Bruce Sharp is a part-time
Carbatec staff member in our Melbourne store and a Manual Arts teacher.
He has devised this delightful project on making your own small bow saw.
Here is a little home-made bow saw. It really works. Its blades are cheap
and readily available. It costs very little. Even better than its function
is the fact that it looks good on the tool wall in the workshop.
Wooden bow saws or frame saws have enormous appeal for lovers of classic
woodworking tools. They still make a great addition to a modern workshop
and can be used for ripping, crosscutting or cutting curves. The traditional
shape comprises of two vertical arms and a cross beam that is mortised
into the arms. This beam provides the fulcrum around which the blade is
tensioned using the notion of a Spanish windlass. This is a lever that
is threaded through a piece of rope tied to each arm and twisted in order
to bring the two points closer together thereby adding tension to the
blade on the opposite side of the arms.
The timber in this kit comes from a renovation in South Yarra where a
Jarrah floor was being replaced and I was able to rescue a few of the
boards before they were thrown out. You will see that some of the pieces
still have nail holes in them. To make multiple kits I set up a little
mass production system. Sides for the saw were cut using a jig that incorporated
a clamping system, template and a flush trimming router bit. You can make
it as a one-off with no problems though.
It’s a great little holiday project for yourself or would make a terrific
Christmas present for a woodworking friend.
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Bruce outside his workshop. |
Band saws, scroll saws and jig saws all do an excellent
job of cutting curves in wood. Why would you make my bow saw project?
…because woodwork should be fun!
This little saw cuts wood, but its greatest function is that it reminds
us that our craft is fun. I believe that you should make it from a wood
that you enjoy, sand it to 400grit then rub it over with a nice tactile
wax. Cut something with it to reassure yourself of your cleverness then
hang it on your tool wall in homage to precursors.
I made it from scraps of recycled Jarrah then shared it with customers
on a sale day.
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I use a jig to make up my side pieces but they can be done individually
on a bandsaw. |
My drawing leaves out many details for I don’t want the
tyranny of millimetres to discourage creative explorations of existing
scraps. For instance, I wonder how small this project could go. Could
it use a pinned scroll saw blade? Could the frame be made from acrylic
pen blanks? We mustn’t stop exploring and sharing our creative urges.
Even if we don’t do it, someone else may take up the idea. Have fun.
Bruce Sharp
Materials you will need:
- Sides - 210mm x 25mm x 18mm
- Stretcher - 190mm x 25mm x 15m
- Toggle - 110mm x 20mm x 5mm
- String - 600mm
- Brads - 2 x 30mm
- bolts - 2 old ones
- 10mm coping Saw Blade
The bolts are designed to hold the pinned coping saw blade
in place.
Step 1.
Hacksaw the long cut into the bolt. (make sure you hold it firmly in a
vise)The angle cut can also be done with a hacksaw, although a Dremel
is good for this if you have one.
Step 2.
Cut the curves on the sides, you can use a rasp or a Microplane to smooth
out the bumps.
Step 3.
Clamp the sides together and drill a 16mm hole (see diagram for the exact
position )
Step 4.
Using a disc sander or a beltsander round off the ends of the stretcher
and pre-drill a small hole
in the sides for the brads to go into the stretcher.
Step 5.
Drill the hole through the sides for the bolts that hold the blade in
place.
Step 6.
Shape the toggle to whatever shape you like, this is used to tighten the
Spanish windlass.
Step 7.
Finish the timber with a couple of coats of oil, linseed or danish oil
is good. Then the bow saw can be assembled.
Step 8.
Hammer the brads through the sides
into the ends of the stretcher and tie the rope loosely around the top.
Fit the bolts through the holes and attach the blade. Tension the blade
by turning the toggle around the rope, when the blade is tight allow toggle
to rest against the stretcher.
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