This assembly was designed by Westbury in 1941 for use on his 1831 IC Locomotive and detailed again for the Wallaby engine.
We believe that this will be an interesting accessory for other engines as well; allowing a simple means of decoupling the engine from its load at low engine speed. The kit comes with construction notes 2 gunmetal castings, cut bar for a flywheel and a suitable ball race. The 4 tension springs are not included. You will need to experiment in order to achieve the best results.
Westbury suggests engagement should begin at 800rpm and states that there is a "wide transition between first engagement and full torque".