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Artful Coils: How will changing the shape of coiled wire change the resistance?

hi to all, as a newbie in vaping, the first thing that appeals to me is its structure, so I want to ask some help. The situation is following, "Vape Mods" are a type of atomizer used in e-cigarets. These "mods" can be built basically from scratch. The simplest mods consist of little more than a battery and a coil shorted over the battery drenched in a vegetable glycerin(VG) and propylene glycol (PG) mixture soaked into an organic cotton or silica wick. The circuit is completed when the button is pressed and the coil (often made of nichrome wire) atomizes the PG/VG mixture into vapor.

Vaping has created a diverse DIY community, and intense interest in Ohm's law among many people who might not have other wised been at all curious about electronics.

Here is an Ohm meter designed especially for vaping atomizers.
8m8KA.jpg

Coils come in many shapes and designs. The shape, length and thickness of the nichrome wire changes the resistance of the atomizer. The shape of the coil also has an impact on wicking and vaporizing the PG/VG mixture. The coils are often hand-made and designs are shared over the internet.

Here a is guide showing the basic relationship between coil diameter, wire length, wire gauge and resistance.
4RgcI.jpg

But what about something like this?

There are effectually two coils in parallel and one of them is made of smaller coils.
Rutbx.jpg

In theory, any resistance can be reached by having a wire with no coils of the correct length. I would not be effective for vaping, but as I understand it, the only important variables when calculating resistance are the diameter and length of the wire and how many other wires are in parallel or series.
QCkWl.jpg
ubXs7.jpg

But, is that really the whole story? Some of the time a coil touches itself. Wouldn't that make it, effectively, like a lower gauge wire?

And these coils are effectively inductors. Will that have any impact? I suspect the inductance is too low for this to matter, but it's something that I've always wondered.
Thanks all.
 

HondaDavidson

Gold Contributor
Member For 4 Years
Electrically fancy builds work the same a plain ones...... performance determined by amount and type of material.

Vaping performance is only partially dependant on electrical pergormance. In fact they are not even mutually dependant. ... don't need perfect electrical function to get great flavor....... sometimes best requires bending if not breaking RULES. Or at least performing beyond designed or perceived limitations.

Sent from my SCH-I605 using Tapatalk
 

gbalkam

Gold Contributor
Member For 4 Years
ECF Refugee
Reddit Exile
There are effectually two coils in parallel and one of them is made of smaller coils.
What you actually have, is 2 identical coils running side by side in parallel, wrapped with a layer of wire. Basically a dual core clapton, then wrapped with a 3rd wire (the larger silver one).

in this case, it is the 2 inner parallel coils that provide the resistance, carry the current and provide heat. The outer wire used to wrap may carry some current, but so little that you don't need to count it. Remember, electricity flows across the path of least resistance. This is also why it is important that your core wires are identical. Dual core lowers the coil resistance.
 

µDavid

Member For 3 Years
I got severe ADD so I didn't read the post but just from the threads topic I'd like to point out that the resistance of a wire may change if bent(but this doens't happen until it is bent back and forth a few times) but as the metal starts to break and fracture the resistance aught to rise.
 

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