"Dr. Deb" wrote:

The spreader bar is connected to the uprights of the frame with
a "NON-GLUED" mortise and tenon joint. The whole thing is held
together
with the tensioning string/rope/wire.

A question:

As a kid, my dad described a one man saw with a frame and a 24"-30"
long blade as a "Buck Saw", used primarily used with a cross buck to
cut up brush from fallen trees.

Had a turn buckle arrangement inside the frame to tension the blade.

Is that the same as what you are describing as a "bowsaw"?

Lew