I built my own band mill, I used V belt pulleys, and hung a V belt on them for tires,
(my understanding that is what woodmizer does), the belt hangs loose but is as small as can be put on the pulley, (it is self cleaning), and made some ball bearing guides using bearing from press wheel from a JD planter, and there bushing,
(most likely if doing it again I would use the tires as I think one can tension the blade via air pressure, instead of making a tighteners for the wheels),
all manual no hydraulics, the track is heavy angle iron, and it rides on 4 V belt pulleys, with bushings in the bore,
I use the same blades that fit the basic woodmizer band saw,
I made a mechanical belt clutch, If I was rebuilding I would put a electric clutch on it like on a lawn tractor has on the deck, or use a large electric motor on it if electricity was available and not using as a portable unit,