Introduction: Make a Bow Saw (aka Frame, Turning)
Making a bow saw is easy with a few basic woodworking tools and skills - why not have a go!
Two videos are available. One with full details plus a shot of the plans, the other just showing the build
Free plans are available to download from my website: http://www.womadeod.co.uk/p/blog-page_9.html
You'll need some hardwood - I've used European beech (fagus sylvatica) and Dark Red Meranti (shorea spp.),
some non-elastic cord, a couple of steel pins, and a band saw blade (good way to use up broken ones).
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Step 1: Arm Mortises
Layout the mortises as per the plans you downloaded ( http://www.womadeod.co.uk/p/blog-page_9.html ), or to your own design
Chop them out - I've made them through mortises, which I feel maximises the frame rigidity
Doing this before shaping the arms makes it easier to clamp whilst chopping!
Step 2: Stretcher Tenons
Layout the tenons on the ends of the stretcher
Saw the tenon shoulders and cheeks
Fit the tenon thickness to the mortise at each end
Step 3: Mate Mortise & Tenon Joints With a Curve (Optional)
This optional step makes for a strong hinge connection for transferring tension to the blade
Mark identical shallow curves at the shoulders of the tenons, and entrance face of the mortises, using a pair of compasses
Pare the curves with sharp chisels
Saw the tenons to width, making them narrower at the ends so that they can rotate in the joint
Step 4: Shape the Arms and Stretcher
As an absolute minimum, you need to shape a notch near to the top of the arms, to prevent the tension cord from sliding off
You also need to bore the holes through the width of the lower arms. I also cut a slot here, which allows for a sprung grip on the saw's blade handles
Ideally shape a comfortable grip handle too, and why not include a little decoration as well
A coping saw, rasps, and files will handle all the basic shaping
Step 5: Make Blade Handles
Turn blade handles on a lathe
Alternatively, glue a slim dowel through a thick dowel to make a very simple but functional blade handle
Slit the slim section, to take the blade
Step 6: Attach a Blade
Install the blade handles in the assembled frame, and drill blade attachment holes
Cut a length of blade the width of the frame (internal size)
Mark for, and drill attachment holes in the blade
Install the blade and secure with steel pins
Step 7: Tension the Blade
Tie a loop of cord around the upper arms, sitting in the notches
Twist cord around and insert the tension toggle (simply planed up from a length of hardwood)
Use the toggle to continue twisting the cord until the correct tension is achieved, and allow it to lock against the stretcher
Step 8: Finished!
You're ready to saw!
To protect your tool, why not give it a coat of boiled linseed oil.
Thanks for reading my instructable. If you build a frame saw, using these instructions and plans, please do let me know, and post a photo if you can