I've never had that happen…so this is more "thinking out loud" than anything. First I wonder if you really should have turned all of them, I suppose it's possible the old ones have just a slight amount of wear that the new ones don't (I see this as unlikely, but just a though). When I first got my Shelix, I had line runnning the length of the board. I removed every cutter, cleaned the saet, and re-torqued them in to the same spec (I think it was 45 in-lbs). That seemed to solve the problem…again, I see this as unlikely in your case….but just a though. Last, thinking through what caused that failure and could anything have happened to the balance of the inserts to cause the problem…just s though; and this may go back to rotating them all. Actually, that would have been a good idea anyway IMHO. Wish you luck and hope someone has some better ideas. Be sure to let us know if you find the solution.

 

Agree with Fred; clean out under all the cutters.

Sucks, i did that when i installed my Shelix cutterheads in my planer and jointer. I used brake cleaner and a soft brush from harbor freight (came in the little 3 pack, one black, one brass, one steel bristles)

 

I've had a couple of the inserts in my planer (735/Shelix) explode, too. The first one I attribute to overtorquing and the second to some embedded dirt. Carbide is brittle and doesn't take abuse well.

After the second fracture, I needed to rotate a number of inserts and experienced the same issue as the OP. Took of all the inserts, cleaned at each location with mineral spirits and a toothbrush, reinstalled. All was well.

The lesson I learned was that every time I need to rotate an insert, I also clean the insert and the mounting location well before reinstalling.

 

The portable planer heads with their small diameters only have a few rows of cutters and accurate torquing of those cutters is very important. When rotating or replacing them make sure you use an inch pounds torque wrench and not just the hand tool that comes with the head. Also as stated, make sure the seats are clean to avoid the cutters sitting at different heights which is what causes the scalloping.

Here is a link to the factory cutter installation instructions.

Byrd Cutter install Instructions