Help me understand how power affects the vape experience

[Dave2603]

I'm having a little trouble understanding what ultimately affects the vape experience. What I mean is... on a regulated device, like the istick 50W, is there any difference between using a .5 ohm coil in my Subtank Mini, and regulating the wattage to 20W vs using a 1.2 ohm coil in the same tank and regulating the wattage to 20 watts? I realize that by increasing the resistance of the coil, my voltage has to go up to achieve the same wattage, and my amp draw goes down, but with the wattage being the same, will the volume, density and temperature of the vapor be equal?

 

[AndriaD]

No; the .5Ω coil will be hotter; with sufficient airflow, that will mean bigger clouds; with insufficient airflow, that will mean dry, burnt hits.

Andria

 

[niczgreat]

Hi Dave,
It's a great question.
Everyone has their preference. Some prefer Higher Ohms at Higher Voltage and others prefer lower Ohms with Higher Watts.
No right or wrong just preference.

I'm not familiar with the Subtank Mini. I see that you can buy premade coils or do your own.

I"ve been vaping on a Reo Gran lp, Reomizer 2 at .24 Ohm at around 50 watts or so but it's a not a mini RBA. 20 Watts for me would be anemic.
I'm currently on a New VV Bottom Feeder that just came out called a GreyScanno 50 and it's using it's own RBA
bigger then the Reomizer 2. I've built it to .64 Ohms and I had to dial it down to 40 Watts.

There are too many factors that come into play. The major one is the airflow. The stock tanks generally have very little surface area and aeration and
will tend to run hotter.

The one difference you should see is that the 1.2 Build assuming it uses Higher Gauge Wire will heat up more quickly.

Also how much surface area of the wick is coming into contact with the coils. .50 at 20 watts is not very high in terms of wattage and heat but I'm assuming that
because this is a mini that it has limited surface area so you may not be able to go higher.

Tell us how it goes. The fun is in experimenting!

 

[Dave2603]

Thank you. It makes sense that higher temps would lead to vaporizing more juice. So I assume that the higher resistance coil would require a higher wattage setting to achieve the same temperature as the lower resistance coil at a lower wattage setting (assuming the wicking and airflow were adequate for both)?

 

[zoiDman]

I'm having a little trouble understanding what ultimately affects the vape experience. What I mean is... on a regulated device, like the iStick 50W, is there any difference between using a .5 ohm coil in my Subtank Mini, and regulating the wattage to 20W vs using a 1.2 ohm coil in the same tank and regulating the wattage to 20 watts? I realize that by increasing the resistance of the coil, my voltage has to go up to achieve the same wattage, and my amp draw goes down, but with the wattage being the same, will the volume, density and temperature of the vapor be equal?

There isn't really a Good Answer to your question. Because it Depends if you use the Same Wire Gauge.

If you use the Same Sire wire gauge, then the .5 Ohm is going to be Hotter. Much Hotter.

But look what happens if you use a Different Wire Gauge ...

24ga @ .50 Ohm / 20W = 177 Heat Flux.

27ga @ 1.2 Ohm / 20W = 209 Heat Flux.

Coil wrapping | Steam Engine | free vaping calculators

So in the above case, the 1.20 Ohms is going to be Hotter than the .5 Ohms.

 

[State O' Flux]

I'm having a little trouble understanding what ultimately affects the vape experience. What I mean is... on a regulated device, like the iStick 50W, is there any difference between using a .5 ohm coil in my Subtank Mini, and regulating the wattage to 20W vs using a 1.2 ohm coil in the same tank and regulating the wattage to 20 watts?

I'm not sure I understand using 20 watts for both net resistances? Is this a typo?

The 20 watt 0.5Ω build (using 28 gauge as a constant) will have a net coil surface area of 26.15 mm² and a heat flux of 710 mW/mm². This heat flux is well above a more typical HF of 200-300 mW/mm².

Either a thicker wire or lower wattage will reduce the heat flux into a more usable range... the more advantageous thicker wire option would also increase the net coil surface area. For example, 25 gauge wire, will reduce the heat flux to 250 mW/mm², and increase surface area to 77.11 mm².

By comparison, a 1.2Ω coil will have a greater net coil surface area of 65.58 mm², but a much lower heat flux of 296 mW/mm².

This comparison is a good example of why it's necessary for the build - meaning wire gauge and mass, net resistance, and wires, if more than one, in parallel - to be in balance with a complementary wattage.
Complimentary in the sense that one achieves vape characteristics, which are somewhat subjective in nature... of a user preferred heat flux value, and coil surface area sufficient to produce satisfactory vapor flavor and density, for the juice blend used.

With the included sample Steam Engine links, I hope that I've explained this adequately... if not, you may want to read my blogs on the above variables, for a more in depth understanding.

 

[edyle]

I'm having a little trouble understanding what ultimately affects the vape experience. What I mean is... on a regulated device, like the iStick 50W, is there any difference between using a .5 ohm coil in my Subtank Mini, and regulating the wattage to 20W vs using a 1.2 ohm coil in the same tank and regulating the wattage to 20 watts? I realize that by increasing the resistance of the coil, my voltage has to go up to achieve the same wattage, and my amp draw goes down, but with the wattage being the same, will the volume, density and temperature of the vapor be equal?

different coils will run at different power.
depends on the gauge of wire, and whether single or dual coil.

in theory, 20 watts should evaporate a certain amount of juice
one case would be a hotter vape from a smaller spot
the other case would be a smoother vape from a wider surface area.

