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Thread: Making my own bow-saw blade

  1. #1
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    Making my own bow-saw blade

    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?
    Last edited by Luke Dupont; 06-04-2016 at 9:34 AM.

  2. #2
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    I don't know about steel type so I'll let that to others.

    When I completely redo all the teeths of a saw I prepare, with my computer, a very simple layout with a whole bunch of vertical lines side by side. I print that and, if it's not exactly the teeth spacing that I want, I just zoom it with the copy machine. This paper get folded over the edge of the saw and each line show me where I need to start filing.

    You're doing a project that I have in mind for quite a while. I'll be following your progress.

  3. #3
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    1095 or 1075

    I've been playing around with spring steel to make a kerfing saw blade, specially shaped scrapers, and chair devils. I went with 1095 spring temper steel from McMaster Carr at 53Rc. That seems to be what most of the saw makers tend to use. The 1075 you have will be easier to work, but dull a bit faster. For what you are doing either will work.

  4. #4
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    It would have been better if you had chosen 1095. It has more wear resistance. But your steel will do,except it is VERY THIN,and may well distort under the tension needed to saw with it. .025" would be a more ideal thickness. If it isn't too expensive for you,i'd recommend using .025" before you go to the considerable trouble if hand filing the teeth,setting them,and then having a disappointment later on.
    Last edited by george wilson; 06-04-2016 at 12:34 PM.

  5. #5
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    Quote Originally Posted by Mark Fisher View Post
    I've been playing around with spring steel to make a kerfing saw blade, specially shaped scrapers, and chair devils. I went with 1095 spring temper steel from McMaster Carr at 53Rc. That seems to be what most of the saw makers tend to use. The 1075 you have will be easier to work, but dull a bit faster. For what you are doing either will work.
    Rc53 is a little hard for a sawplate IMO. Standard triangular taper files would be somewhat marginal for cutting that, though very hard files like Valtitans would work well.
    Last edited by Patrick Chase; 06-04-2016 at 5:58 PM.

  6. #6
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    It seems like most of the modern saw makers are using 1095, and everyone seems to agree that it is harder (that is, harder-wearing and harder to file) than older manufactured saw plates. So 1075 might be closer to the carbon content of good earlier saws, and could work just fine, though it might need sharpening more often than the 1095. Much depends on the tempering, of course.

    I measured the plate thickness on two older bow saws which I have. A Peugeot Freres rip saw with a blade about 2 feet long and 1 1/2 inches wide is 0.28 thick; an older German or Scandinavian turning saw with a blade about 2 feet long and 1/2 inch wide is 0.26 thick. The plate you have does seem on the thin side, but might be worth a try since you have it - at least it will give you some practice filing even teeth. I should think you want to cut quite fine teeth with a bade that thin.

  7. #7
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    I always used 1095 from Precision Steel Warehouse. Good American made steel. And,the 1095 was always 52 RC.. I never tested any that was 53,and had a first class hardness tester. A Versitron.

    So,I would agree that 53 is a bit hard,but 52 is what ours was,and it is also a little hard on files. But,it stays sharp much longer than old saws that were softer. Probably more like the 1075 @ 43RC..
    Last edited by george wilson; 06-04-2016 at 6:06 PM.

  8. #8
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    Quote Originally Posted by John Vernier View Post
    It seems like most of the modern saw makers are using 1095, and everyone seems to agree that it is harder (that is, harder-wearing and harder to file) than older manufactured saw plates. So 1075 might be closer to the carbon content of good earlier saws, and could work just fine, though it might need sharpening more often than the 1095. Much depends on the tempering, of course.

    I measured the plate thickness on two older bow saws which I have. A Peugeot Freres rip saw with a blade about 2 feet long and 1 1/2 inches wide is 0.28 thick; an older German or Scandinavian turning saw with a blade about 2 feet long and 1/2 inch wide is 0.26 thick. The plate you have does seem on the thin side, but might be worth a try since you have it - at least it will give you some practice filing even teeth. I should think you want to cut quite fine teeth with a bade that thin.
    Sawplate hardness is determined by both the alloy and the temper. 1095 is Rc65 or so as hardened, but can be tempered all the way down to Rc30. The corresponding range for 1074 is Rc59 to Rc25 IIRC.

    EDIT: See George's post above.

  9. #9
    I prefer the slightly softer plates. The harder ones are so much harder to file that I put it off longer and so end up using a slightly dull saw longer. With the softer ones, I just stop and spend 10 minutes bringing back the edges and I'm back to work with a sharp saw.

    Just my $.02

  10. #10
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    Quote Originally Posted by Normand Leblanc View Post
    I don't know about steel type so I'll let that to others.

    When I completely redo all the teeths of a saw I prepare, with my computer, a very simple layout with a whole bunch of vertical lines side by side. I print that and, if it's not exactly the teeth spacing that I want, I just zoom it with the copy machine. This paper get folded over the edge of the saw and each line show me where I need to start filing.

    You're doing a project that I have in mind for quite a while. I'll be following your progress.
    Very inventive! I hadn't thought of printing them out.
    I think I will go for the step-downs-in-a-wooden-block method though, because I'm figuring that will give me a definitive, physical method. Paul sellers has a neat video on this in which he gets the cut started with a fine-toothed hacksaw that he's modified. I might try that, I'm thinking.

    Will do on the updates! Like-wise if you pursue the project yourself at some point!


    Quote Originally Posted by Mark Fisher View Post
    I've been playing around with spring steel to make a kerfing saw blade, specially shaped scrapers, and chair devils. I went with 1095 spring temper steel from McMaster Carr at 53Rc. That seems to be what most of the saw makers tend to use. The 1075 you have will be easier to work, but dull a bit faster. For what you are doing either will work.
    Oh hey! I guess I could play with making scrapers, too. Though, I'd imagine what I have may be a tad soft for scrapers. For a saw, I don't mind it being a bit soft - I figured it would be better to learn on softer steel first, as long as it's sufficiently hard for my purposes.


    Quote Originally Posted by george wilson View Post
    It would have been better if you had chosen 1095. It has more wear resistance. But your steel will do,except it is VERY THIN,and may well distort under the tension needed to saw with it. .025" would be a more ideal thickness. If it isn't too expensive for you,i'd recommend using .025" before you go to the considerable trouble if hand filing the teeth,setting them,and then having a disappointment later on.
    Hey george! I agree; the .018" strip was thinner than I expected. I think I'll order some .025", but considering that what I have is both on the softer and thinner side, I think I'll go ahead and give it a shot so that I have some practice filing the teeth if nothing else. The steel will take about a week to get here, so I'll have the time - all I've got to lose is the effort. I'll definitely go thicker with my next subsequent blades, though.

    Thanks for the advice, by the way! I do highly value and appreciate your knowledge and experience!


    Quote Originally Posted by Jim Davis View Post
    I prefer the slightly softer plates. The harder ones are so much harder to file that I put it off longer and so end up using a slightly dull saw longer. With the softer ones, I just stop and spend 10 minutes bringing back the edges and I'm back to work with a sharp saw.

    Just my $.02
    That's kind of my thoughts on sharpening, too. Granted, I think the few resharpenable saws I own have been on the harder side, and of a more recent make. They're definitely not as easy to file as some of the antique saws I've seen people filing in videos. So, we'll see how it works! I can always get some 1095 if I find it too soft for my liking. I have a hunch that I'll prefer softer as well though. Better to learn on, at any rate!
    Last edited by Luke Dupont; 06-05-2016 at 12:01 AM.

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