The Xacta Fence on my Jet Contractor saw has two set screws on the inside
face of the clamping mechanism which are used to adjust the fence so it's
parallel to the blade. By inside face, I mean the piece that fits betwen
the rail and the saw. To access them you have to take the fence off, or at
least lift the front section. I'm not sure what the standard fence has, but
would assume it's similar.