The first ones I tried to make didn't turn out well either. I think the tubes were from a mountain bike or something. They were considerably thicker along one edge than the other, which might be a good thing for biking but isn't so good for the ranger bands. The next ones I made were from a regular 10 speed tube. I just bought it at Walmart for about $3.00 and I've still got plenty left. They are very useful items. I now have them stashed all over the place.

Regards, Vince