IH= 950 lb, 30x12 table travel. Lathemaster= 730 lb, 21 1/4x 7 1/2 travels.
220 lbs of cast iron difference, and a bigger work envelope. I suspect the IH has heavier main castings, as the table size shouldn't account for all of the 220 lb weight difference.
Yup, just had a look and the IH specifies ribbed column and base.