Self Fusing Electrical Tape Question

[Mace Canute]

That layer needs to come off, I imagine. I use a lot of that stuff for making stiff rigs for my trolling lures (Marlin stuff) and end up using the hook point to help separate the layer from rubber tape. I imagine that is what keeps the tape from bonding to itself while on the roll, although to get a really good bond, you need to stretch it out over itself.

I've used West Marine brand stuff and the 3M stuff...

That's exactly right. Self amalgamating tape has to be stretched to activate it. Stretching it until it's about twice the original length and about 2/3 of original width works quite well. I've used more of this stuff than I care to remember doing splices on underground electrical cables. We always used plain jane electrical tape over it for a physical protection.