Dual Cam Setup

JBarca wrote:
After thinking about this, the friction load cannot be linear with the DC once the WD keeps moving. One of the underlying claims to fame which makes this anti sway control so effective is the WD bar increases in tension as the WD rides up the cam. The increased tension increases the friction holding action.

I've seen that claim to fame -- but I've never seen any substantiation of it.

In this post, I attempted to address the increase in WD bar load for a sway angle of 5 degrees.
My analysis gave the folloing:
For a large sway angle of, say, 5 degrees, a cam will move about 0.5" longitudinally and, due to the slope of the bar, will lift the bar about 0.25". The added upward force on the bar will be equal to 0.25" times the spring constant. For an 800# bar with a base load of 1000#, the force will increase by 0.25"x200#/inch = 50#. The upward force will increase from 1000# to about 1050#. For a 1200# bar with a base load of 1000#, the force will increase from 1000# to about 1075#.

IMO, the "claim to fame" for the Dual Cam is the fact that the cam/bar friction force is much greater when the TT is trying to swing away from centered than it is when the TT is trying to swing toward centered.

Now relearning that... :S what assumptions did you use to create the 2,170# breakaway force? Is that the initial breakaway friction force pulling the WD bar up hill? Meaning only at one point in time as the WD bar 1st starts to slip on the cam. As once the bar starts sliding, the friction lowers slightly as it is sliding friction vrs static however the WD force is believed to be increasing riding up the cam which will increase the friction force nce again.

What did you use for the coefficient of friction? 0.5 to 0.7?

As stated on my diagram, the friction force is assumed equal to 0.6 times the normal force. That means the assumed coefficient of friction is 0.6. Since the slip speed between bar and cam is quite small, there probably is very little difference between the static coefficient of friction and the dynamic coefficient.
Again, if we're talking about sway conditions as opposed to sharp turns, there is very little relative movement between bar and cam and very little change in WD bar load.

Ron