Was thinking this evening: what if I heat the coil under the flame of a propane torch? Might not be the temperature needed to properly oxidize Kanthal A-1 and have a layer of non conductive aluminum oxide migrate / cover the surface. But might make the coil less conductive instead of non conductive.
I tried with 28 AWG since smaller might "burn and snap". Gave the coil a long burn in the hottest part of the flame. Coil came out grey, non reflective. Tested with a cheap handheld multimeter. Got surprising result: would not conduct. Nothing. No reading. On brand new wire, I get a reading. So I guess it did help.
Huge coil I have: 9 wraps on a 3 mm wick. Reads 1.9 ohms. Takes a while to heat up at 4.2 V. But no hot spots at all, no short, nothing. Easiest setup I've made yet.
Very interesting! I will give it a try. I guess you must have got it almost white hot...thanks for the info.