SMT fence drags across table. why?

[vanzman]

and more importantly, how do I fix it?

[gmack5]

First, be sure that the SMT is down tight and square to the Rails. If the Left side of the SMT is UP just a little bit, it will allow the Miter Fence to drag on the Main Table.

If you're sure everything is down and square and it still rubs, then add a piece of slippery tape under each of the 4 corners on the SMT (About 1/32" thick or less).

Usually, folks complain that the SMT is too high, but you may be the exception.