Western or Eastern traditions ?
The Western technique is described in any good furniture book that
talks about the development of veneering in the 18th century. Although
resawing for timber was a skilled trade, the real experts were those
who resawed extra-thin boards (1/8" and 1/16") for veneers.
None (or little) of this was pit-sawing. That was the rough end of the
trade, sawing deals for housebuilding. The accurate resawing was
generally done with the board raised on large trestles or a fixed
framework - they needed light and visibility. It was done by paired
teams who always worked together (often for decades) and may have
travelled around the country as a working team. It's usual to think of
the guy on top (the tillerman) as being the brains of the outfit and
the guy underneath as little more than cheap muscle. For
cabinetry-grade resawing though, this is a disservice to the
The saws were frame saws, not bow saws. They had a wooden frame on both
sides of the timber and were often screw-tensioned, not string
tensioned. Blades were much deeper than bow saw blades (partly because
suitable steel was still poor before 1759). The design of the upper
tiller is distinctive between saws optimised for power or accuracy.
Water-powered framesaws are a very early innovation (medieval!) but
didn't dominate the whole trade until late into the 18th century. There
was a lot of regional variation as to the rate of adoption of machinery
- England was still leading America at this point.
In the Eastern tradition, it's generally a one-man task. "Timberyard"
resawing was done with short squat blades and short squat sawyers the
size of a small tree - these guys are sometimes said to have been the
founders of sumo. They were famously strong (which in those days meant
they were simply well fed). Again an outdoor trestle would have been
used to support the timber when resawing as boards. There's a famous
woodblock (Hokusai?) showing sawyers at work on such a frame.
Fine resawing was done by the final carpenter, not a specialist. Saws
were more like a ryoba or fine-toothed anahiki and had long rod
handles. The timber was supported on
low horses and the sawyer worked above it (often holding it down with
their bare toes, which I've never been too happy about doing!).
Typically for fine work only a few strokes would be taken, then the
beam turned over and sawn from the other side for a few strokes.