Hi Don and others:

The early water powered Sash saw mills predated the muley mills, which was a later refinement of vertical blade sawing technology.

Muley blades were manufactured from saw steel that was thick enough (about 5\16" by 12" in width) that the requirement for a sash was done away with.

I believe you will find out that the sash saw mill's blade and associated guides had to have the same lead on the upper end of the sawing apparatus as the muley mill's blade and associated guides needed to accomodate the forward motion of the log on the up stroke of the sawing motion.

Please get back to us with an answer from the sawyers that you are associated with I am interested in what they might have to say on the subject.

NH