I'm planning a 5-axis gantry router approx 3m x 2m x 1.3m primarily for foam cutting and I'm currently carrying out structural analysis on the frame design to optimise weight/stiffness.

The cutting forces for foam are obviously quite low however I'm also interested in the potential to cut sheet materials such as MDF, plywood, acrylic etc

Not being an mech engineer, can anyone help with rules of thumb or equations that will alow me to calculate cutting forces for these materials from given cutter dimensions, travel/cutting rates etc?

Thanks