There are power planers out there specifically designed for surfboard shaping with on-the-fly adjustments for tapering foam(a huge help for shaping rocker, foil, and rails), special dust chutes and handles but any planer will do the job. Just make sure it's got 2 blades so it doesn't tear the foam. We sell an affordable entry level power planer that does a great job on both PU and EPS foam as well as stringers.