Hello everyone!
My latest project has been making a sort of smaller version of the large continental style turning bow saws -- not turning saws, but general purpose saws that can turn to allow for ripping and such. The total length of the saw is about 23", with the blade being about 18" long.
Inspired by Chinese woodworking videos someone posted, I'm going with a very simple design utilizing bolts for the pins, and I'm experimenting with using a threaded rod and wingnuts for tension (I think I may prefer string and toggle after all - it looks much nicer. I've just had some issue with the strings snapping). I'm calling this my "hardware store" saw. There's a certain beauty in simplicity, even when it's kind of ugly!
Anyway, I've got the basic frame of the saw built, and am using a bandsaw blade at the moment, but I wanted to try making my own blade from scratch.
My ideal was something thin, along the lines of a Japanese saw blade, with around 12 or 14tpi, rip-cut, and wider than the 1/2" bandsaw blades I've been using to allow for straighter cuts. I'm not a fan of universal teeth, which is why I opted against the turbo-cut blades that are popular.
So, I'm not sure if I've got the right stuff here, but I bought:
Spring Tempered 1074/1075 Spring Steel, .018" thick, 1" wide. RC hardness around 43, if I recall correctly - I may be slightly off.
It's a got a bluish coating or residue -- I assumed the color is from the tempering process, as that's what it looks like, but it does seem to want to "spread around" when I wipe it with my thumb.
So, at this point, I admit to having very little knowledge of metal and metalworking! But hey, this is how one learns, right?
I wasn't sure what thickness to go with. I did want a thin blade, as it will be tensioned and I figured I could get away with something thin to reduce the effort when sawing. 0.018" is a little thinner than I expected, and I wonder if I shouldn't have gone for .020 or .025 though; I'm a bit worried about being able to tension it properly. But we'll see! As far as the steel is concerned, though, do I appear to have the right stuff?
What preparation should be done to the stock before I start filing teeth into it? The edges are kind of rounded, so perhaps I should square up the edge that will form the face of the teeth with a file and polish the blue residue off the faces of the steel (a fine grit auto sandpaper, maybe?)? As for doing the teeth, my plan was to build a little jig out of wood with stepdowns at the interval that I want my teeth, and use that as a guide for my file. File the teeth, and then just set them with a screw driver, as I've been doing.
So... Is my plan of action sound thus far, or?
Reply With Quote