imgur.com/GVeJjj4
https://imgur.com/KcAhhLG

Please, is there anybody out there ( ) who already run into this problem and who is so kind to help me ?

An additional info: in order to correctly set the arm pillar height (it affect the VTA...) I put a small inclinometer on the top of the cartridge shell and adjusted the height of the pillar until the cartridge shell was parallel to the disc surface. Is it correct ? I think so, but prefer to ask.

Many thanks
Luca
lsfarzo
lsfarzo OP
5 posts
 
 sorry ALL of you for the late response but I was at work.
I read very very carefully all of your posts which helped me to better understand the current situation.

Yes the arm was rebuilt and has the brass knife (also rewired with vey nice VDH cable...) .
Anyway, to see if there was any difference in rising the arm with the former plastic knife I re mounted the old knife but find out that the clearance is still exactly the same as with the bronze knife. So this was not the cause of the problem.

Concerning the question if the arm hits the rubber or the metal case of the lifter... it depends how high it is mounted !
The arm sits on the rubber on the lifter if I exactly mount the headshell parallel to a LP surface, and it hits also the outer edge of the metal case of the lifter in case I eliminate the rubber semi arc and lower a little the arm... 

So... the current sad situation is that I am to put out the rubber semi ring on top of the lifter and give up to a "hopefully" perfect VTA, mounting the arm at an height which is a little lower than the best, so that the clearance between the arm's tube and the lifter edge is sufficient to play LPs.

Personally, I do not like this but can't see more choices...  anyway it still looks to me very strange even because, looking at your photos the installation looks very neat and simple !

Luca




lsfarzo OP
5 posts
 
@cleeds by my photos you should see the armboard...

Luca

Ag insider logo xs@2x
cleeds
6,029 posts
 
lsfarzo
... by my photos you should see the armboard...
Yes, I do see that now, @lsfarzo.. Wouldn’t a thicker armboard be your solution? It would raise the arm height, which would allow you to lower the arm pillar.
mijostyn's avatar
mijostyn
8,570 posts
 
OK Luca, there is one other solution but this one is a little tricky. If you were to bend the head shell just a little downwards at the front this with increase the VTA a little allowing you to lower the back of the arm giving more clearance but allowing you to keep the head shell parallel to the record. The metal is soft. I would take it off the tonearm and put the plug in a vice. It has to be bent symmetrical and just a degree or two. Worse case scenario is you'll need to get a new head shell. You could do worse.  
dover
2,265 posts
 
@Isfarzo

 If I look at photo 4 it appears the gap between underside of the top of the yoke and the bronze piece looks about the same as the gap between the bottom of the armtube and the bottom half of the yoke.

This suggests the arm is too low.

On my SME the gap at the bottom is about twice that of the gap at the top.
Actual measurements -
Physical gap between top of tube including the knife edge and the yoke 3/32" approx 2mm
Physical gap between bottom of tube and yoke 6/32" approx 4mm

Another check - the bottom of the armtube in mine is inline with the bottom edge of the top half of the yoke ( looking side on below the screw ).

Unless its an optical illusion your armtube looks too low.

If thats the case there are only 3 options -
Knife edges too high
V cuts n the bottom half of the yoke have been recut and are now too low
Is your armtube original.

There is one other possibility - if the pillar bearings have been replaced and aren't deep enough, then the arm/yoke would be sitting too low relative to the armlift. However, from the pictures I cant see anything to suggest this.

Finally - is the pillar bearing assembly/armlift original ? Maybe someone has mismatched the armtube assembly and arm pillar bearing assembly ??


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