some woods like birdseye maple or curly maply have multiple grain directions, and vertually impossable to determine which end to feed. When you get into glue ups with these types of grain multiples, it even further complicates the issues.
Rule of thumb I use is run each board through the planer a few times, slowly lowering the cutter head until it just touchs the wood. Run it through both ways. Eye the tear out, and mark the ends of the board feed and tail. Helps on glue ups as well.
Once the glue ups are ready for planing, do much the same thing. I seldom find myself lowering the cutter head more than 1/128th of an inch, or 1/8th turn on the TP1300 for anything. Always rotate and board so your planing both sides once a flat surface has been established.
When getting close to the finished size you desire, always run the board through twice before adjusting the cutter head. This will help eliminate tear out. The feeders will compress slightly, and even with 1/128th inch cut depth, you will be surprised what a 2nd pass will take off. And will give a smoother finish to sand when ready for finishing.
It's a true joy to experiment and gain knowledge of how to beat the wood to get the results you desire without frustration. Never an easy task, but a scrimmage I take to heart with a winning passion.
A true test of yourself on beating tear out is turning a solid core of birdseye maple into a finger grip handle! (I've yet to release the stock without using files and sandpaper, arrggg)
John E. Adams<br /><a href=\"http://www.woodys-workshop.com\" target=\"_blank\">www.woodys-workshop.com</a>