At the risk of tooting my own horn, I did a deep dive on this issue- stylus life- in helping Mike Bodell publish an article on the subject entitled "The Finish Line for Your Phono Cartridge." Mike, who is a geologist by training, found that his cartridge was beginning to exhibit signs of wear at far fewer hours than those claimed by the manufacturer, which led him to explore the subject extensively, starting with Harold Weiler’s seminal paper from 1954. Mike updated Weiler’s work based on what he was able to learn, including discussions with manufacturers and retippers and a search of the literature. He also had help from Ray Parkhurst, who not only did the photomacrographs for the article, but in a thread on the Hoffman forum, did a real time test of wear using a lower stylus force than I am accustomed to-- interestingly, Ray’s real life tests showed very little wear at 1,000 hours, when Mike’s expectation based on the data should have revealed otherwise. (I think part of it may be stylus pressure- remember when the ultra light stylus force designs were all the rage? Maybe they had something there). I guess the main take away is that the multiple thousand hours claimed by some manufacturers is probably the outside limit.
One user on the Hoffman forum said he had been running a cartridge for years without any noticeable wear. But, once he finally convinced himself to have it inspected, it turned out that it was worn (I think it was a London Decca) and had it redone by the manufacturer. The user reported that he had not realized how much gradual degradation occurs over time that you don’t really notice. (I find the same with tubes).
The other take away for me was to keep track using a tally counter. It isn’t a big deal to click the counter each time you play a side- this is "rough" approximation, not scientifically exact, but gives you some idea of how many hours of play are on the stylus. You might find the Bodell article or the Hoffman thread of interest if you curious about the subject. (I like working on these projects with specialist authors and always learn something).
