Resistance lowers as you add strands of wire to a wrap.
2 strands of any gauge wire will end up with a lower resistance per inch or whatever unit of measure you prefer.
Add another strand and the resistance will drop even farther.
Exactly how much is dependent on a bunch of factors; how tightly you wrap the wires together being the simplest of ways to describe all that is going on. In the end you want a tightly wound wire without any open loops, if you get open loops they will likely become hot spots.
I run 4 strands of 32 gauge kanthal a1 more often than not, first wound dual strand then folded and wound again. The result is about the same diameter as 28 core wrapped in 32 guitar string style maybe a little less. With wire this thick most coils are going to be in the sub ohm range, dual and triple wire wraps can easily be made into low 1.0+ ohm coils, the quad wrap would need to be really tiny and that's not particularly easy with how thick it is. It could be done I suppose, there are some highly creative people out there building neat nano coils.
This style of making coils works really well with an ultra fast wick method. If your having issues getting enough fluid to the coil it isn't going to result in a good vape.
As for why someone would do this, in my case I initially purchased 32 gauge kanthal a1, for me wrapping the wire gave me options beyond the resistance the wire in single strand form.
When it comes to vape quality, like I said before, if you can get
juice and enough watts to the coil fast enough, wrapped coils throw plenty of vapor.
Just remember the lower the resistance the faster your battery is depleted, and depleting a battery faster than its rating will damage it. The result can be catastrophic failure resulting in injury to self or others.
There is plenty of information on this forum about how to determine if you are over your batteries limit, and calculators abound on the internet.
I'm no safety monger here, but there are some serious risks involved in going outside of the standard single wire coil type builds, for example if you do have a hot spot that burns out that portion of the coil and it shorts the device, you will have an issue in an unprotected mod. Be as safe as you need to be so you don't end up on the news and screw it up for the rest of us
seriously.
If your not happy with your current rig, read up about your device, batteries, and build something that has a good safety margin, don't be a hero and push the limits of your battery, that's where folks get into serious trouble.
Maurice
