Bowmen of Skelmersdale

Static and Dynamic Properties

Objects take time to start moving, and while they are being pushed about fast, they don’t behave in quite the same way as when stationary. Think about what happens if you push a rubber ball slowly. It seems to move immediately at the speed of your

hand. But if it is struck hard, say with a baseball bat, the ball flattens a bit against the bat, so although the whole thing is very quick, for a very short while after contact, the bat is moving faster than the ball.

Something similar happens when a bow fitted with flexible stabilisers or TFC’s is shot. It takes time for the stabiliser weight to be affected, as the flexible stabiliser takes up the initial bow movement. So the full effect of the stabiliser weight is not felt

immediately by the bow which, for a very short time, behaves almost as if unstabilised. That is one reason for the development of the TFC, or ‘torque flight compensator’, and also part of the reasoning behind the recent move back to shorter, more rigid stabiliser rods - to make sure the weight affects the shot.

Exercise: Set up your bow without stabilisers. Without letting the bow rotate, move the bow smoothly back and forth (along the arrow line rather than sideways). Then fit all your stabilisers and repeat the experiment. Was the bow as easy to move?

What bow behaviour needs controlling?

Bow  movement

Timing - When is movement important?

Time and Motion

Controlling bow displacement

Weight, Mass and Inertia

Static and Dynamic properties

The misnamed TFC

Controlling bow balance

Centre of Gravity

Finding the centre of gravity

Changing the balance using weight

Weights and Distances

Rods, weights and risers

Controlling bow vibration

Causes of Bow Vibration

Reducing Vibration - Damping

Bow Resonance

Tuned damping - more on TFC’s