Planer accessory tool for an oscillating power tool

An accessory for an oscillating power tool, comprising:

• a mounting portion including a plurality of openings configured to receive a plurality of protrusions of a tool drive structure to mate with a tool holder of the oscillating power tool, the mounting portion defining a first plane;
• a substantially planar, rectangular guide portion extending forwardly of the mounting portion to a leading edge and having a flat lower guide surface defining a guide plane;
• a transition region that is interposed between the mounting portion and the guide portion, the transition region extending downwardly from the mounting portion to position the guide portion such that the guide plane is parallel to and offset below the first plane;
• and
• a cantilever arm having a cutting edge and extending downwardly from the guide portion to position the cutting edge a predetermined depth below the guide surface and forwardly toward the leading edge, the cutting edge including a plurality of cutting teeth extending forwardly from the cutting edge,
• wherein the guide portion includes an opening that extends through the guide portion,
• wherein the cantilever arm extends forwardly and downwardly beneath the opening, and
• wherein the cutting edge of the cantilever arm is arranged substantially parallel to and spaced apart from the guide surface.