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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

Showing 2 responses by dover

dover
2,299 posts
 
@IsfarzoI 

I have compared your pictures to my own SME - to me it appears the aftermarket knife edge bearings are not correct - the knife edges are too high, resulting in the armtube sitting too low in the carrier.

Since you appear to have the armlift as low as possible, cartridge spacers &/or adjusting the back of the arm cannot fix your problem.

I think you need to replace the knife edge bearing.

dover
2,299 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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