I knew you would try your best to come on with an answer Jim and thanks for the information and a look at your sawing technique.
Timbeal also thanks for coming on board and your remarks on the centifugal versus the centripetal forces. I had to look it up in the dictionary because I wasn't familiar with the term myself, but then again I am only an old farm boy with a one room school house education.
I am sorry Jim I mistakenly thought you were familiar with the workings of a Mulley Mill, to this end and for the sake of others that drop by I will quickly review the basic workings of such a mill.
I believe that everyone knows now that the Mulley Mills were basically driven by water, used a vertcal 6 foot blade, and in some cases 7 foot blades, these blades were stiff enough to withstand the upper thrust of a pitman revolving under the floor level, or in the area adjacent to the water barrel.
The saw frame was on the second floor and was usually mounted on wooden v shaped hardwood slides imbedded into the soft pine beams of the saw frame and slid back and forth passing by the blade on other v shaped hardwood blocks imbedded in the floor timbers.
I had mentioned that there were no modern methods used to roll the timbers on the saw frame, just cant hooks and pointed bars.
Once loaded on the saw frame the log is positioned in front of the blade in such a way that the best use of the log can be realized. The log is held in position for the cut by pounding in heavy cast iron dogs on each end of the log.
What I had eluded to was once a sufficient flat surface was cut on one face of the log, (usually 2 cuts). the log was rolled 1\4 turn on this face and then lined up for the second series of cuts.
Now the first 2 boards had both edges round and these boards were laid aside. The next set of boards all have one flat side, and if you cut right across the log all the boards would have one flat side and some of the centre boards would be quite wide and have some nice outside material in them. In a maximum centre cuts you could obtain a few 25 or 26 inch boards from a large pine log
This was the fastest way of cutting up a log with a Mulley saw, but edging the boards was tricky because there were no centre supports in a mulley saw frame only end supports, only one being moveable to accomodate different length of logs.
We normally squared our timbers getting as much good lumber from around the heart and as Jim mentioned as you neared the centre during the final cuts at times the final piece would be a little out of square or varied in dimension from end to end.
We used to vie with one another to see who could saw out the truest lumber and finish up with the centre cut true end to end, not an easy feat on these old saw frames, but quite possible if you took care in set up.
These blades had 2 inch teeth at about 2.25" spacings, and the teeth were bent slightly alternating to create a cerf.
The blade was also slightly out of perpendicular so that on the up stroke the teeth would lift away from the face of the cut, and gave the log enough room to move ahead before the blade descended for the next cut
I hope this helps explain the workings of a mulley mill, they could be very temperamental and each cut had to be monitored to be able to compensate its wanderings on each succeding cut.