Couldn’t help but notice scissor jack for spare tire is about same size as router on sled. The jack itself seems far too heavy and clunky, but was wondering if that sort of triangular force could help give a solid push into material 
ultimatly you are limited to the force of gravity (modified by the angle of the
frame), so you don’t need anywhere near the force of a jack. You also would have
the problem that a given amount of rotation will result in a different amount of
movement of the Z axis.
I don’t see the value of doing this over the simple linear movement with a screw
drive.
David Lang