A couple months ago I decided I wanted to make a turning saw which is a larger version of a coping saw with a tensioned wood frame. Grammercy Tools from NY makes a modern one for $180 US. They also sell the blades for them, which are quite good quality, and they offer a plan and parts if you want to build your own. LV sells the blades and that's where I got mine. Probably the trickiest part are the pins that hold the blade. Like a coping saw they are split and have an angled groove to hold the blade. Grammercy sells a pair for about $40. I decided to try making my own.
I used a Dremel type tool with an abrasive disc to cut the slots and the angled groove for the pins on the blade. The pins are thicker than the blade is so I had to open the angled slot up wider for that. A hacksaw works for either job too. I decided the best way to attach the pins to handles was to thread the pins and the handles. One picture shows threading one of the handles with a standard metal tap. The plan calls for 1/4" pins so I tried using a piece of 1/4" steel rod for one and modified a bolt for the other. I'll stick to using rod next time. There was no advantage to using a bolt. I had to extend the threads anyway.
The pattern for the arms, stretcher, handles, and the toggle that twists the string to tension the blade are a free download from Grammercy. They print actual size on ledger sized paper ( 8.5 by 14 I think that is). There is a test scale on the drawing to make sure it's the right size. Grammercy makes their saw from hickory and I recently bought a piece so I did too. The handles and toggle I turned from Siberian elm. To shape the wood I cut the patterns out and glued them onto my blanks with fish glue. Grammercy uses braided fishing line for the tensioning string. I used some strong colorful cord I bought at LV.
A bow saw/turning saw is a bit superior to a coping saw, not only because it's twice as long but also the twisted string keeps the blade in tension whereas the coping saw relies on the spring it it's frame to keep the blade in tension.
Making a turning saw
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Cherryville Chuck
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Making a turning saw
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smitty10101
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some more info
I can explain it to you but I can't UNDERSTAND it for you!
Wait a moment, let me overthink it.!
Of course I talk to myself, -- sometimes I need expert advice.
Wait a moment, let me overthink it.!
Of course I talk to myself, -- sometimes I need expert advice.
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Cherryville Chuck
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Re: Making a turning saw
Looks like we are up and running again.
I watched the video he has of him making that saw before I tried making mine Smitty. I watched a couple others as well plus Paul Sellars making a frame saw which is the same thing but bigger. I threaded my handles and inset the nut like Rex did. Grammery's pins have grooves and a flat on one side and you epoxy them into the handles. I think threading the handles with the inset nut is a better idea, much more secure. Threading the handles also allows some adjustment between the blade and stretcher bar so that the arms are vertical when the blade is tight, not that they have to be. That just looks better.
The other main difference between the Grammercy design and Rex's is where the stretcher meets the arms. Rex slotted the ends of the stretcher to fit over the arms. Grammercy uses mortise and tenon joinery for theirs. Some frame saws I've seen cut a narrow slot in both sides and install a roughly 1/16" thick piece of metal and then put a single pin in the arm and stretcher so that each end can swivel a bit as the string or wire tightens. Grammercy, in the write up about the saw I'll link to, says that that type saw is common in Viet Nam and they don't bother with any type connection. They just depend of friction to hold it all together when the string is tightened. So there are a few options for that.
Rex uses a paddle to tighten the string. That's easy to make but it doesn't look very refined. You have to twist it sideways or push it up to clear the bar when you tighten the string. A tapered pin like Grammercy uses looks better and clears the bar with less effort but it takes more work to make.
Grammercy's plan is free. It's the pdf at the bottom of the last picture above. I guess they offer that so you'll buy parts from them. Here's a link to their write up on turning saws. https://toolsforworkingwood.com/store/item/GT-BOWSAW12
I watched the video he has of him making that saw before I tried making mine Smitty. I watched a couple others as well plus Paul Sellars making a frame saw which is the same thing but bigger. I threaded my handles and inset the nut like Rex did. Grammery's pins have grooves and a flat on one side and you epoxy them into the handles. I think threading the handles with the inset nut is a better idea, much more secure. Threading the handles also allows some adjustment between the blade and stretcher bar so that the arms are vertical when the blade is tight, not that they have to be. That just looks better.
The other main difference between the Grammercy design and Rex's is where the stretcher meets the arms. Rex slotted the ends of the stretcher to fit over the arms. Grammercy uses mortise and tenon joinery for theirs. Some frame saws I've seen cut a narrow slot in both sides and install a roughly 1/16" thick piece of metal and then put a single pin in the arm and stretcher so that each end can swivel a bit as the string or wire tightens. Grammercy, in the write up about the saw I'll link to, says that that type saw is common in Viet Nam and they don't bother with any type connection. They just depend of friction to hold it all together when the string is tightened. So there are a few options for that.
Rex uses a paddle to tighten the string. That's easy to make but it doesn't look very refined. You have to twist it sideways or push it up to clear the bar when you tighten the string. A tapered pin like Grammercy uses looks better and clears the bar with less effort but it takes more work to make.
Grammercy's plan is free. It's the pdf at the bottom of the last picture above. I guess they offer that so you'll buy parts from them. Here's a link to their write up on turning saws. https://toolsforworkingwood.com/store/item/GT-BOWSAW12