More on Saws
Paul in NJ
>I enjoyed the 'Saw Making Questions' thread this past week and I thought it might
be interesting to measure the thickness of my saws and how they are tapered. These
saws are from the same period, roughly 1896-1917. This in IMO, and others will disagree,
is when Disston made his best saws. The handles were shaped nice and the consistency of
the steel, hardening, tempering, and finishing was excellent. The 26" #7 was from the
next period and looking at the handle it is starting to get more 'blocky'.
The measurements were made with a one inch micrometer and are in mils (1/1000 inch).
Due to the small throat of my micrometer I could only take measurements at the edges
of the blades. I started an 1-1/2" from the toe and measured every three inches. This
is a small sample of saws, my saws that had smooth blades, so take this for what it
is worth.
------------------------------------------------
24" Panel Saws (xcut)
........toe-------------heel
#7---33 35 33 33 32 32 31--Tooth Line....9 POINT
........29 27 27 28 28 30 32--Back
#12--30 31 32 38 38 38 37--Tooth Line...10 POINT
........18 18 21 24 25 28 29--Back
#16--34 35 36 36 36 35 34--Tooth Line....8 POINT
........23 24 26 27 29 31 32--Back
-------------------------------------------------
26" Hand Saws (xcut)
........toe----------------heel
#7---37 39 39 39 39 40 40 39--Tooth Line....8 POINT
........26 34 30 32 34 36 36 36--Back
#8---34 34 35 35 35 35 35 34--Tooth Line....9 POINT
........21 22 26 27 29 31 33 34 --Back
#12--37 37 38 38 38 38 38 38--Tooth Line...11 POINT
........25 27 27 28 30 31 34 35--Back
----------------------------------------------------
26" Rip Saws
........toe----------------heel
#12--36 37 38 39 39 39 38 38--Tooth Line....5 POINT
........23 25 27 28 31 33 34 37--Back
#16--34 37 38 39 39 39 39 39--Tooth Line....6 POINT
........26 28 30 31 33 35 37 37--Back
I will let you draw your own conclusions!
I am curious of the effect that ultimate hardness has on a saw. It would seem
a harder saw would be stiffer and go longer before sharpening. Modern spring
steel (from MSC) is hardened to 48R. I recall Disston hardened his saws to 50-52R.
Would 2-4 points Rockwell make a difference? I know Disston's earlier saws
sometimes hard spots or inconsistent hardening-tempering. In my limited filing
experience, later saws (1940's?) are not as hard which is one of the reasons I like
the saws from the 1880's - 1920's. If you haven't figured it out, I love my Disston
saws. But I still hope to build a proper tenon saw!
Paul Dzioba