Dull Spiral Cutters Indication

[Mike Chalmers]

I have had my 8" Jointer with spiral cutterhead for about a year. Have put, roughly, 2400 bd ft through it, mostly pine. I see no indication of any tear out or rough finish, which is what I am looking for as my warning to rotate the cutters. My planer cutters will have been used for a year come Christmas.
Does that sound right, or should I be looking for other signs to indicate the edges have dulled?

[glenn bradley]

If the surface is acceptable and operation seems normal I would carry on. the indication for me was greater resistance in feeding and definite tracks left from the dull cutter "beating" the wood fibers. My jointer went about 18 months before my first rotation, my planer did about the same. I am conscious of using the full width of the machines. I do this by moving the fence in the case of the jointer or by feeding at an angle or in different positions for the planer.

[Peter Aeschliman]

Agreed. If you don't have tear out and you're not having to push too hard to feed the stock, you're probably fine.

[Mike Chalmers]

Thanks both for confirming my thoughts.

I love my spiral cutter heads!

[Andrew Hughes]

I say take out one insert and look at the edge with your magnifier.And decide if it looks sharp compared to a fresh edge.

[Andrew J. Coholic]

I have had my 8" Jointer with spiral cutterhead for about a year. Have put, roughly, 2400 bd ft through it, mostly pine. I see no indication of any tear out or rough finish, which is what I am looking for as my warning to rotate the cutters. My planer cutters will have been used for a year come Christmas.
Does that sound right, or should I be looking for other signs to indicate the edges have dulled?




Mike, I have a 16" jointer, and 20" planer - both with 30mm long carbide inserts in the head (six rows). I process at least somewhere in the teens (approx 15 thousand BFM) in terms of board feet of hardwood yearly. I flip or replace my inserts every spring, whether they need it or not. But I know based on my using the machines and also inspecting the cutters, that they could go much further.

[Jim Andrew]

Pine has a lot of pitch in it, and I would guess your cutters are dirty, not dull. I use Grizzlys bit and blade cleaner in a spray can, along with a tooth brush. I spray the head down with wd 40 after cleaning.