Hi. I just purchased a circa-1994 Powermatic Model 15 planer that needs a basic tune up. This is my first planer. It didn't come with the knife-setting jig, so I've decided to 3D-print my own. I took some rough measurements today and modeled the cutterhead in CAD. The cutterhead itself is 2.875" in diameter, and I read in several places that having the knives protrude 1/16" beyond the cutterhead is good. 1/16" protrusion makes the overall cutterhead diameter 3", which is what I modeled.
Looking at my model, which probably isn't super-accurate, but isn't bad either, it looks like the tips of the knives protrude beyond the gibs just .009" (red arrow distance in the attached detail pic). The blue dot distance in the pic is .074", so just a bit over 1/16".
Does this look right? I'm concerned that .009" isn't "enough tip," and that I'll be constantly adjusting the blades to keep enough edge past the cutterhead. On the other hand, I've read a few posts saying the "less tip" the better.
I can certainly move the blades out (limited by the amount of lateral clearance to the chipbreaker), but I'm not sure this is the right thing to do, and it changes the cutting angle (although I don't know how sensitive these machines are to changes like that).
Thoughts? Also, thoughts on the knife-setting jig shown in the overall pic?
Thanks!