Eric, When cutting the zip ties if you cut the ties 90 degrees from the direction that you cut them, it will minimize or eliminate the sharp edge so you don't have to file it down.
Out of passing interest, to put a loop in the end of Bungee... there is a knot called the 'Angler's loop' (see Wikipedia) that works well. It is one of the few knots that's reliable in Bungee; most others 'crawl' out over time.
Great Idea I am glad I found your site . I am like a lot about to build my own canopy from pvc . One shrink tube replacement or alternative could be bike inner tube it would have to be the racing bike inner tube
I would be very careful with bungee cords. My friend had one come apart hit him in the eye and now his iris will not function as it should. A knot called the 'Angler's loop' (see Wikipedia) that may work well.
Nice and simply instructions,really good presentation to the point.Thank you I will be using this to make a set of chain stays to keep my tire chains on my snowblower :-)