Bowsaws are available in various shapes and sizes, from 530mm (21”) to 900m (36”). A bowsaw is essentially a frame which pulls a disposable blade under tension.
The frames are made of steel tube, either circular or oval in cross section. Frames with plastic hand guards are recommended. Check the frame for burrs, and ensure tension levers are secure. The holes for rivets and studs should be clear of mud, wood and other debris.
Tensioning on most saws is by lever operation. Oil the pivot of the lever occasionally to ensure smooth operation and secure fastening. Some saws have no levers, but are sprung to tension the blade. Depending on age and type of saw, the blade is fixed either by a tongue, a rivet or nut and bolt. A tongue fixing is preferable, as rivets, nuts and bolts are easily lost. If the tongue breaks, rather than throw the saw away, a hole can be drilled for a small nut and bolt to secure the blade. Any saw that cannot hold a blade under tension should be discarded, although it may be possible to restore the tension by holding the saw in a vice and bending the ends apart slightly. Frames keep their tension longer if they are stored with the tension released.
Blades usually lose their set before becoming blunt, by being trapped in the felling cuts of trees. This makes them bind in future cuts, giving the impression that they must be blunt. The blade can be given a new set by gripping it in the vice up to the base of the teeth, and then tweaking each tooth in turn to the correct side, using a pair of fencing pliers. Grip the tooth below the hardened tip or it will break off. Although not a very accurate method, it is effective and gives the blade a new lease of life. Blades are not worth resharpening.
When not in use, the saw blade should be protected with a plastic guard.
