The 3 teeth rulke isn’t something written in stone ; more like a
generalization about optimum performance, not universally true in all
situations. One situation I have all the time is sawing 1/16" thick
tool steel with a #1 blade, which works out very close to exactly 3
teeh for the thickness of steel, but it’s not necessarily the fastest
blade. I can saw faster with a #2 blade but it’s physically more
demanding, and since using a bigger blade also requires increasing
the sawing angle on pancake dies - which is where I do almost all my
sawing these days- I choose not to do it. It’s mostly because of the
added difficulty.
I also use the same #1 blades on thinner steel, which violates the 3
teeth rule (less than 3 teeth), but I do choose to do that often,
precisely because I can saw faster with a #1 than with a #0 or #1/0,
and pushing the #1 is within my comfort zone, and in spite of the
fact that it increases the angle. It gets a little complicated
explaining it all in detail, but basically I use as big of a blade as
I can most of the time, because bigger blades saw faster, until I
start to run into the wall of difficulty. The wall is ok to launch
one’s self at sometimes, but I do have to pace myself and be careful
of repetitive stress issues.
Anyone who’s tried sawing 1/16" tool steel with a 4/0 blade will
understand my desire to do that as infrequently as possible, and only
when required to do so in order to obtain sharp detail. In general, I
choose blade size determined first by degree of detail required, and
as stated, I go with the biggest blade I can get away with, up to #1
and sometimes #2.
Lube is a funny thing ; I use beeswax when I use anything, because it
causes less steel dust to stick to the die plate. Sawing dies,
keeping the blade cool is not the only reason to use lube ; lube can
help blades from binding when the steel shifts and tries to pinch the
blade. It also functions like it does in an engine to some degree; it
prevents metal on metal wear, which is definitely an issue sawing
tool steel. I said a few days ago that wax can also cause blades to
veer off course, which may sound weird, but it does happen, though
I’m not sure why. It’s more than a little annoying to have a perfect
line going, put some wax on, and have to fight to keep it going, or
have your butt kicked by a stupid blade (^;. Sawing normally, with
the sawing hand doing the turning, I don’t recall ever noticing this
(and I was exceptionally good with a saw long before I took up die
sawing), but with dies, the sawing hand doesn’t do the turning, so
the difference is noted in adjustments that have to be made in
turning the die plate as you saw around your design. There’s no
question that wax helps cutting tool steel. I wouldn’t use a tap or
threading die without oil or tap lube, so it isn’t 100% about keeping
the tool cool in all situations.
D. Shelton