i just made a tail for my swimbait out of 2mm closed cell craft foam. i used it beceause its cheap, flexible, pretty durable, i have a lot of it, it fits perfectly in the slot, and it can be easily replaced if the fish tear it up too bad.
my only question is, do you think having such a large piece of foam on the end of the small tail section will affect the action of the bait. im afraid that the foam will want to lay flat on the waters surface instead of being vertical like the tail should be.
i guess if it does affect the action too much, i will just rip the tail out and either go tail-less or find a new material.