Andrew, I love the simplicity of your spring. Ingenious! I guess too that if the fork tyne gets in the way it is a very easy matter to just squeeze the spring open and shift its position on the knob. The amount of leverage you get from such a long spoke would be staggering!
Doug, great machining there to tap the threads. The spokes then just squeeze onto the knob to hold it in place? Yes, the amount of shake that a large diameter wheel provides is bugger all as the amount of effort to move it is so small. I barely need to touch the wheel I've made to achieve sufficient grip to move the focus. Shaking has been greatly reduced due to the focusing process.
My old C8 on its wedge really suffers from vibrations - heck, it shakes when a heavy car rattles past my place on the crappie concrete road in front of my house. The joint lines between the slabs have shifted over the years, and produce a strong 'thunk, thunk' as the wheels crash over the joints. Trucks and buses are even worse. This little mod at least gives some relief to the vibration sources. I had asked for some help with ideas on how to reduce the effects of the external vibrations in the General Chat forum, and I've applied some of these to great effect. Thank you if you had replied to my question there. I've had less agro with your help,