Tonearms without anti-skate, damage to records?

What about damage to the cantilever as well as the record groove.

Better off with a tangential tracking arm, no skating forces, no groove damage and no damage to the cantilever suspension from incorrect antiskate application.

But The skating force is not linear in the way its magnitude varies. In that respect Magnetic AS might be inferior to a weight on a string, at least the latter is more or less constant with respect to the magnitude of the AS force. 

For me I prefer weight on a string for 2 reasons -

You can measure the anti-skate accurately

I tend to use very little anti-skate - somewhere between 25 & 30% of the tracking force as recommended by Shure, Grade & van den hul. Many sprung or magnetic antiskate mechanisms cannot get that low with any precision.

@dover   Please explain why you think the skating force does not change linearly as the record is played.  Surely it is just a question of geometry?

I never said that.

On a linear tracking arm there is no skating force.

On a pivoted arm it varies across the record.

unfortunately, not true for straight line trackers because of the very high horizontal effective mass. The stylus and cantilever have to drag this along and even with an air bearing you can observe the cantilever deflecting and if level is not dead on it can be a real battle. 

@mijostyn 

Whilst I agree with high horizontal mass being not ideal, in reality the lateral forces on the cantilever are still lower than a pivoted arm - this is documented on the Eminent Technology website.

In fact here is an explanation from Bruce Thigpen himself

The untold parameter of a pivoted tonearm: To minimize tracking
error, pivoted tonearms were lengthened with a bend in the wand, or by
mounting the stylus at an angle in the headshell. The frictional force
of the stylus in the groove wants to straighten out the bend or crawl up
the records inner groove wall. When using anti skating with a pivoted
tonearm to prevent inner groove wear, regardless of mass, pivoted
tonearms bend the stylus with an opposite side load force of between .1
and .2 grams per gram of tracking force, the tonearm shaft is being
twisted outward (as viewed from above) with this static load which goes
through the stylus suspension, but the percentage of creep on the inner
wall of the record groove actually varies with the passage loudness or %
groove modulation. So you are constantly bending the stylus while only
marginally solving the problem.

With the ET-2 the side loads to accelerate the tonearm at .55hz
(33/13 RPM) are less than half of those values for an eccentricity of
.0312 inches (1/32 inch) and are a linear function of record
eccentricity. The cartridge cantilever suspension sees much lower loads.

So as you add mass, this side load value of the ET-2 goes up
linearly, but is always less than using any pivoted tonearm with anti
skating.

As an example I ran a high compliance Shure V15vmr ( with stabiliser removed ) in the ET2 for 10 years without changing the stylus. The cantilever was still dead straight after 10 years. The only significant mod I did to the ET2 was to run magnetic damping for the horizontal movement using eddy currents.

@rsf507

@dover I prefer weight on a string 

Can you explain how you determine the 25 - 30% via this method?

Yes - you can use scales to measure the actual falling weight, it won't be exact because there will be some loss due to the mechanism ( usually friction ). However it is more accurate than most sprung or magnetic antiskate mechanisms.

2 examples - 

FR64S - this has markings on a pivoted rod that you slide the weight along that denote 0.5g increments in antiskate.  I actually measured using strain gauge scales the falling weight at each increment and was surprised to find the markings very accurate. Measuring the falling weight ( with the platter removed ) at various points across the record showed very little if any deviation as the rod went off horizontal.

With this arm I set the arm up such that the rod that the weight sits on is horizontal at the mid point of the record ( to minimise deviation ) - seems to work well.

Kuzma 4point - recently installed a van den hul Grand Cru with a specified antiskate force recommended by van den hul of around 0.2g - the only way I could achieve a level this low was to use a piece of bluetack carefully trimmed and measured on stylus scales instead of the metal weight - even Franc's custom small weight could not get this low. 

 I have generally found that a very tiny amount of AS, usually much less than textbook, suffices to alleviate the distortion, and that’s where I stop, but not at zero AS.

Spot on - from my personal conversations with both Brian & John Garrot ( orig Garrots Bros ) and AJ van den hul most cartridges come in with uneven wear from incorrectly applied antiskate ( or none ). This is from truckloads of cartridges sent for rebuild.

The top van den hul cartridges all now come with recommended antiskate levels specified - individually calibrated for each cartridge.

In the old days (80's onwards) most shops used to recommend anti skate up to 75% of the tracking force - this is too high.

Both Shure and Grado with extensive testing came up with recommended levels between 25-30% - much lower than most shops recommend.

I can easily hear changes to antiskate in my system.