Buck Saw Patents

I started looking through old buck-saw patents, trying to figure out the concept behind the ubiquitous double-bow design of the Fulton buck saws sold through the Sears catalogs during a period spanning more than the first quarter of the 20th century.  I discovered that the design was patented by Daniel & Edwin Moore, of Brooklyn, NY, in 1860.  (US Patent #94,500)

Illustration from 1860 Buck Saw Patent #94,500 and Fulton Clipper from 1915 Sears & Roebuck Catalog

From what I gather, the idea is that tightening the rod at the top will cause the upper bow to bend downward, pressing on the lower bow, forcing it to straighten out, thus tightening the saw blade at the bottom. The inventors didn't really explain why this is superior to using a single straight stretcher, but the popularity of this design shows that it must have either worked better or wowed the manufacturers and users by its elegance. Intuitively, it does make sense that spreading out the compression & expansion forces would allow for a lighter and/or stiffer frame.

The early Sears catalogs (1895-1902) sold both this "braced frame" style (54-cents) and a cheaper 35-cent "plain frame" saw. Later catalogs, through at least 1929, sold only the braced frame models. Most years there were 3 models offered. The more expensive ones were painted red. As far as I can tell, these all had 30-inch blades.

Sears & Roebuck 1895 "Braced Frame" Buck Saw (54-cents) & "Plain Frame" Buck Saw (35-cents)

At some point, at least some of these saws began to be manufactured with two rivets holding the bowed stretcher together, reflecting the Christopher Eisenhardt patent of 1888 (#394,477).

Christopher Eisenhardt 1888 patent #394,477 and Fulton Special buck saw sold by Sears & Roebuck for 64 cents in 1913

The oldest US buck saw patent that I could find was given to James Haynes of Hollis, Maine in 1859. He replaced the upper tightening mechanism (usually a turnbuckle, threaded rod, or twisted cord) with a solid bar, and put a ratcheted tightening device at the end of the blade opposite the handle. This mechanism somewhat resembles the tightener on the handle end of a modern metal bow saw. Apart from the criticism that this exposes the tightener to abuse by sawyers who, like me, use their tool as a walking stick, it seems that this would put excessive stress on the upper bar, which appears in the patent's illustration to be a wooden stretcher with pinned tenons. I have trouble picturing these joints holding up to the outward force that would be generated by tightening the blade and putting the saw to work. His 1861 improvement, which expanded the center stretcher, got rid of the first criticism, but would still have put a lot of outward pressure on the top bar.

Haynes 1883 reissue of Patent #25,015 & his 1861 Patent #31,045

A couple of other early patents were given in 1860 to William H. Livingston of New York City. These designs (US Patents #30,073 & 30,076) used various hardware to stiffen the basic buck saw.

Patent Illustrations for buck saw improvements by William H. Livingston, 1860.

A variation on the Moore brothers' double-bow design was patented ten years later, in 1870, by William Hankin, Sr.  (No Google, I did not mean Hank Williams, Jr.), who apparently worked for the Harvey W. Peace, Ltd. tool company in Brooklyn, NY.  His design used a single double-forked cross piece in place of the two bent bows.

Wm. Hankin Sr's US Patent #104,847 with Harvey W. Peace Co. Ltd. "Elliptic" Saw Frame
"The strongest frame ever made.
The above engraving represents my Elliptic Forked Saw Frame, which commends itself to the trade for its simplicity of construction.
The Forked Brace being all in one piece, without any centre bolt, secures for the Frame great strength and durability.
NOTICE.
We are informed certain parties are imitating our justly celebrated ELLIPTIC SAW FRAMES,
placing them on the market as NO. 116 and PETITE.
We claim these are infringements of our patent, and will protect it to the fullest extent.
HARVEY W. PEACE CO. (LIMITED) BROOKLYN, N.Y."

A point that should probably have been made earlier in a discussion on buck saw design is that in most cases, the stretcher (the center support between the tightening rod and the blade) should have loose unglued tenons or be otherwise held so that the verticals (i.e. the handle and the other vertical support) can pivot freely upon it. A glued tenon would be apt to break from the angular change from tightening the saw. In any case, the blade and tightening rod will hold it together as long as they are in place and fairly tight. An advantage of allowing the saw to fall apart when loosened is that it can be stored and transported more easily. In fact, the most common use of this type of buck saw today is probably the portable, self-storing version made of lightweight piping and advertised for backpacking.

My point here is that I have doubts about the Hankin/Peace design. From the illustrations, it does not look like there would be much independent flexing between the upper and lower branches of the stretcher's forks. This would cause the verticals to pivot on the upper branches and pull away from the lower ones. This would stress the upper branches, and depending on the grain orientation of the wood, would be likely to cause it to crack. Indeed, I don't see this type advertised widely as antiques, so I assume they were failures.