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Have some questions about ohm's law.

Kiicki

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I have for some reason always tried to build a specific ohm. I usually always make 1.8 ohm coils, because I felt like Sub ohm was to harsh for me. It made me always cough, and my first tank (Nautilus mini) used 1.8 ohm's and I really liked it.

Did some reading and talk to some people, and they don't understand why I prefer 1.8 ohm.
If I have a regulated device (which I do) I can just adjust the wattage up or down to get a warmer or cooler vape with the resistance of the coil I have.

So with a regulated device, there was no reason why I should avoid sub-ohm coils. I can just adjust the wattage lower, and I would get a cooler tank right?

So it got me thinking. Why would starter kits offer two different resistance coils if they sell a regulated device in the package? For example the Subtank starter kit offers .5 and 1.2 ohm, and they offer a regulated device, so what is the purpose of two different coils? Couldn't I just add some power to the 1.2 ohm coil, to get the same vape experience as the .5 ohm? Or lower the power on the .5 ohm to have the same experience as the 1.2 ohm coil?

Is it just a marketing strategy?

I'm familiar that I should be aware what resistance my mod can read. .2-3.0 ohm is what my mod is reading I think.

Isn't resistance of a coil really important for unregulated devices and not regulated devices?
I'm also aware that if you want a warm vape, you should build a high ohm coil, if your mod can't offer you high power (Wattage)

But let's say your mod can offer the power you need to get the same warm vape as a .5 ohm if you used 1.2 ohm.

So why are so many people obsessed with "Sub-ohming" when they have a regulated device?
If I want the same warm vape as a person have with .5 ohm with 15 wattage for example, I could easily get the same warm vape with a 1.2 ohm coil, if I just crank up the wattage. (If my mod of course offers the power that it need)

Like I really don't understand why I always make 1.8 ohm coils. Couldn't I just make a .5 ohm coil and lower the wattage? This was just something I started to think about because I'm about to make my first "Clapton" coil.
I could just use another guys build, build the same thing (without thinking that I want 1.8 ohm) and adjust the wattage based on the resistance I have on my coil.

I will of course be aware that I don't build to low so the mod can't handle the resistance and the way around.
I'm I thinking compliantly long? Sorry for the long post, but something doesn't seem right to me.

So when it comes to resistance of a coil, it mostly matter for people that have unregulated devices. Not for people that have regulated devices, since you can adjust the power based on the resistance of your coil right?

I mean, why do people really want to build a .2 ohm coil for example on a regulated device? How warm of a vape do people really need? Even people with a 200 W mod wants a low ohm coil. Couldn't the just build a higher ohm coil and crank up the power? They do have 200 W for a reason.

EDIT:
For me it seems like for example the Subtank starter kit is just a marketing strategy when they offer .5 ohm and 1.2 ohm.

Let say I use 26 Gauge Kanthal. 2 mm diameter and 4 wraps = 0.5 ohm
To get a warm vape for example: Heat flux =443 mW/mm² would be at 25 W

To get the same warm vape with a 1.2 ohm coil I could just crank up the wattage to 30 W.
If the 1.2 ohm coil was made with = 28 gauge Kanthal, 2 mm diameter, 7 wraps.

And the Subtank mod can easily handle 30 W. I think it goes up to 60 W or maybe even 75 W. Don't quote me on that. But would this two setups just be the same?

The heat flux is just the same in this two examples. Isn't the Heat flux what really matters when it comes to vaping? If you want a cooler or warmer vape?

So there are many ways to get a warm vape. Lower resistance, higher wattage. And warmer vape = More throat hit, More vapor.

Cooler vape = less throat hit, less vapor. Some even say more flavor, which I think is not true. But that's just a personal opinion.

So how I see it, the two last examples I used, gives the same performance. (.5 and 1.2 ohm example)
But how would the battery drain be like? I guess it's obvious that 30 W will drain the battery faster than 25 W, but they are two different resistance coils, so I'm not sure after after all if they both drain the battery equally fast, or would the 30 W drain the battery faster than the 25 W?
 
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OBDave

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Wow, that's quite an ask here...let me try to break it down.

While to a certain extent regulated devices allow you to fine-tune your vape, having a coil resistance in the ballpark of what you're looking for is still important - I've found clearo manufacturers (and tank/clearo combo manufacturers) will ship with a handful of different coils (sometimes including nickel coils that are ONLY suitable for use with temp-limiting mods) to allow a new user to try out a handful of different vaping styles before settling on what they like best and buying the refill 4-or-5-pack in the style they prefer.

