I need to make a 2 Axis gantry system, that will not carry a cutting tool but a 3”x3” dia disc magnet that will have 800lbs of pull.

This 2 axis gantry system will need to move under a table and housed in a giant box, Idealy id love a 5ft x 5ft square area or larger of travel. The magnet will move a single ball bearing on the top of the table.

So I was curious what you guys can recommend in ways of a setup. I have some experience using CNC systems since ive been using a Tormach PCNC, Shopbot 120x96 and a torchmate for 2 years now here at the school.