Need quick guide to coils/resistance/etc

[BaronHarkonnen]

Hello!

I'm not new to vaping, ive been vaping for 3 years, building my own coils, so i have some experience, but i'm never figured out the reason behind some of the things

to give you an example - when i vape 2 bateries series mech mod, i just found out by experimentation what coils i need, and what resistance i need, (its about 0.21ohm for dual parallel coils). basically in mech mod to me ohm value is just a 'power' control - too little resistance and coils burn in a second, too much and i have to hold the fire button for 5 seconds before anything happens. for regulated mods ive never bothered with resistance too much. i just picked some arbitrary sub 1 ohm resistance (most of them where 0.3-0.5 ohm range), and the rest i controlled with Watt, power curves, etc.

but, now i have transitioned to MTL tank, so regulated mod is pretty warranted

so my question is,
what is the difference between say very low resistance coil + low wattage VS higher resistance coil + higher wattage? i mean in practice?
say 0.15 ohm VS 1ohm, with adequate Wattage for each to produce the same vapor effect - why would i chose one or the other? (especially in MTL context - i'm new to MTL).

for example now with MTL i have 1ohm coil (that's what came with the tank), at 35w, and its fine...but i do want to build my own coil, problem is my wire that i have now is low resistance.
maybe its not problem, but i have no idea really.

i know that different materials ramp up different, that i know, but besides that, i never figured out what different ohm in a wire really do in terms of experience unless it's a mech mod.

if someone could explain to me in a simple language what is the difference, i would appreciate!

Thanks,
Vadim

 

[sonicbomb]

With a regulated mod coils with low mass and high surface area are the way to go, 26 guage wire is a good place to start. The end resistance resistance is not really important on a regulated device. Start at low wattage and increase until you reach a happy place.
Please have a read of the articles below as they have most of your questions covered.

Understanding the relationship between power and coil resistance | E-Cigarette Forum
Ohms/Watts Law - Calculating safe amp usage | E-Cigarette Forum
Choosing a coil for a single battery unregulated device | E-Cigarette Forum

 

[icepickmaker84]

You ran a .21 build on a series mech?

 

[Zaryk]

0.21 is pretty low for a series mech. That's got about a 40 amp draw. There are no batteries rated for that.

 

[icepickmaker84]

0.21 is pretty low for a series mech. That's got about a 40 amp draw. There are no batteries rated for that.

I did the math, 336w...holy crap!! Lol!


Sent from my iPhone using Tapatalk

 

[Zaryk]

I did the math, 336w...holy crap!! Lol!


Sent from my iPhone using Tapatalk

WOW! Flamethrower....

 

[DaveP]

BaronHarkonnen, spend some time on Steam Engine | free vaping calculators to develop a good sense for what's safe in vaping your mech mod. Click on Coil Wrapping and play with the numbers.

Two fully charged 18650's gives you 8.4v with freshly charged cells. The coil resistance determines the wattage you get at the coil. For a mech, you have to vary the coil resistance to change the power to the coil and that involves coil wraps, diameter, wire gauge, and voltage delivered by the mech mod (1 or 2 cells, series or parallel).

You'd be better off using a regulated mod. That would allow you to wind a coil that hits in the mid range of vapable wattage and turn the power (voltage) up and down to suit your own personal taste. With a regulated mod you can hit the 35 W target with a variety of coil resistances.

 

[BaronHarkonnen]

You ran a .21 build on a series mech?

0.21 is pretty low for a series mech. That's got about a 40 amp draw. There are no batteries rated for that.

I did the math, 336w...holy crap!! Lol!


Sent from my iPhone using Tapatalk

WOW! Flamethrower....

View attachment 848823

I think my readings may be off (to be honest, i haven't used regulated mods in a while, and i don't make reading on mech - i just know what wire i have, and number of revolutions),
from my calculations on the coil calculator it should be closer to 200-220w. but yes - it is a flamethrower .
on DL i'm more into 1 second draw, and exhale. that's pretty much the reason i went MTL now. im coming from cigars\pipe smoking, so its all about the throat hit rather than lungs.
also i started to cough lately, and i do suspect it may be related to vaping, i use ALOT of cooler\mint (whatever its called, ive been explained that its basically some kind of acid, idk), and throat hit is really more important to me.

batteries, yeah, they probably are not happy, but so far they all endured!
i use VAPCE and HΩLIFE
i can't find SAMSUNG batteries where i live unfortunately (and could not order them online actually...)

