USNR Yates A20 / A26

Chip marks are caused by chips recirculating back under the cutterhead. Check chip extraction suction, chip breaker clearance, and outfeed roll pressure to eliminate the problem.

Dimension drift between setups is usually caused by feed roll wear, thermal expansion, or incorrect size roll settings. Measure finished lumber with a caliper after each setup and adjust the size roll to compensate.

Knife chatter produces washboard surfaces on planed lumber. Check knife clamping torque, knife projection uniformity, and feed roll pressure before replacing knives.