High ohm high watts v low ohm?

[Cowboy192]

Trying to figure this out, I know people built low ohm coils to get higher wattage and bigger clouds on a mech due to battery limitations,
but with vw devices and powerful mods I was looking at trying going the other way,
i am thinking of doing a build as
.27mm 9 wraps per coil, duel coil (2ohm per coil) to run at 1ohm and 25w
would the increased surface area of the coil not give a bigger cloud than say a low ohm coil with only 3-4 wraps?

 

[ian-field]

Trying to figure this out, I know people built low ohm coils to get higher wattage and bigger clouds on a mech due to battery limitations,
but with vw devices and powerful mods I was looking at trying going the other way,
i am thinking of doing a build as
.27mm 9 wraps per coil, duel coil (2ohm per coil) to run at 1ohm and 25w
would the increased surface area of the coil not give a bigger cloud than say a low ohm coil with only 3-4 wraps?

IME; anything under 1 Ohm gives a burned liquid taste - more surface area can only be better.

 

[bussdriver]

I'd have to believe you are absolutely right. If you compute the heat delivered in watts related to the surface area of the wire, a smaller coil will run hotter. Personally I prefer more turns in my coils, compared to fewer. The wicking must also be able to keep the coil well supplied with juice.

Just be sure your mod can deliver the voltage needed. A low ohm coil may draw a lot of current and get really hot, but that same voltage on a higher ohm coil won't do nearly as good. Some mods can deliver lots of watts to those sub-ohm coils, but their power delivery usually falls off quickly at higher voltages.

Higher ohm coils work well on regulated mods, but they are useless on mechs.

 

[Rsunderl]

From what I've read, asked about and experienced in my limited experience with coil building, yes, more surface area produces bigger clouds.

That's because there's more liquid being vaporized at any given time.

 

[State O' Flux]

A "low ohm" build doesn't have to be a small surface area... if you have sufficient wattage output to support it.

If your VW device's upper limit is only 25 watts (vs. a basic 18650 mech mod, with an output potential of 125 watts, or more)... that is your limiting factor.

If you utilize the often overlooked "heat flux" (radiant coil heat measured in mW/mm²) value adjustment found on Steam Engine (click sigline hyperlink below)... you can model wire gauge and resistance value to produce a build with specific temperature range parameters using a desired wattage output value.

Some examples...

Your "0.27mm" (or 29/30 gauge) 9 wrap, 2mm ID, 2.0Ω per coil / 1.0Ω net dual parallel build at 25 watts... would have a heat flux of 222 mW/mm².

A 24 gauge, 12 wrap, 2mm ID, 0.8Ω per coil - 0.4Ω net dual parallel build at 80 watts... would have a heat flux of 221 mW/mm².

It's a relatively simple matter to develop an 'optimized build', with a desired heat flux, using the current output you have available to you... but yes, at only 25 watts, you do have some net resistance / wire gauge / surface area limitations.

Cheers!

 

[Robert Dupre]

Really for these high wattage mods out there as long as you arent below the resistance requirements it doesn't matter what it is i use 24 guage in my rda. On a mech i keep it at between .3 to .4 ohms but on my ivp3 i will up the amound of wraps of the coils to as much as double and up the wattage to be able to still heat that i go up to 100 watts but pretty much not less than 60 for those and it performs as good or better than a low resistance coil in my mech.

 

[Cowboy192]

I did use the heat flux option on steam engine to arrive at the 25w, I was just curious as I can run up to 50w, I may give it a try on my plume veil next time I get the urge to start building coils (then chuck in some of my 80/20 vg/pg for giggles)

 

[tj99959]

Any more the size of a cloud is controlled by the capacity of a persons lungs, not low ohm or high ohm.

 

[IXIShogunR1]

i just use the steam engine and the heat flux calculator then i set it to the watts i want to run or can run and aim for 170-190mw/mm and thats my preferred heat range
so for my IPV3 its 26ga wire at .5-.6 ohms running 50w
my IPV mini is 28ga wire at .5-.7 ohms at 30w