I am probably the only person in the last 20 years to add a top saw to a tractor/farm circular mill. The saw is a B.H.Payne number 2 1/2 , 24 inch, 8 gauge, with 18 bits... a 2" mandrel runs thru a 3"x4"x1/4inch wall rectangular tubing with 3/8 inch 3"x3" angle iron welded to the sides. Flange bearings are bolted to each end of the tubing. The mandrel assembly is supported by 9" channel iron securely fastened to the husk frame. Diagonal bracing has been added to the C iron and husk. Four B vee belts run from the jack shaft, which is powered by a JD 520. This turns the top saw backwards from the head saw. All the metal and sheaves, except the saw mandrel, came from the scrap pile.
