SME V arm: dynamic VTF or straight weight

Hi Albert,
That is interesting. When I loosen the set-screws at the base of the arm, I can tilt the cylindrical arm post slightly to the left or right. I had thought this was a way to adjust azimuth before tightening the screws again. Then a read a post by dougdeacon that this was not a good idea because the bearing would then not be level if the arm post were not vertical or plumb. That got me thinking that if the arm post is not truely vertical, or plumb, then all the rest of the geometry as the arm swings toward the LP center is not correct either. So now I check for level with a bubble level placed on the flat surface to the arm lock which I assume is perpendicular to the arm post. When it is level, I then retighten the setscrews. Is this slight play in the arm post not normal?

The issue with the VTA screw is that it is off-center from the pivot point so as it is turned clockwise to raise the arm, it exerts a force which tilts the arm slightly to the right as viewed from the front. I then tilt it back by pushing the bottom of the post to the right, moving the top back to the left and making it true vertical again. I thought all SME arms had this slight play at the base.

I now agree with all of those people who say that azimuth is not adjustable on the SME arms because the post has to remain truely vertical or plumb. Fortunately, my PC-1 cantilever is "perfectly" straight and centered in the vertical plane.

This thread is getting off the topic of dynamic vs. static VTF and becoming more about adjusting the SME V arm. Perhaps a topic for another thread. Sorry.

Peter,

The SME 312S has removable head shell, so the collet may be loosened and the head shell twisted to obtain proper azimuth. Once set I've loosened the post in the rear to change VTA and never experienced any "shift" in azimuth after raising or lowering the arm.

Hi Peterayer

>>> The biggest problem with the SME V design is the difficulty of adjusting height. Every time I try it, the arm column moves slightly out of vertical because the VTA screw is off centre and I have to recheck azimuth <<<

My solution:
Make some hardwood spacers (small oblong blocks) fit between armrest and clamping assembly, loosen the bolts press down on the pivot bearing-bridge. The arm will ALWAYS be level with the spacer block. I have made these according to VTA requirement. I started somewhere from 1/2" which fits for a Windfeld. If the PC-1 is by X taller this must be added.
You can achieve quite easily the small differences Raul is talking about --- AND HE IS RIGHT THERE --- a 0.3mm difference can just make that difference to be more pleasing.

Greetings,
Axel

Alex,
Thank you for that suggestion. It makes sense.

Hi all,
one thing came to mind when reading about silicone damping being considered a 'crutch' to make up for lack of arm to cart matching ---- but wait, there are arms that use 'damping' a their required part of operation!
Well Tempered (now a golf ball! in silicon), Schroeder uses a magnet, just to mention two. Others consider it an 'option' but actually seem to sound more 'right' with juice in their various bowls, I'm thinking of uni-pivoted designs.

Are these all aberrations to some 'true teaching' , I can not see that, honestly.

Back to the V damping trough, (an option with the less expensive IV, IV.vi, and 300 series). If you have a V, and feel like some purists, and want to remove it --- it leaves the arm with a rather unbalanced looking uncovered left side horizontal pivot bearing...
I listened with that 'hard wear' on and off --- ZERO difference.
I might mention it is not quite that easy to take it off in the first place, since it it VERY solidly bolted on, with some part catching under some other cover. Just before you get the idea.

Axel