If you're trying to push 10 watts through a 0.2 resistance coil, for example, you'll never get it hot. And if you try to push 50 watts to a 1.8 ohm coil you'll probably melt the legs and kill it on the first fire - meanwhile that 1.8 coil would love 10 watts and the 0.2 is probably humming along just fine and asking for more power at 50 watts.

You're right in that resistance is much more important on a mechanical device than a regulated one, as a mech is only capable of doing one thing - delivering as much power as your battery is physically capable of providing. Build too high and your battery won't give you a good vape, build too low and your coil could demand more power than your battery is physically capable of providing, creating a rather nasty and hazardous situation.

I'm personally not in the camp that shoots for really low sub-ohm builds on a regulated device - I'll sometimes end up in the 0.2-0.3 range, but I generally prefer 0.5-0.6 builds, as it allows me to use more wire (extra wraps/bigger coil inner diameter) - more wire contacting wet wick = more vape, the way I see things. I can always turn up the power to decrease ramp-up time, though I rarely top 70 watts.

The issue with cranking up the wattage on higher-resistance coils is that they're generally built using thinner wire, which increases the likelihood that you'll just end up burning your wicking material in the quest for a hotter vape. Lower-ohm coils have fatter wire that can handle the heat distribution better, decreasing the likelihood of burning.

Am I making any sense, or getting close to hitting on what you're asking? Maybe a move to the coil discussion subforum would get you some more intelligent replies than what I've got to offer, will try and do that for you now...
 

Kiicki

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You do make sense, but I'm still wondering about something. Even though thicker Kanthal wire will handle heat better since it's thicker, why would it still melt if you use high power on a thin wire? I understand the chances of melting is bigger with a thinner wire, compared to a thicker wire.
But still, Kanthal starts to melt on minimum 1400 C, according to Wikipedia. So even thin Kanthal wire should handle higher heat?

I also understand that there's no point to build high ohm's if you want a warm vape, if your mod can't provide high power, so the high ohm coil can give as warm vape, as a low ohm coil. But let's say your mod can deliver the power it needs to get your high ohm coil warm. It would still be just as good as a low ohm coil. The only negative thing about doing this as I see, is that your battery will drain faster because you use more power to get your higher ohm coil warm.

You said you don't usually build low Sub-ohm coils (.2-.3 ohm) for me, that's low. But that's just me.
How I see it, low ohm's gives you warmer vape, and pretty low ohm's won't even get you a cooler vape, even on low power. So why not just increase the ohm, and you could vape cooler or warmer if you like. Not only warm. If you want a warm 1 ohm coil for example, crank up the power. It's that easy.

I see that people own box mods with 200 W power and they still build 0.1 coils for some reason. This is something I don't understand. Why do people buy 200 W power mods, and build 0.1 ohm? Would you ever going to use 200 W on a 0.1 ohm coil? Wouldn't that burn you? That's just way to hot.

You could either build higher ohm's and actually use the power you bought, or build 0.1 ohm coils, and buy a cheaper mod with 60 W or something.
Ohm's is just a resistance, right? So you could just adjust the power according to the coil you build, as long as your mod provides the power you need.

Normally I build 1.8 ohm coils. I like a more cooler vape, but it wouldn't be a problem for me to have a warm vape if I wanted. I can just crank up the power and there's it is! The down site of doing this, compared to actually build lower ohm's is battery drain, because I wouldn't need that much power on a lower ohm.

I still don't completely agree that if you use 1.8 ohm coil, and vape on 50 W, it would melt the legs. I have never done it though, but as I mentioned earlier, Kanthal should start melting on minimum 1400 C.

Did you personally try 1.8 ohm on 50 W and the legs melted, or is it some kind of a rumor?
I will take your word if you have personally tried it yourself. But as I see the number when it comes to melting point, it really doesn't seem right.

Sorry for the long reply.
 
You do make sense, but I'm still wondering about something. Even though thicker Kanthal wire will handle heat better since it's thicker, why would it still melt if you use high power on a thin wire? I understand the chances of melting is bigger with a thinner wire, compared to a thicker wire.
But still, Kanthal starts to melt on minimum 1400 C, according to Wikipedia. So even thin Kanthal wire should handle higher heat?

I also understand that there's no point to build high ohm's if you want a warm vape, if your mod can't provide high power, so the high ohm coil can give as warm vape, as a low ohm coil. But let's say your mod can deliver the power it needs to get your high ohm coil warm. It would still be just as good as a low ohm coil. The only negative thing about doing this as I see, is that your battery will drain faster because you use more power to get your higher ohm coil warm.