With a regulated mod coils with low mass and high surface area are the way to go, 26 guage wire is a good place to start. The end resistance resistance is not really important on a regulated device. Start at low wattage and increase until you reach a happy place.
Please have a read of the articles below as they have most of your questions covered.

Understanding the relationship between power and coil resistance | E-Cigarette Forum
Ohms/Watts Law - Calculating safe amp usage | E-Cigarette Forum
Choosing a coil for a single battery unregulated device | E-Cigarette Forum

that's good read! thanks.
i would welcome more examples though, yesterday i decided to try my wire, and came out with 0.61 ohm, and its OK too, while the wattage is actually higher now on reg mod - up to 45w from 35w. but that's confuses me now. i mean - from physics stand point it makes sense, but intuitively i'm lost...
the only thing i can say for sure - is my batteries are draining faster now (makes sense), but i think i will want to avoid that. higher resistance apparently is the way to go...

i actually ordered a thiner wire already - 32AWG and 34AWG SS maybe that's a bit extreme, but i did not cost much, so no problem.

if i rephrase my question more specifically -
lest say i will make a coil that will be 2.5ohm, assuming the mod can take that (some of them can go to 5ohm i think) - what can I expect?
from what i gather:
i will get better battery life
i will get cooler vape
i may run into ramp problems (but power curve should fix that i suppose?)

 

[BaronHarkonnen]

BaronHarkonnen, spend some time on Steam Engine | free vaping calculators to develop a good sense for what's safe in vaping your mech mod. Click on Coil Wrapping and play with the numbers.

Two fully charged 18650's gives you 8.4v. The coil resistance determines the wattage you get at the coil. For a mech, you have to vary the coil resistance and that involves coil wraps, diameter. wire gauge, and voltage delivered by the mod (1 or 2 cells, series or parallel).

You'd be better off using a regulated mod. That would allow you to wind a coil that hits in the mid range of vapable wattage and turn the power (voltage) up and down to suit your own personal taste. With a regulated mod you can hit the 35 W target with a variety of coil resistances.

yes, that's what ive done basically, but my confusion arises from the fact that - in mech mod - i pretty much get it, i understood how to match resistance to what i wanted, what number of revolutions i need, + some trials.

my reading from calculator for example for mech mod build:
based on 7.4v, current 34A, power 250w
coil is Fused Clapton, dual coil, 8 wraps each, 4mm Dia.
ive used this configuration for a year pretty much.

now, i do want to return to regulated mod because MTL, and frankly i do wan't more control, but now i don't have that intuition - because with reg mod i can adjust the power, and curves, so i don't see where resistance comes into play really (what resistance really affects?).
when i just started vaping, my only concern with resistance was whether the mod can work with that resistance or not, and that's it.

to give an example from another field - my car has 15'' wheels, but can take 17'' wheels. for some time i wanted 17'' wheels because 17 is bigger . then i was explained that 17'' wheels = harsher ride. then i also had a chance to experience 17'' wheels ride, and yeah, it really is. so, i understand now what is the manifestation of wheel sizes on riding experience. (off cores im sure there are reasons why you may need a bigger wheel, maybe for racing, but i know that my main criterion is comfort (at least reasonable)).

thinking about that, maybe i need to mention what is important to me in vaping -
1) I would like to get a lot of taste, as much as possible (i believe nicotine content will also be at play here)
2) Vapor quantity - not very important, its just usually my experience was that more vapor = more everything - taste, hit, sensation etc. but i might be wrong, and i won't miss big clouds if i get the taste and hit without the clouds.
3) my longest inhale is 2 seconds. maybe 3 but that's rare (on MTL)
4) i do want better battery life, im tired of going with batteries in a pocket tbh.
5) conserve e-juice will be welcome as well, because now i use about 0.5-0.75L of juice a month on average. (well that's on DL, now on MTL i can't say yet).

 

[Izan]

Hola Vadim,
Since you are in Israel you can source batteries from: NKON | ru.nkon.nl

Cheers
I

 

[Don29palms]

You need to quit using a series mech mod. You are going to get hurt and it won't be good. You don't know what you are doing.

