How do tell when my stylus is too much worn?

@aspens  Thank you for sharing your paper. It was a very interesting read with attention to detail and acknowledgements. 
My initial reaction is ”that reminds me why I used to buy MM". Installing a new stylus is a piece of cake, of course if they are still being produced. Through this forum, @chakster , @rauliruegas and others, I've recently purchased and have been using a Stanton 881S with D81 Stereohedron stylus. As you know those stylus are no longer being produced so I was lucky to get a low hour example. As your paper points out VTF contributes to stylus wear, amazingly enough the Stanton high compliance cartridges spec is from 0.75 grams to 1.25 grams. Mine is set to 1 gram which is much lighter than a typical modern production specification for a cartridge. Your paper points out at least 20% longer life for a lighter VTF, and it seems that the high compliance cartridges of the past were leaning towards the lighter VTF, which also result in longer stylus life. 

@captain_winters 

Stanton 881S with D81 Stereohedron stylus. As you know those stylus are no longer being produced so I was lucky to get a low hour example. As your paper points out VTF contributes to stylus wear, amazingly enough the Stanton high compliance cartridges spec is from 0.75 grams to 1.25 grams.

Great cartridge and amazing stylus profile, i love Stereohedron! 

Pickering D-3000 Stereohedron is also compatible with your Stanton 881, asctually your Stanton based on Pickering XSV-3000 model. I have a NOS factory sealed D3000 Stereohedron stylus if you need a backup. 

For both Stanton and Pickering the optmal setting of VTF with brush is:

Arm setting with brush: 2 grams +/- 1/4
Resulting tracking force: 1 gram +/- 1/4
Arm setting without brush: 1 gram +/- 1/4

Norman Pickering was a noted violinist. He invented the Pickering cartridge because he didn't like how violins sounded on other cartridges. So, he is thus far one of the cartridge designers in the USA besides Joe Grado who was also a musician. Pickering's factory manager was none other than Walter Stanton, who later went out on his own. By 1960, Mr.Stanton bought out Mr.Pickering. He later established Stanton Magnetics Inc in 1961. He was the chairman and president of both Pickering & Co and Stanton Magnetics Inc until 1998. Walter O. Stanton, the inventor of an easily replaceable phonograph stylus that was crucial to creating a consumer market for audio equipment. Stanton and Pickering carts are the same with interchangeable styli despite the very different looking plastic bits and brushes - the trick is figuring out the interchanging model numbers. Pickering XSV-3000 is equal to Stanton 881s, both comes with Nude Stereohedron diamonds on alluminum cantilevers. This is the most advanced stylus shape which is achieved by grinding four flat surface on the diamond at precise angles to each other and their intersection creates areas used to contact the groove. The advantage of the Stereohedron stylus is that because of it's long and narrow contact surfaces it tracks high frequency modulation minimizing groove wear.

Norman C. Pickering, an engineer, inventor and musician whose pursuit of audio clarity and beauty helped make phonograph records and musical instruments sound better. In 1945, Mr. Pickering, who enjoyed listening to records and was frustrated by the sound quality of recordings, developed an improved pickup — that is, the mechanism that includes the phonograph needle, or stylus, and translates the information in the groove of a record into an electrical signal that can be reproduced as sound. Originally His phono pickups were designed for use in broadcast and recording studios. 1947 the demand from high-fidelity fanatics was strong enough for what’s now called a ‘cartridge’ and Pickering & Company was formed to meet the new hobby’s demands. In 1948, Mr. Pickering was among the founders of the Audio Engineering Society, now an international organization that disseminates news and information about improvements in audio technology. By the mid 50's, the Pickering company employed more than 150 people at its Plainview, Long Island headquarters. The best models, however, were introduced only in the 70's and early 80's. Pickering XSV-3000 with nude Stereohedron stylus is one of the best, a few models with higher numbers are even better.

Pickering XSV-3000 specs:

Stylus Type: Nude Stereohedron
Contact Radii: .0028 (71u)
Scanning Radii: .0003 (8u)
Stylus Tracking Force: 1 gram (+/- 0.5)
Setting with Brush: 2 gram (+/- 0.5) resulting operation tracking force 1 gram (+/- 0.5)
Frequency Response: 10 Hz to 30 kHz +
Output: 4.7 mv /cm/sec
Channel Balance: Within 1 dB @ 1kHz
Channel Separation: 35 dB @ 1kHz
Cartridge DC Resistance: 700. ohms
Cartridge Inductance: 350 mH
Cartridge Color: Brown
Load Resistance: 47k ohms or greater
Load Capacitance: 275 pF  

Dear @aspens  : Ortofon published its scientific research about in its site and suddenly dissapeared but was there where for the very first time I learned that at 500 hours of play the stylus tip will starts to make damages in the LP records even that we can't be aware of that damage.

In those all times I posted several times that any cartridge must be rettiped as long as 800 hours of playing time or maximum 1K and every body told me that's was a " crazy " statement because the manufacturers states at least 2K and so no one cares really about.