You said you don't usually build low Sub-ohm coils (.2-.3 ohm) for me, that's low. But that's just me.
How I see it, low ohm's gives you warmer vape, and pretty low ohm's won't even get you a cooler vape, even on low power. So why not just increase the ohm, and you could vape cooler or warmer if you like. Not only warm. If you want a warm 1 ohm coil for example, crank up the power. It's that easy.

I see that people own box mods with 200 W power and they still build 0.1 coils for some reason. This is something I don't understand. Why do people buy 200 W power mods, and build 0.1 ohm? Would you ever going to use 200 W on a 0.1 ohm coil? Wouldn't that burn you? That's just way to hot.

You could either build higher ohm's and actually use the power you bought, or build 0.1 ohm coils, and buy a cheaper mod with 60 W or something.
Ohm's is just a resistance, right? So you could just adjust the power according to the coil you build, as long as your mod provides the power you need.

Normally I build 1.8 ohm coils. I like a more cooler vape, but it wouldn't be a problem for me to have a warm vape if I wanted. I can just crank up the power and there's it is! The down site of doing this, compared to actually build lower ohm's is battery drain, because I wouldn't need that much power on a lower ohm.

I still don't completely agree that if you use 1.8 ohm coil, and vape on 50 W, it would melt the legs. I have never done it though, but as I mentioned earlier, Kanthal should start melting on minimum 1400 C.

Did you personally try 1.8 ohm on 50 W and the legs melted, or is it some kind of a rumor?
I will take your word if you have personally tried it yourself. But as I see the number when it comes to melting point, it really doesn't seem right.

Sorry for the long reply.

You will break you coil if you are trying to fire a 1.8ohm (say 32ga wire) coil at 50w. Thin wire doesn't have the surface area to release the heat energy like thicker wire does so the wire will rise to an extremely higher temperature and fail. I wouldn't recommend trying this out for yourself.
 

Kiicki

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You will break you coil if you are trying to fire a 1.8ohm (say 32ga wire) coil at 50w. Thin wire doesn't have the surface area to release the heat energy like thicker wire does so the wire will rise to an extremely higher temperature and fail. I wouldn't recommend trying this out for yourself.
Is there a site where it says how much power i can put into each wire size? Like, where can I read up on how much power a 28 Gauge Kanthal can handle?
 

robot zombie

Silver Contributor
Member For 4 Years
I think @OBDave pretty much covered it.

I don't know about melting the legs. I've never popped a wet .5 coil with 28g on my series mod, which pumps 8v into them. I will say that dry hits can be a real problem with builds like that, though. At the very least, hot legs are going to be a thing.

Another big reason why people sub-ohm has to do with the power limitations of regulated boxes. Voltage, man. Voltage. The highest you can build to hit the maximum wattage on a 150w (generally 7.5v max) or 200w (usually 8.5v max) box is going to be around .3 ohms. Something in the range of a high .2 to low .3 is going to give you the widest range of power levels.
 
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OBDave

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Speaking just to melting legs, when I've done it it's been with thin wire (28 and 30 gauge) and usually poorly built coils (just getting into mechs a couple years ago). As @robot zombie mentions, though, hot legs remain an issue even if you're not popping them . He also goes into a reason I completely overlooked on reasons for building low on a high-wattage mod - given the maximum voltage output you're not going to be able to deliver enough power on a high-resistance build to reach the full wattage potential.
 

kickboxerwalker

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the science can be tough but it all comes down to preference. the higher the resistance, the more voltage the mod has to provide to to heat the coil and provide a good vapor. by building with lower ohms, it decreases the voltage demand and allows the current to fine tune the rampup time, heat of the vape, cloud and flavor production. for these reasons, alot of people find that they have more options with sub-ohming rather than going above 1 ohm. again, it all comes down to preference. some basics are that bigger wire can handle more power but takes longer to heat up (rampup time), smaller wires are more limited in power ranges, but have less ramp up time and can produce more heat. so if you like a certain amount of heat and vapor, it may be easier to achieve and fine tune with lower resistance but its a balance. too low ohms can be just as difficult to fine time as too high ohms. if ohms are too low, you might not get it to heat up right even at high watts. high ohms can go too hot to too cool with small changes and limit the amount of vapor and flavor. scortching the ejuice is easier to do at high ohms too.it really comes down to preference. i like between .2-.5 for my RDA but .5-1.2 for my tank. different build for different attys. play with it. you may find you like a few different builds at different ohms.
 

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