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View Full Version : Made another saw + blade (Chinese style bow saw)



Luke Dupont
02-17-2022, 7:58 AM
I've been in need of a few panel saws. The problem is, good western panel saws are expensive to ship to Japan, and take up a lot of space, which I don't have.

Solution? Well, how about a frame saw and a variety of blades for it? I made one of these in the past -- a much cruder one -- and liked it a lot.

Here's its reincarnation!

The handles are Walnut (which I'm now in love with), and the stretcher is Japanese cypress.

This is a Chinese style bowsaw -- a very simple and easy to make, but practical design. You can of course find European saws made in exactly the same way, however.

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In use, it is typically held at a 45 degree angle, with four fingers above and the pinky below the bolt which holds the blade.

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This is awkward at first, but the more I practice with this grip, the more I like it and find it easy to control. Just requires new muscle memory.

The blade is made from a tempered piece of 0.5mm spring steel, 20mm (3/4") in width (3/4" to 1" is typical of Chinese bow saws, even those used for fine woodworking). Took me the longest time to figure out what this is called in Japanese (焼き入りリボン / yakiiri ribon / "tempered ribbon" or literally "baked ribbon" for anyone who might stumble upon this thread wondering the same thing) so I could track it down, but it's apparently super common in hardware stores and home centers here. No idea what people use it for normally, but it makes great saw blades, and if my insane difficulty drilling the mounting holes into it is any indication, is definitely pretty hard despite the blue spring temper. If anyone knows how the hell I can drill this stuff without annealing it, I'd love to know, because none of my drill bits or improvised methods did very well.

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I marked the teeth by just marking out 1 inch (or close to, I'm using millimeters) intervals along the blade, and then subdividing those, and then subdividing them again and again into 10 teeth each, for a 10TPI blade. Be careful that you realize that you're marking out gullies, so you'll have one extra gully (11 gullies for 10 teeth) per inch. I just used a piece of masking tape and a pen to make this easy.

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I just filed the teeth out, one by one -- no using a hacksaw or anything. I recommend using a hacksaw or dremel to get down to depth though, because I wound up wearing out an expensive saw file by the time I was done.

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I set the teeth as one would normally do, but I'd caution you to use the absolute least set you can with such a narrow blade. I over-set mine and had to squeeze it out between the jaws of a vice and two sheets of aluminium.

There's not much to say about making the frame. I kept mine light. A little weight helps the saw in the cut, but with such a large frame, you want to keep it light and slender, especially if you don't have much experience with frame saws. A heavy saw is a huge burden on both your skill and your tendons, and being as my wrist tendons are not very strong, a light frame it is for me. This is why I chose to use a mortise and tenon for a narrow stretcher, and chose light woods (walnut is fairly light for its hardness, and Japanese cypress is definitely light).

The other point, is that you want the bolts to fit very tightly. You should not be able to rotate them with your fingers. I have to use either a pair of pliers, or a screwdriver inserted into the slot for the blade (the slot extends past the end of the blade, so I can still insert a flathead in and adjust the angle with the blade in). If the bolts become loose and turn too freely, the blade will rotate freely in the cut even under tension -- tension alone is not sufficient to lock the blade in my experience, even if you use metal threaded rods for tension. A string and toggle is actually easier and less hassle IMO. Less likely to damage the frame, too.

The difficult thing is finding a drill bit that is just a hair tinier than the bolt. Most bolts are slightly undersized, I think. My bolts are 8mm, but neither an 8mm nor 7.5mm bit worked for me. The 8mm hole was too lose, and the 7.5mm hole was too small. Fortunately, I happen to have an 8mm gimlet that for whatever reason, always produces a perfect, tight fit, so that's what I used. I can't really offer any help finding such a perfectly sized bit though. I'm curious if anyone else can offer suggestions. I'm just lucky to have a gimlet that works. Anyway, point is: you need that bolt to be very tight fitting!

I used wire rather than nails or tiny bolts to hold the blade in, as it's secure but not as fiddly and easy to lose as tiny bolts/screws.

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Luke Dupont
02-17-2022, 8:03 AM
All in all, I highly recommend making one of these.

You can substitute bandsaw blades of various TPI for coarse work such as ripping, or narrow bandsaw blades (1/4" works well) for turning. And you can of course make or buy wider blades than the 3/4" one that I made, if that's what you prefer.

