How to change a bow saw blade

How is the blade attached?

A bow saw has a removable blade mounted in a metal frame. Like all frame saws, the blade must be stretched taut in order to cut efficiently.

The blade is held in place by two metal pins at either end of the frame which hook onto two corresponding holes on either end of the bow saw’s blade.

Removing the blade 

Step 1 - Turn wingnut anti-clockwise

Locate the wingnut and turn it in an anti-clockwise direction.

The wingnut controls the movement of a metal bar underneath the handle, which holds one end of the blade. Turning the wingnut anti-clockwise moves this bar forward, so the blade is no longer stretched in the frame. 

Step 2 - Unhook blade 

Once enough tension is released, you can remove the blade by unhooking it from the pins.

Unhook the side closest to the handle first, then turn the saw around, and unhook the other end of the blade

Installing the blade

Step 1 - Loosen wingnut

Ensure the wing nut is loosened before hooking the blade back onto the pins.

Hook the side furthest from the handle first, then turn the saw around and hook the side closest to the handle.

Step 2 - Turn wingnut clockwise

When the blade is in place, turn the wingnut in a clockwise direction.

This moves the metal bar back towards the handle, pulling the blade taut in the frame.

How tight should the blade be?

If the blade is too loose, it will move about on the pins and could even fall off. A blade with too much movement will bend in the material and it will be hard to control the saw when working. However, stretch the blade too much and it could snap, potentially causing an injury.

As a general rule, you should tighten the blade enough so that it does not move about on the pins, but can still flex very slightly in the middle.