I never saw the original message thread, but it can give you a pretty good grip. Just like rubber soles on shoes, that rubber makes a good grip - especially when wet.
Cut your innertube in long narrow strips. Hold one end onto your knife handle, then start wrapping around your handle pulling/stretching the innertube. Spiral wrap it down around your knife handle. When you get to the end, figure out a way to attach it - tacks, glue, wire, etc. You could glue one wide piece around the whole handle at once, but that spiral wrap gives you all those little edges for extra grip. And the rubber adds a little cushioning.
But it also adds more bulk. Car and truck innertubes are fairly thick, and will add a lot of bulk to your handle quickly. Bicycle tubes are much thinner, stretch easier and more, and tend to work better.
You can cut long strips by doing a spiral cut around the end of your innertube. Cut your innertube completely through. Then start your long strip. Cut in at a slight angle until you are in as wide as the stripe you want. Then cut parallel to the edge as you go around the innertube. You can then cut a strip as long as you need, or until you run out of innertube.
Just my humble thoughts to share. I hope they help.
Mike
