The purpose of the coils is to create surface area for heating the liquid, as well as increasing the effective resistance in a given volume. You do not want adjacent turns to short together! Stainless steel wire, IIRC, is used with a temperature-controlled box mod and runs at a higher temperature than kanthal. The temperature is derived by "measuring" the resistance of the wire, using the same microprocessor that is controlling the current. The 2.97 ohms per meter for "juggernaut" stainless steel wire is valid only at room temperature. It increases as the wire gets hot, which allows the microprocessor to infer its temperature by "measuring" its resistance: R = E/I.
Why do adjacent, tightly wound, turns not simply "short out" and produce an absurdly low resistance? There are many factors affecting the actual end-to-end terminal resistance, including surface oxidation, contact geometry, and how much pressure there is between adjacent turns. In any event, it would be most prudent to actually measure the coil resistance after winding the coil. This is easily accomplished by momentarily passing a known current through the coil and noting the voltage drop across the terminal ends. For low-resistance coils, this "test current" should be several amperes to allow for a reasonably measurable voltage. For example, ten amps through a tenth ohm coil would produce one tenth volt or 100 millivolts, easily measured by most digital multimeters. If you leave the current on long enough to heat the coil, you should see the effect of temperature on the coil resistance.
Potentially disastrous then. Good job I posted here first.
Yes, there are a few vapers here who build (or try to build) their own rigs. I didn't, preferring to use off-the-shelf commercial rigs purchased as a name brand
(Eleaf iStick Pico) from a reputable vape shop in Dayton. I started vaping in 2011, on the recommendation of a hospital doctor, after I experienced congestive heart failure and was hospitalized. Unfortunately, I have had to give up vaping since moving to Florida, after experiencing a heart attack that required open-heart coronary artery bypass graft surgery. Not saying smoking or vaping had anything to do with my heart problems, but nicotine does constrict the arteries so I finally gave it up this year. My heart needs all the blood flow it can get!
... I tried to make a big coil with 350 micron wire and I simply could not power the 6ft of cable needed for a tri-core braid, so I am exploring other options. It's not just power here, it's about space. The deck is not designed to be used with just one coil, so locking two together seemed to free that space up as they are both going from, and go the same terminal.
You lost me there... why would you need to power six feet of cable? And what is tri-core braid? Is this drip vaping with the goal being to produce prodigious quantities of "smoke" vapor? When you get to this level of vaping, is nicotine still a component of the vaping liquid, or is it all about "taste" and "back of the throat" feel without the need to satisfy nicotine cravings? Just curious. Seems there is a vape shop in every strip shopping plaza here in Venice. Not sure who the customers are though, because I don't visit vape shops anymore.
Anyway, if you really are intent on interlocking two identical four-turn coils, try my suggestion of using pieces of mica insulation between the turns to keep them from shorting out to each other. There will be hardly any voltage between the turns, so very thin pieces of mica, which are easily flaked with a single-edge razor blade from a thicker piece, should work fine. Perhaps you can slightly expand the coils to make room to slip the mica between the turns, and then compress the coils back together with a small vice or pliers. And be sure to measure the resistance of the final result. That's how you prevent disastrous things from happening.
Have you paid any mind to how you plan to control the discharge current from your re-chargeable lithium ion battery? This is NOT a trivial problem and usually involves a MOSFET and pulse width modulation with some sort of current, voltage, or combination feedback, usually mediated with a microprocessor.