A turning saw dates back many centuries. It is basically a frame for a thin, narrow blade with a thong or rope to tension it, twisted by a stick. It is primarily used for cutting curves in wood, for instance cutting carvings or spoon blanks. It is, in fact, a poor man's bandsaw and that, in fact, is where the blade comes from. At yard sales you can pick up bandsaw blades for a dollar. You don't care if they fit your saw or not. The saw above was made a year or more ago. It works very well but it is too big (40 cm blade) for my small stuff, and in winter, as we all know, we do small stuff here at Chalupy acres. So I need a smaller turning saw. I still had a lot of bandsaw blade left (just as well, as it turns out).The first job is to make the uprights and the stretcher.
Then you saw the thing above in half, drill holes in the uprights and attach the blade. This last task is the most difficult part of the whole operation.
First, you saw a slot in the knobs, right on the diameter, all the way down into the handle. Then you drill a very small hole in the handle at right angles to the slot (cross-drilling it is called). Through this hole you will put a pin (brad, in my case) which will go through a corresponding hole in the blade. So you have to drill a teensy hole in the blade.
So you measure carefully and break off your bandsaw blade to the right length. (Run a three-corner file over it to score it, put it in a vise, snap it.). If at this point you tried to drill it you would either break the bit or have it skitter off the blade. The blade is hard. So you have to anneal the blade. Sorry I didn't get pictures of this -- too busy! You take your trusty propane torch and heat 2 cm of the blade ends red hot. Let it cool. Voila, annealed. Now you can drill it. Problem: this particular blade is about 3mm wide. My original brads, 1.7mm. Extreme precision is called for. I didn't do it, and paid the price. The hole in the blade was too big, broke under tension. Tomorrow I will remake the blade (sigh) and this time I will use a very small pin, 1.4mm, which I found in my odds and ends, and my Veritas optical center-punch. But oh well, live and learn. Getting the pin through the hole in the blade requires patience. Bad language is futile. Play it again, Sam, as Bogie did not say in Casablanca.
Here is the collection of turning saws:
I got some use out of Mr Middle before the blade broke. It will be a very useful tool for roughing out carvings, spoons and other curvy stuff.
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