Tom Sontag - St. Louis
>Your method may be dead on right as far as I know, but except for a fully employed engineer using college level math daily, it is of little use to a woodworker. Just because mathematics is capable of expressing a problem does not mean it is the best or fastest way to solve it. I am not even sure what the number you solve for gives us toward a final solution to flattening a sole.

How about this method? Apply tool at hand (imperfect cast iron surface) to problem at hand (unflat sole) with ~80 grit abrasive in between after tuning other already-mentioned more important plane tuning aspects. When significant results are noted, attempt to use the plane on wood. Note results and adapt further efforts accordingly.