Not many time ago a gentleman with a Lyra Atlas started a thread because his cartridge was not running with the excellent quality performance he was accustom to. Many Agoners posted their opinions what he needs to do to try fix the problems. 
His cartridge was over 1K hours and I posted that the overall problem was at the stylus tip but he and the other Agoners just all disagree with my post and one of their posts told something like: " M.Fremer Atlas sampler has over 1.5K hours and he reported no single problem ".

Time latter the Atlas owner looks how the stylus tip not only was worn but broken and that cantilever stylus tip is second to none.

No matters what and what the cartridge manufacturers say and if we want to preserve in better condition our beloved LPs and we want to have a " steady " high quality level performance for any and I mean it: ANY cartridge we must to retip between 500-800 hours no matter what.

Many of us are not aware of the stylus " problems " because our home audio system has not a good overall resolution or our ears gone/goes " accustomed "  to the sound and maybe we have not a in deep evaluation proccess to check time to time the listening experience with our cartridges, a proccess that at least needs to have 10-12 recording tracks with different LPs that we know perfectly what we are listening even its click/pops kind of tone. With out this kind of evaluation proccess is almost imposible to evaluate not only the stylus level performance but nothing else. We need that knowlege level.

We can think that MF has that knowledge level but if you read his reviews he always is listening through the review different LPs almost never listening the same LPs with the same LP tracks ! " and he is a " professional reviewer ".

500-800 playing hours is the retip time, no matter what.

Of course this is my opinion only the ONE important is what  all of you think about.

Btw, thank's for your links very useful and leave no " land " to any dude or arguments against it because the research was made it by cartridge manufacturers true EXPERTS not audiophiles or music lovers like us.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R

Dear @rauliruegas, Thank you for your post. And the heads up about Ortofon research. I may inquire again with them. You have been there before, and so have I and as reported in my essay, so have others. Even after I posted a link to my article, which others tell me is well researched, folks assert that retipping at say 500± hours is "nonsense." That is the main reason why I say at some point in my article in reference to me, "People generally believe they know far more than they actually do, and as a consequence, they can be highly skeptical of new information." As Bill Walton is famous for saying, "You can’t teach someone what they don’t want to know." That noted, my recommendation is simple, at about 500 to 600 hours, have your stylus tip checked for wear. If the 500 hour marker is nonsense, the check will reveal that.

I have not done original research on stylus wear. I know that. I only report what Shure and JICO and Harold Weiler and many others actually learned though empirical research. If that is insufficient to get folks to at least check their stylus tips for critical wear, you can’t do more. Advanced tip shapes are designed to maximize the contact with a vinyl groove across the tip and groove. That is why they are so good at high frequency reproduction. And they exhibit distortion only at the point they are damaging record grooves.

But these shapes are still made of diamond. And diamond wears. Shape matters not on the rate of wear; it is VTF per unit area of tip exposure. A lot of that wear comes from grit embedded in the record groove that defies our ability to remove it. Some folks believe that dirt begins to abrade the diamond tip, creating in the process diamond dust. The additional of diamond dust is even more abrasive thereby accelerating tip wear. This is supposition on my part yet I have made an inquiry of someone who knows to see what the precise process is. However, I was told point blank by someone with many, many decades of direct observation that stylus tip shape makes little or not difference is stylus tip life.

Coming from me, I understand that is hearsay. I’m sorry. So that brings me around to the simple recommendation to have your tip examined at about 500 to 600 hours so that you can learn from yourself if it has critical wear. If that examination proves your tip is barely worn, you now have a strong reference point. But if you do not check it, and insist they last for 1,500 hour or more, well, they are your records. On the other hand, maybe on some systems, 500 hours is too soon, it is nonsense. Just check it.
Again, thank you for reaching out and I am glad you enjoyed the piece. It took me a lot longer to put together than I originally anticipated. But I did it to learn, and learn I did.

Some styli must be replaced not after 500hrs, but after 200-300 hrs max, it is all depends on the stylus profile (conical or elliptical dies fast). There is no universal rules for all stylus profiles. Diamonds are not alike, look here.

I have original user manual for ZYX Premium 4D cartridge in my hands right now. What i can read about Micro Ridge (0,07mm) stylus lifespan is 2000 hrs at 2gr. (contact radius 3 um x 60 um). Do you think the manufacturer cheating us claiming the life span is 2000 hrs with 2gr. tracking force ?

If every $5000 MC cartridge must be retipped every 500-800 hrs it is a nonsense to buy them at such high price, because the original manufacturer does not provide a retip, but provides only exchange to a new cartridge for 60% of the retail price.

If you can’t hear the difference between 500hrs used and brand new stylus on MM cartridge with advanced stylus profiles like MicroRidge (1500hrs life span at least) there is absolutely no need to exchange the stylus. You can also compare two samples of the same model of MC to make sure.

The best indicator is our records, if the story with worn styli is true (i mean some high-end diamonds) then all our records must be thrashed already after 500 hrs, but they are not, and some records are 40 years old already.

P.S. With a macro lens on my iPhone i can’t get closer to the stylus than this or that, easier with huge diamonds like replicant-100 or fineline