I'll likely make some more blades in various TPI, and maybe even a farmer, peg toothed crosscut blade for bucking wood when I go bushcrafting (though simpler frames are usually used on such saws).

This is a great all around solution, and really flexible saw that saves space. The only thing is I think I may want to make a second frame so that I can have two different blades handy...
It's okay. They look great hanging on the wall!

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Oh yeah, and my new bench is now stained with embedded metal filing particles... As I knew would happen.

steven c newman
02-17-2022, 9:38 AM
In a video series from China along while back (Traditional Chinese Woodworking, GE HONG) he used what he called Watch Spring for the blades. Also, every third tooth, he did not set, but left as a raker tooth.

IF I counted correctly from watching his videos...he had almost 50 different versions hanging in his small shop. He also kept his left index finger alongside the cuts, as he was sawing, as a guide.

Set was made using a notch in the side of an old chisel.....something like Left, right, skip, left, right, skip......

Frame saw I built, following his video, Uses an 18" Butcher's Meat saw blade...9ppi.

Luke Dupont
02-17-2022, 9:44 AM
In a video series from China along while back (Traditional Chinese Woodworking, GE HONG) he used what he called Watch Spring for the blades. Also, every third tooth, he did not set, but left as a raker tooth.

IF I counted correctly from watching his videos...he had almost 50 different versions hanging in his small shop. He also kept his left index finger alongside the cuts, as he was sawing, as a guide.

Set was made using a notch in the side of an old chisel.....something like Left, right, skip, left, right, skip......

Frame saw I built, following his video, Uses an 18" Butcher's Meat saw blade...9ppi.

Yeah, that's why I posted a thread recently asking about raker teeth! I set all of my teeth on this one, but maybe the next blade I make, I'll try doing it his way just to see.

I tried searching for watch springs but no luck. I'm pretty sure it is the same material as what I found locally though.

I like the saw you built! I've not found a butcher's meat saw blade before but will certainly keep my eyes open for such things that could work.

steven c newman
02-17-2022, 9:53 AM
The blade he used came in a coil...already had teeth formed...He unrolled what he thought he would need. cut that. I think he used a drill press and a bit of oil.

Videos were in Mandarin...there are cc versions out there. He also had videos about making 3 planes....I did 2 of them..still have the "Jack"..
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Jack Dover
02-17-2022, 10:36 AM
Good job, a very neat looking tool!


If anyone knows how the hell I can drill this stuff without annealing it, I'd love to know, because none of my drill bits or improvised methods did very well.

There are diamond drills, but I'm not sure what's the smallest diameter they're available in. You could also temper only the ends, just wrap the blade in a wet rag exposing an inch or two, then heat with a blowtorch. You won't be using these inches anyway, I wouldn't even bother putting teeth there. Once you do it it will drill or punch easily.

Louis Lampe
02-18-2022, 10:09 AM
RE drilling/annealing:
Sounds like you need a 5/16¨ carbide drill bit, but that is $33 USD at McMasterCarr. Another solution that is often suggested but I have not tried is to first chuck up a common nail (with head removed) and use the friction from the nail to anneal just that exact spot then your drill bit has soft metal to work on.

Richard Hutchings
02-18-2022, 11:12 AM
RE drilling/annealing:
Sounds like you need a 5/16¨ carbide drill bit, but that is $33 USD at McMasterCarr. Another solution that is often suggested but I have not tried is to first chuck up a common nail (with head removed) and use the friction from the nail to anneal just that exact spot then your drill bit has soft metal to work on.

Now that's a cool idea, if I can just remember it when I need it. :-)

Monte Milanuk
02-18-2022, 3:02 PM
Looks great Luke! 👍

steven c newman
02-18-2022, 5:43 PM
In use, today,
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making shelves for the Tool Cabinets..
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Cuts a bit fast, though...
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I needed to tighten the blade up a bit...otherwise, wasn't too bad...

Luke Dupont
02-18-2022, 7:31 PM
In use, today,
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making shelves for the Tool Cabinets..
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Cuts a bit fast, though...
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I needed to tighten the blade up a bit...otherwise, wasn't too bad...

Nice to see yours is getting some use too!