 

[BaronHarkonnen]

I think i figured it out!

so, with low resistance, it seems i'm limited by current - current goes way up on low resistance.
on the other hand, if i go high with resistance, i'm limited by the Voltage that the mod can produce.

at least i think so, because i took out my old reg mod, wismec RX300, which is rated to 400watts, but with a coil of 1.9 ohm, i can only get up to 50w. voltage read out is 9.9v.
or my mod is faulty (which i won't be surprised at all)...

so, it seems to me, that with say, extremely high resistance like 5ohm, i will be limited to vaping at about 20w. and power curve won't help me here, as it will be limited to 20w max as well...

so, from what i gather so far,
reasonable range of resistance should be from about 0.4ohm - 1.3ohm. on regulated mod that is*, assuming the mod goes up to 9.9v, and if i want wattage up to 80w-100w.

please correct me if i'm wrong

*i understand that same laws of physics apply to mech mods as well!

 

[Zaryk]

based on 7.4v, current 34A, power 250w

This is where you are confused. It isn't 7.4v, it is 8.4v. Batteries get charged to 4.2v, the 3.7v is the nominal voltage listed on the battery and not the number you use in the calculators.

 

[Don29palms]

This is where you are confused. It isn't 7.4v, it is 8.4v. Batteries get charged to 4.2v, the 3.7v is the nominal voltage listed on the battery and not the number you use in the calculators.

Agreed. Also batteries in series increase the voltage but the amps of the batteries stay the same. He's drawing approximately 38 amps on, at best, 20 amp batteries. It's an accident waiting to happen.

 

[Zaryk]

now, i do want to return to regulated mod

I fully support this decision, a regulated mod is a great idea for you.

If you ever decide to go back to mechs, please educate yourself further on their safe use. Here is some good info to read through.

(8) A Beginner's Guide to Your First Mechanical Mod | E-Cigarette Forum
(16) Explain it for the Vape Noob: Ohm's Law calculations for a Mechanical Mod. | E-Cigarette Forum

 

[DaveP]

Agreed. Also batteries in series increase the voltage but the amps of the batteries stay the same. He's drawing approximately 38 amps on, at best, 20 amp batteries. It's an accident waiting to happen.

Right on! He's in serious overcurrent conditions in series mode with a mech. We've all seen the videos where mechs turn into a small blowtorch when the cells can't handle the current.

 

[BaronHarkonnen]

Right on! He's in serious overcurrent conditions in series mode with a mech. We've all seen the videos where mechs turn into a small blowtorch when the cells can't handle the current.

I think he used his post to make his 5 post mark to gain access to all the forums and threads.

you will be shocked to know that i didn't. (i mean the 5 post mark)
ashamed to admit - but i really vaped like this. and for over a year.
honestly, i don't know how did i not have an accident yet.

 

[DaveP]

BaronHarkonnen, Check out the link below on parallel and series circuits.

Series and parallel circuits - Wikipedia

 

[DaveP]

you will be shocked to know that i didn't. (i mean the 5 post mark)
ashamed to admit - but i really vaped like this. and for over a year.
honestly, i don't know how did i not have an accident yet.

We may have been hard on you, but we just don't want anyone to experience the mech accidents we've seen on YouTube. Once the cells go into meltdown you will certainly get burned. If it's in your pocket when that happens you'll get a 3rd degree leg burn and that can mean you lose flesh on your leg and on your hand trying to get it out of your pocket.

Mech meltdowns are a serious threat when they happen. We want you to be safe.

ETA:
@BaronHarkonnen, pick your cells from Mooch's battery tests and evaluations here. He's the battery test and ratings guy for e-cigarettes across the board. The ratings put out by vendors and other sources are sometimes over-rated. Mooch posts the accurate results of actual testing done on his equipment.
List of Battery Tests | E-Cigarette Forum

 

[BaronHarkonnen]

We may have been hard on you, but we just don't want anyone to experience the mech accidents we've seen on YouTube. Once the cells go into meltdown you will certainly get burned. If it's in your pocket when that happens you'll get a 3rd degree leg burn and that can mean you lose flesh on your leg and on your hand trying to get it out of your pocket.

Mech meltdowns are a serious threat when they happen. We want you to be safe.

its all good! I'm glad that all of this came out, and it was the right thing to tell me those things! i will take it as an opportunity to learn.
embarrassed a bit - for not investigating the subject thoroughly, and for blindly trusting 'mech specialist' in a vape shop who taught me how to work with mech. (one of the reasons btw that i was dead sure battery voltage in series is 7.4v...). should have investigate it myself really...
but, i guess its better to find out sooner rather than later!


BTW thanks to everyone who participated, i will put the valuable lessons to good use!