Is Anti-skate > 0 even with the A/S mechanism disabled?

[ckniker]

Should a Triplanar apply a slight amount of anti-skate even with the anti-skate thread completely removed?

I swapped cartridges over the weekend so I had to go through a cartridge alignment all over again.

In the process of setting up my Zyx UNIverse with a MintLP Protractor, I was getting a fair amount of anti-skate applied. The A/S force was much greater when closer to the spindle and caused the cartridge to slide a small distance across the glass surface of the protractor.

This was done with the following setup conditions:

1) the Triplanar A/S thread was removed
2) VTF set at around 1.9 grams
3) the turntable platter was leveled (with a bubble level)

I have noticed in the past that my cartridge's cantilever shifts outward when it rests on the protractor surface (even with zero A/S applied). I always thought it might be an idiosyncracy in the cartridge's suspension. With the additional observation from above, I now believe it's a confirmation that a small amount of A/S is being applied by default.

I haven't done enough research to know whether this is a known design intent.

Is there something wrong with my Triplanar? As far as I know it's the latest iteration (Mk VII version u?).

[jfd01]

I don't know if there's something "wrong" with your Tri-Planar, but I haven't experienced that problem with mine (maybe there's something wrong with mine?).
I recently re-aligned my Universe with the MintLP protractor (for various reasons, I've been doing this a lot lately...), and that time I had actually forgotten to take the AS weights out (I use o-rings, not the weight): there was no pull on the arm. When I've aligned without any AS weight before, I never had the cart slide, at eany position on the protractor; same thing with my Airy 3.
just my 2 c.
Cheers,
Joel

[galibier_numero_un]

I wonder if your armboard and platter are both level?

Edit (3/29/09): Meaning - is your Teres armboard parallel to the platter (knowing that the platter is level from your first post)?

Cheers,
Thom

[Dan_ed]

Chris,

My arm has a small, abrasive patch stuck to the bottom of the arm where it sits on the cue. Does your arm have that stick on patch?

[ckniker]

My arm has a small, abrasive patch stuck to the bottom of the arm where it sits on the cue. Does your arm have that stick on patch?

Yes, my Triplanar has the abrasive patch on the underside of the arm.

is your Teres armboard parallel to the platter (knowing that the platter is level from your first post)?

My (inexpensive) bubble level seems to indicate that they're pretty close to being parallel. I don't think it would pass a NASA test but I'd guess it's within an acceptable amount not to be influenced by the amount of anti-skate I'm experiencing.

I take it, Thom, that this is a little surprising...

[galibier_numero_un]

My (inexpensive) bubble level seems to indicate that they're pretty close to being parallel. I don't think it would pass a NASA test but I'd guess it's within an acceptable amount not to be influenced by the amount of anti-skate I'm experiencing.

I take it, Thom, that this is a little surprising...

Nothing surprises me. It's hell to maintain quality - even with a machinist you've been working with for years. The fact that everything is made of wood makes the process all the more difficult.

"Pretty close" ... I don't know what to make of that, or its influence on what you're observing. Inexpensive bubble levels (the linear kind, and NOT the small disk shaped ones) are fine for pivoted tonearms. With linear trackers, it's a whole 'nuther story, but the arm itself serves as the level in this case.

How does the arm behave when "floating" above the playing surface - with no anti-skate and a zero tracking force? Does it more or less "hang" in space?

Thom

[ckniker]

How does the arm behave when "floating" above the playing surface... ?

Good question, Thom.

I'll need to take a closer look and get back to you.

Incidentally, the level I used was a "disk shaped one". I put this on 1) the platter and 2) the surface of my armboard. The level wasn't EXACTLY in the same spot for both but they were "Pretty close". I guess I should be striving for spot-on accuracy for the purpose of this analysis (to rule that out as a problem).

I'm not sure why you say a disk-shaped level shouldn't be used here (or are you speaking about something different?)....

RE: made of wood

I guess this is another good reason to investigate using a Stelvio armboard on my Teres. See my other note in the Couloir (spelling?).

Chris

[eweitzman]

Bubble levels vary widely in accuracy and precision. A ten dollar "bullseye" (or disk-shaped?) level is normally highly inaccurate. It can read the same on two non-parallel surfaces.

- Eric

BTW, I use a a 4' framing level, a 2-ton floor jack, and wooden shims to level my table.

[ckniker]

Just realized that I failed to update the board on my findings with regard to this subject:

It turns out that the surface of my (Teres 320) armboard is not EXACTLY level with the surface of my platter. Because I use the platter surface to level the table, the armboard is not level.

As a result, the cartridge is being pulled by the different plane that the Triplanar is mounted on (and the near-frictionless bearings in the Triplanar are being nudged by the slight deviation from level).

Chris