Michael Kellough said:
Corbin said
“I learned here to mount the guide rail such that it would lay with a slight skew so that when placed on the front support bracket it would have a bias to one side of the pin thus removing any slop.”
That is the key. Digest that and you’ll be a lot closer to knowing how to use the very usable MFT.
The mentioned slop is only part of the problem. Poor design. Registering pin should be made of plastic, just like on FT rail protractor. On the protractor even its width is adjustable.
The
biggest problem is that rail supports don't register well vertically. They allow side to side movement when the height is changed and can get clamped down in a skewed position. Again, just poor design. That's why so many people make their own contraptions or prefer to register from bench dogs to make square cuts.