Start with more research to understand how all this works....
The longer the resistance wire is, the higher resistance you have. I think most wire resistance is measured in ohms/ft or /m. So it would stand to reason, by wrapping around a larger object with the same amount of wraps would use more wire, thus, less wraps require for a macro coil vs micro coil using the same resistance wire.
I'd start with single coils. Figure out how many wraps to get to a target resistance.
With dual coils your resistance is cut in half of each coil. Make sure you understand the amp draw of your batteries and the amp draw of your builds.
Please be careful, this can be dangerous if you don't understand what you are doing..
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