A step drill bit includes a shaft for coupling the step drill bit to a drill and a drill bit portion coaxially coupled to the shaft. The drill bit portion has a plurality of step portions. The drill bit portion may further include three cutting edges wherein the cutting edges are spaced around the drill bit in substantially equal arc angles. The step drill bit further includes surface treatment having a first coating formed of first material and a second coating formed of a second material that is applied over the first coating. The step drill bit further includes a replaceable drill bit tip.