We see below, the new paddle limbs in all their glory.



The careful fit-up between the convex impact block and the bronze hardstop is a deliberate strategy aimed at  putting  the maximum level of control over the limb tips through out the entire firing cycle.  If I cannot adjust the limb tips to within  +/-  1/4″  from being  equidistant  from the center of the bolt groove,  the machine will never live up to all its accuracy potential.   By reducing the thickness of one of the bronze hardstops, it will be possible to make the limb that shows the least distance from the CBG (center of bolt groove) match the limb that shows the greater distance from CBG.   Performing this adjustment will insure that the bowstring is picked up by the catch at its relative exact center.  Also, it is important that the bowstring zips along the top of the bolt groove with out much downward pressure.  Friction is the enemy of speed.  This is best controlled by having a design that keeps the limb tips at the chosen altitude.  With the design chosen here, the interaction of the convex impact block and the concave bronze hardstop, creates a fulcrum that helps control and maintain the vertical disposition of the limb tips.   Our experience to date shows that the massive clamping grip from the torsion spring,  is  more than sufficient to prevent vertical slippage in the limb position.  Adding this fulcrum should make the whole dynamic of limb movement much more precise. Very important stuff, if your goal is accuracy.

I am getting that sensation again.  The one where I feel we are building to the moonshot, getting  this thing ready to launch.  Details, details……. everywhere I look, details.   A new backstop has been completed today.  Tomorrow I will make up half a dozen bolts.  After that, all we need is a new bowstring and it will be time to see how the new paddle limbs perform on the range.  If we can get a dozen or so shots showing a consistent velocity in the 800-1000 ft lbs. class,  we can start moving the target back towards the fifty yard line and see how well the machine can group its shots from there.

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