Thanks, Todd. I have a problem with the cling film (plastic wrap) solution: It clings! I was adding cling film, inserting it to see how it looked, and then I found that I couldn't extract it! It's clinging to the wall of the blade, and pulling the Ultraedge diffusing film away. It's too bad, because it was looking pretty good, but on one side, the LEDs are all sharply visible as individual points of light. A layer of diffusing foam could have fixed it, but I am literally stuck.
I don't recall the length of the Hyperblade nylon tube. I cut it down, and didn't note the original length. Sorry.