I think I actually played this one quite a bit. I put Friction Stickers over the Brake Pads after carefully filling in the teeth on the Break Pads with the the cork pieces left behind when you peeled the backing off.
I put the small washer between the two bearings to make a better slot for the string to nestle into.
I don’t know how I managed to not strip it out!? I didn’t change the axle!
Of course the finishing touch; which is way more sophisticated than machining metal rings like @yoyodoc did , was finding the right size rubber o-rings.
Fair enough, only remembering what I saw in an article about the mongoose being a considered a rip off the viper, ( even the name mongoose was a jab at the viper) and Henrys responding with an infringement suit, perhaps lawsuits were only threatened? Eitherway, was only trying to remember the story behind this as requested by the poster.
The way I heard it, Tom Van Dan Elzen made the Mongoose as a bit of a jibe at Henry’s. Henry’s had the patent on the rubber rings… That was just a story, though, I don’t know how true it is. It certainly is pretty funny that he named it the Mongoose, and put all those patent numbers prominently on the hub!