This time I have a more cunning plan to defeat the chaffing trolls.  Five wraps of  heavy Dacron upholstery fabric now protect the precious nylon rope from abrading away under the immense pressure from the steel crossbar.  The point of failure in the previous set of all leather wraps appeared to be at specific pinch points located at the ends of the crossbar.   The juncture between the crossbar and the vertical ear was able to  grab the soft suede and then elongate it to the point of ripping.  After that, the nylon rope was able to pop through the tear and make direct contact with the steel.   That was all the invitation those little nibblies needed to start munching on the spring.  They don’t really come out of hiding until the linear tension on the spring is at its highest.   If Firefly only engaged in low power shooting,  it  wouldn’t be a problem.

When we get around to trying springs made from nylon thread,  rather than the 3 strand nylon rope we are currently using,  I’m thinking the first few layers of thread contacting the steel will probably get eaten through.  I suspect that the resulting shredded fibers may serve to protect the rest of such a spring and perhaps obviate the need for all this fancy anti-chaffing gear.   With 3 strand, if one of the ropes  pops under the load,  it compromises the  linear tension in the spring and throws off the balance between the two halves of the machine.  Very uncool for anything but rudimentary shooting.

Not only is this new fabric highly tear resistant, but I suspect that having multiple wraps that can slide over one another, will also help to defeat any pesky pinch points.   The chamois leather outer wrap is really just for aesthetics.  It wouldn’t do to have Firefly looking like a tweedy something salvaged from Sherlock Holmes’s wardrobe.

At the time of installation, I was able to slip some heavy steer hide collars around the crossbars and up against the slotted ears on the washer assembly. This, and the new fabric wraps,  seem to be an obvious improvement over  previous attempts.   If I were not philosophically opposed to soppy storms of regret,  those earlier versions would be prime candidates to weep about.

No need to blither on about this anymore.   It’s all really quite elementary, my dear Watson.

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