Quote Originally Posted by derekcohen View Post
I shall be blunt - a 40 degree bevel angle is a recipe for premature dulling...
There may be more instances of premature dulling than just a 40° bevel...

We obviously all have different experiences. I have good success with 35 ~ 40° bevels when used in combination with closely set (~0.5 mm) cap iron and taking shallow cuts.

I quoted Paul Sellers because I think he's right in questioning the so-called "rules" around bevel angle, not because of his reputation. My own experience also showed that the results are good, even with hard Jarah or River Red Gum. I'm going to try it on Forest Red next when I have time to see if the sky will fall in.

I found that when the edge gets dull, the splitting of fibre becomes less pronounced but the severing of fibres still works - resulting in less curled shavings, but without obvious tear outs. The plane always maintains that crisp cut feeling when I push it through a piece of timber. With advances in sharpening, we are able to quickly re-sharpen the blade and continue again, and these wider bevel angles open up new possibilities.

By the way, I don't sharpen beyond 4000 grit. I sharpen my dull iron on a Tormek 1200 grit diamond wheel and then polish it on a 4000 grit Japanese wheel. It gives me a mirror bevel which cuts beautifully.