There are at least a handful of frame saw designs floating around the web. Most of them don’t make much sense to me from an engineering perspective. I want to share what I think is a good design, but first: what is the application for a frame saw in 21st century?
- In a minimal tool kit. Keep rip, crosscut, and metal-cutting blades in a bundle with the frame
- On a budget- frame saw blades are affordable and easy to sharpen
- Scroll cutting without a bandsaw
- Cutting metal by hand
- Hot-wire foam cutter?
The bushcraft community has produced a decent amount of frame saw content. The bulk of a frame saw frame is a pain in the woods though. They’re really not usable for pruning in my experience. For bucking logs, maybe it’d be more practical.
Here’s the general idea of the design:
Without the long mortise and brace piece on the left, the saw becomes forced out of shape in use (think a parallelogram). The saddle joint on the right is kept as shallow as practical to keep beam strength in the vertical members.
Here is a saw I made of this design:
The cotter pin blade-holding method allows the saw to rip sections deeper than the throat of the saw, by rotating the blade. The spreader is made of cedar (light) and the arms made of douglas fir (strong). The whole thing is overbuilt as usual; the next one I make will be skinnier and lighter.
Here’s a fleshed-out version of the CAD model. Ideally the spreader would be tubular. We’re green woodworking though- the next best thing is a lightweight wood that’s close to cylindrical.
Like the rest of us that use hand tools to sustain ourselves, I wish some of the resources that went towards making fighter jets and race cars were diverted to making human-powered tech. Things like these saws, carts, hand trucks, hoes, pry bars, etc. The next best thing? Make it yourself.
I made the cart from EMT and hoop house scraps. The hay fork I made based off a picture of the fork I wanted–it was unavailable then and still is a year later. The scythe handle is made from a willow pole my neighbor gave me and the aluminum ring welded from more scraps. The clover was used as mulch on the garden we grow food in.