At the Las Vegas show I saw the Shelix planer head. I have a 15" Delta planer, and I just had the knives sharpened but it still wants to tear-out on maple. Any help or suggestions would be appreciated.
From contributor A:
From what I read on these forums, multiple overlapping knife type cutter heads leave ridges, but the helical/shear type cut will lessen tear out. A lot of woods, including maple, will tear out in the planer if you feed to the knives against the grain in the board. I have a straight knife planer and I deal with the issue of tear out by first flattening one face of the stock on the jointer.
I look at the edge of each board and make an estimate as to grain direction. If I hear the grain tearing, I reverse the board for the next pass. After I know which way each board machines the best, I have simple methods to keep track of it. Then when I plane them to thickness, I run the boards according to what I learned about their grain direction on the jointer.
In the event that a board is straight and flat enough to go directly to the planer without the need to face joint, I estimate the grain direction and take a light pass through the planer. If the grain tears out, I reverse the direction of feed for that face. This method is difficult if you use S2S (13/16") material and need to net 3/4" thickness. I almost always inventory 15/16" hit or miss as my 1" material. 15/16" material leaves lots of room to plane out any tear out if a board gets planed against the grain at first.