I've been using the same planer knives for several years now, and they're still functioning. Although I do notice some glittery chips in the surface finish, which I think might be related to the grain direction rather than the blades themselves. I've put a lot of jatoba through them and now I'm working on a maple project, so they're really getting a workout. Changing the blades is such a hassle that I've put it off. I'm curious if there's anything specific you all watch for that indicates it's time to swap out the blades.
2 Answers
I have a Shelix head on my planer, and I usually just rotate the blades 90 degrees about once a year. Then, after that, I replace all the teeth the following year. It works pretty well for me!
For me, the signal to change blades is when my planer starts struggling to feed the boards properly. If the blades are dull, they can really screw with the rollers' performance.

How often do you use your planer?