[Kevin Kuehn]

Ordinary Mylar packing tape is a possibility, problem being cutting it to a custom width. I wonder if one could use a thin Cyanoacrylate glue to tack each layer at the ends? All you'll need is a couple tiny drops and that stuff will wick in a long ways. It will set almost instantly. Recommend a good hobby shop grade and not the cheap watered down variety store brands. Be cautious that if you heat CA glue with a soldering iron it can give off poisonous gas. Several years ago I got some yellow transformer winding tape from a place in Florida. It's available in any thickness you could want and they would cut it to custom widths. Back when I got mine they offered free engineering samples of off the shelf rolls.