Sub Ohm vs diy coils

Hi everyone,

Small question that has bugged me for the last 2 weeks and maybe being asked be4 so do not shoot me :wink:

Howcome my aspire cleito or smoke TFV8 have such a wide range of power (W) you can use ?
Example R = 0.4ohm , and stated by aspire you can use it in a range of P = 40W - 60W ??

When i make my coils in my serpent mini i apply Ohms Law.
Build end up with R = 0.2ohm - 0.4ohm , but ohms law applyed i end up with P = 32.0W max.

Does anyone know howcome subohm coils still last this long ( week ) while they clearly are overcharged?

Thx for your time :wink:

Ohms law does not apply in the same way with a regulated mod. The resistance does not effect the amp draw in the same way. Amp draw in a regulated device is determined by the chip and not the coil. The design of the atomizer will mostly dictate the minimum and maximum wattage. Minimum is determine by the mass of the coil. How much power does it take to heat the coil to the point of producing a usable amount of vapor. The maximum is determined by the coils inner diameter, wire thickness, juice flow capacity and amount of airflow that the coil has. All of these will determine how many watts can be used before the heat becomes to much for the wire to handle or the e-liquid/airflow ratio to keep the coil from overheating to the point where it burns the wicks.


Thx for your explenation @louiesquared

So in other words, if i place my serpent mini onto a regulated device (like the iStick Pico where i have it atm) and i go above the calculated amount of W , it wouldnt burn the coil nor burn the cotton inside the RTA ?

1 Like

It depends on the coil. A simple 5-6 wrap 26 gauge round wire coil at 3mm ID will probably not preform well above 30-35 watts but a 24 gauge at 3.5mm ID should be fine at 40 watts. I run 2x30GA / 40GA fused clapton with a3mm ID and 5 wraps in my Serpent Mini with about 50 watts. I prefer a really warm vape. When you get in to higher wattage builds your wicking has to be just right. Too much and you will burn the wicks fast but too little and the tank will leak.

1 Like

The best advice I was given a long time ago and I give yet today is start low and work up until the flavor starts dissipating and the vape starts drying out. Don’t push it to a total dry hit. You can tell as you are approaching that condition. That will depict your power range. Like @louiesquared wrote, It’s a combination of most everything you have going on inside the atty. Are the wicks keeping up to the amount of liquid being vaporized. Is the airflow in combination with the liquid keeping the coils cool enough to not burn the wick. Etc, Etc, Etc.


Also, a little something I noticed, when my curiosity got the best of me in the early days of vaping (in other words, I cracked a few open to see what makes’em tick) most pre-built (drop in) coils are much thicker in diameter than the wire I regularly use for the same resistance. Plus most have a diameter way higher than I would try to wind a coil, like 4mm.
Plus the wire looks like they were dipped in some other type of low melting point metal.
This was all discovered on the old herakles sense coils.


In addition to what others have said, it’s been my experience that most companies grossly overrate the wattage capabilities of their coils-Most of the time I’ve found that their lower power rating is the maximum that I could push through the coil. I’ve been building for over two years now, so maybe that’s changed a little bit since I last bought a tank that uses pre-built coil assemblies.

When it comes to RTA’s, I’ve found that wicking plays a HUGE part in how hot you can run your build with wire diameter being second and the material being used following behind. I mostly build with 26 gauge 316L SS, running dual 2.5 mm 9-wrap spaced coils and typically run them in the 40-48 watt range. Anything above that and the wicking just won’t keep up with the heat generated by the SS wire. If/when I run kanthal or nichrome, I typically have to run them a little hotter to acheive the same vape I get with the stainless.

The fact that there are a variety of variables that you can tinker with is what keeps me building-That, and the fear of buying another sheet of bad coils…


That actualy quite narrows my problem down what i am having, with the smok TFVA (subohm) i do have quite warm vapes and i am missing thing alot with the serpent mini but it seems i still have some stuff to learn,reading all this difference between the thikness & gauge… i cannot seem to get my sum (calculation) above 34W …

Thank you all for sharing your toughts :+1:

1 Like

Those smoke coils have a lot of wire in them. If you want a coil that can handle ,more power I would suggest using a clapton or fused clapton to get that warmer vape.