I recently discovered the benefits of using old bands as stringer spike or spearpoint protection and thought I'd share some pics of my two stringers, one for the belt/waist and one for a float. I'm sure my mods aren't new, but at least now there are some pics and explanations out there on how to do it
The float stringer is made from a loop of monofilament with a small tuna clip put into the loop before it was crimped shut. Then I put the crimped end of the loop into the old band to form a spike protection and keeper. Now just connect the stringer to the small tuna clip and put the spike into the old band rubber. This way the stringer can unclips from the float very easily and the old rubber band protects the float and other stuff from puncture when it's not in use.
The belt stringer is similar, but I used a smaller, less obtrusive pigtail swivel to attach the stringer on. the pigtail is tied onto a loop of stretchy cord, for attachment to the belt or any kind of clip. This provides stretch and tension for a stringer that will hug your waist well to not flop around too much. Again, I used an old badn to form the spike keeper, which can be attached to the belt or a clip.
I made the rubber protectors/keepers so long so they would be easier to operate in cold water with 7 mm, three finger mittens. If you dive with thinner gloves it is probably a good idea to shorten them, especially the belt stringer version, in order to get some more space on the stringer for stretching around you waist.