One thing that can be overlooked setting up a new frame or set of brakes is the contact surface on the Brake tab. Many times from the factory we will find a brake that is "just off a bit". The usual spacing adustments don't seem to be enough. This leads to one part of the disc pad dragging or not centering properly at all. Typically this is do to paint covering the mount contact point.
One of Mountain Road Cycles favorite tools is the Park DT-1 Disc Brake Mountain Facing tool. The mechanic inserts this into the front or rear axle, adjust the contact point of the cutting teeth, and remove just enough paint and frame to have a precise flat surface to mount the brake. Here is the whole process
Of coarse we do this on all custom builds and anytime it's needed. You know the saying---The right tools for the right job!
