Bowmen of Skelmersdale

Tuned Damping

more on TFC’s

The continuous adjustment on TFC tension allows a very wide range of tuning to suit different needs. Tightening the unit leads to a higher frequency and vice versa.

Since a TFC is an effective damping device, that means a TFC/stabiliser

combination can be set to achieve the most effective damping for a wide range of frequencies.

Exercise 1: Fit a single short rod and TFC in either top or bottom limb mounts.

Slacken the TFC as far as possible. Tap the upper limb of the bow smartly, so that the limbs vibrate, and note how quickly they come to rest. By degrees (eg a turn at a time, tighten the TFC and repeat the procedure. What happens? If you observe a reduction in the oscillation time, continue tightening the TFC, and note what happens.

Exercise 2: Set the TFC to achieve the best damping. Add or remove weight (remove a cap weight or add a middle weight, for example).

Test the damping again.

What happens?

The short table below shows what sort of TFC tension will be needed to control different effects.

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