How do tell when my stylus is too much worn?

I keep my cartridges very clean. They last a lot longer than they probably should when reading about what manufacturers/reviewers say cartridge life is. In my experience the suspension starts to go bad. When that happens things start to get muddy. 

I always use a test record when I install a new cartridge, and use it as a reference to check the cartridge.

Of course I should remove the cartridge and view under a microscope but un mounting and remounting is a perilous business that I would like to avoid.

Looks like you will void visual examining of stylus and only limit yourself to finding stylus problems only by ear which is somewhat inefficient.
Very often you may find degraded performance of inner tracks including sibilance. Also in diamond stylus less likely diamond tip is affected, but more likely stylus mount and cantilever which is visible under jewelers loupe 

Dear @rrm: 800 hours? looks not excessive. Now, manufacturer can tell us that stylus tip can goes over 1K hours or even 2K hours.

Now, the stylus tip degradation can be faster when LP's are not well cleaned and when the stylus tip is used not well cleaned or both. These accelerates the stylus tip damage.

My take with any stylus tip is to re-tip after or near 500 hours. This gives me ( someway. ) certainty that my LPs surface can't be damaged for it and that thank's that the stylus tip has no more hours its performance will be really near as when 200-300 hours with almost no demerit in the quality performance of what I'm listening.

For me 800 hours says it's time to re-tip but this is me.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.

Raul

All cartridge maunufacturers must love you!

500 hours of use then discard is total BS!

Beogram turntables with moving coil are still around since 80's and sounding good. Most of decks with lost styluses had been mishandled by owner. Others perform like champions. Unfortunately for some reasons cartridges aren't made anymore for them, or worth the fortune. I hoarded at least several Beograms with needles and checked their styluses and noticed little to no gunk and no loss of suspension integrity that is including tip and cantilever mounts. 
To be sure I carefully applied CRC spray on each and every one of the vintage cartridges. The playback is exceptionally clean for outer and inner tracks. 
Diamond tip can serve forever, but suspension and cantilever is what wears out. In case of beograms with lightest arms, the suspension is never too stressed. 

Raul,
500 hours is certainly safe but may be a little extreme. I'm sure it depends on the manufacturer. I read somewhere that dynavectors are only supposed to be good for about 800 hours. I have an old karet with 3 times that on it & it still looks & sounds fine. Anyway, this is straight out of my current cartridge manual:
The normally lifetime of a Clearaudio HD Diamond is by careful treatment and correctly adjustment up to 8000 hours!
Notice the words "up to". However it also has a boron cantilever & I keep my records & cartridge clean so I'm hoping I'm set for a while. :-)  

Not to muddy the waters but doesn't Van den Hul suggest 3,000 hours for his cartridges?

Dear @don_c55 / @czarivey / @boxer12: The issue is " deeper " than manufacturer specs or what we think and experienced about.

Many years ago Ortofon published what they found out on the stylus tip wear. They make several tests and declared that the diamond tip starts to shows ( under microscophic. ) tiny signs of wear just after 250 hours when LP are well cleaned as the stylus tip. They did it ( if I remember ) with 3 different stylus tip shapes where the line contact " suffers " a little higher signs of wear.

In the past with vintage cartridges no manufacturer that I can remember spoke on 2K hours or more even not 1K hours and many of them spoke on those 500 hours and the stylus tip diamond ( as material ) was not different on the newer cartridge designs.

Now, we have think on the turtouse road and very high friction/forces generated between each LP groove and the really tiny tiny stylus tip surface that are in contact.
It’s true that diamond is at the top of the mohs scale: 10 for harness but even this is not " immune " to wear.

In the other side and at microscopic levels that’s where everything is happening during playback: a " tiny " scracht in the LP grooves it shows it for the stylud tip a if that " deformation " been the Everest mountain and needs to " figth " against it. The LP surface have macroscopic and microscopic scratches and other kind of " anomalies " that for the stylus tip is a serious obstacule where sometimes the stylus tip looks one of those anomalies as if was a big stone of 1 ton.

Over that LP surface is full of dust and it does not matters how well we cleaned the LP. Exist microscopic dust that we can't see it. As a fact it’s in the room enviroment and is attracted my static or just gravity inside the grooves. This kind of dust degrade the stylus tip life and certainly the grooves integrity.

Ok, we can’t hear or be aware of that kind of damage and what we listen is fine, we don’t listen any kind of " aberration " during the cartridge tracking job.
This is influenced by what @rrm/OP posted:

""" I suspect that the change would be so gradual that it might be hard to tell, as the ear slowly accomodates. """

and maybe because the room/audio system has not the level of resolution for we can be aware of.

If our target is to have and stay with the very high quality levels in our room/audio system then my advise is not wait over those 800 hours to re-tip the cartridge.
I think that 500-600 hours is what we have to take in count.

As I posted that is me but as always with any audio subject is up to you.

Regards and enjoy the MUSIC NOT DISORTIONS,
R.

Records are sometimes much more valuable than bloody needle, and if that's the priority one should disregard figures of thousands of hours and replace earlier. 500-600 hours is of course very conservative but why not? I would stay under 1000 hours, anyway.

It is also debatable whether slightly rounded edges on a slightly worn fancy diamond, result in more audible record wear than say one with a simple conical tip. Of course the fancy diamond will sound better, but is there less record wear?

I have old records played many times on cheap old MM cartridges from the early 70’s that sound "mint" with expensive properly setup MC cartridges of today.

Records can survive more abuse than you think. Also your system resolution comes into the equation..

I feel the best solution is have two interchangeable arm tubes (like VPI and other brands) which contain a new and older cartridges for audible comparison.

If you can not hear a difference, you do not need a retip, or new cartridge.

I do that.

@rauliruegas , publishing sometimes do not match real facts.

Raul,
Do you listen to more vinyl than digital? Just curious how many times a year you re-tip? 

another one of signs of warn stylus is it's not erect anymore and may fall down almost to the chassis under normal tracking weight.

Dear @don_c55 : "  I have old records played many times on cheap old MM cartridges from the early 70’s that sound "mint" with expensive properly setup MC cartridges of today. "

in those old times cartridge stylus tip was conical that let the deep information recorded in the grooves " untouchable " , so are as " new " and with line contact shapes that information comes alive for the very first time. Yes, LP surface is resistent to the stylus tip very hard friction. Now, that for whatever reasons we are not aware either the stylus tip wear levels or LP surface damages does not means is happening each time we use that cartridge and any LP.
My take is to try stay " always " in a safe umbral.

Btw, @boxer12, I listen both sourcves but a little more on analog. I own 100+ MM/MC cartridges and normally I don't stick with one of them but more rotating . I still own cartridges that I never tested yet.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.

Raul

The MM cartridges that I referred to from the 70's were Shure M97 and were elliptical not conical!

It is more about the size of the diamond tip than shape.

Dear @don_c55 : Yes,but M97 came with different stylus shape and inside the shape different dimension. They came: conical, two different ellipthical and hiperellipthical too.

Anyway, microridge or replicant or VDH2 goes deeper in the grooves and this helps in the quelity of listen levels. Of course that with today stylus shape the cartridge parameters for the set up has no " margin " to error if we want top quality performance levels.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.

I just got the CBS STR-100 test record which has some tests purported to reveal wear and excessive VTF. I haven't pulled out a worn stylus to see if it works yet, though.