 

[niczgreat]

No; the .5Ω coil will be hotter; with sufficient airflow, that will mean bigger clouds; with insufficient airflow, that will mean dry, burnt hits.

Andria

I have to respectfully disagree.
The wattage remains the same. So assuming that his device works properly.

The .5 will be running at 3.1V
The 1.2 will running at 4.9V

The temperature should be close to the same.

Theoretically If all is equal then they should both be equally hot.

The variable is how much coil to wick surface that you have.

 

[edyle]

Thank you. It makes sense that higher temps would lead to vaporizing more juice. So I assume that the higher resistance coil would require a higher wattage setting to achieve the same temperature as the lower resistance coil at a lower wattage setting (assuming the wicking and airflow were adequate for both)?

That would be correct if the two coils are made of the same wire, and both are single coils.

 

[Dave2603]

Thank you all so much for your answers! This is such a great place, with so many folks who are so willing to share their knowledge. I know that it's difficult to give a simple answer to a question that has so many variables.

 

[zoiDman]

Thank you all so much for your answers! This is such a great place, with so many folks who are so willing to share their knowledge. I know that it's difficult to give a simple answer to a question that has so many variables.

I read something about a Year Ago that didn't seem to make sense until I started using Different Wire Gauges, Different Diams, and amount of Wraps.

And that is... "It Isn't about Watts. It's about Wicking, Air Flow and Wire Temperature."

I was kinda Stuck in a Coil Building rut. Only had one gauge of Kanthal A1. Figured I could Control everything with just Watts.

Then I got Kanger Subtank Mini and Couldn't get it to work right. I was about to give up on it and call the 998 People who said it great Liars. But how could All these People be Wrong? So I bought a Spool of 24g, 26g and 28g Kanthal A1 and started Playing around with Different Configurations.

I was Amazed how Different a Hit you can get by Using Different Gauge wire and Different Geometry of a Coil. And what I thought was the Most Important thing, Ohms, really Wasn't. It was Heat Flux. At least, for Me it is.

So I guess what trying to say is You probably will have to try a Few Different Configurations for a Coil to find what work Best for You and Your Hardware.

 

[Dave2603]

Thanks zoiDman. You've really hit on my situation. It makes sense to me that ultimately, what we are trying to do it transfer heat from the coil to as much juice as is needed to create the vapor that we find most enjoyable. I was trying to oversimplify it my mind by assuming that the two coils would perform the same assuming that the wattage was the same. I realize that coils that have different surface areas and different masses will produce vapor differently by transferring their heat to the juice differently.

 

[zoiDman]

Thanks zoiDman. You've really hit on my situation. It makes sense to me that ultimately, what we are trying to do it transfer heat from the coil to as much juice as is needed to create the vapor that we find most enjoyable. I was trying to oversimplify it my mind by assuming that the two coils would perform the same assuming that the wattage was the same. I realize that coils that have different surface areas and different masses will produce vapor differently by transferring their heat to the juice differently.

Yeah... There are Many Variables that go into what Makes a Hit a Hit.

BTW - I have been having Real Good Luck using 3.5mm Coils. And they are Much Easier to wick than 3mm or the 2.5mm Coils I used to build.

 

[Dave2603]

Right now, 95% of the time I am vaping a Subtank Mini, a Melo, or an Atlantis tank with pre-made coils and I enjoy them all. The Subtank is the only one of the three that has two different coils available for it. I also own a couple of RDA's and have built some very simple coils for them, but I haven't really experimented much with different types of coils.... but I'm sure I will in time!

 

[edyle]

Thanks zoiDman. You've really hit on my situation. It makes sense to me that ultimately, what we are trying to do it transfer heat from the coil to as much juice as is needed to create the vapor that we find most enjoyable. I was trying to oversimplify it my mind by assuming that the two coils would perform the same assuming that the wattage was the same. I realize that coils that have different surface areas and different masses will produce vapor differently by transferring their heat to the juice differently.

I think if you play around with the numbers using the steam engine calculator you will get a feel for it.

Kanthal A1
gauge ----- watt per ohm (per coil) for 200mW/mm2
34 ----- 1.4
32 ----- 3
30 ----- 6
28 ----- 10
26 ----- 23
24 ----- 45
22 ----- 91
20 ----- 182

Coil wrapping | Steam Engine | free vaping calculators

Current might be a more intuitive way of thinking about it.

gauge ----- current (Amps) for 200mW/mm2
34 ----- 1.2
32 ----- 1.7
30 ----- 2.4
28 ----- 3
26 ----- 5
24 ----- 7
22 ----- 10
20 ----- 13

 

[Dave2603]

Steam engine is fantastic! I have learned a lot doing just as you have suggested..... playing around with the numbers and seeing how things change as you change just one variable.

 

[edyle]

Steam engine is fantastic! I have learned a lot doing just as you have suggested..... playing around with the numbers and seeing how things change as you change just one variable.

Did you notice the wattage setting and see that when things are like 400 watts/mm2 it's RED and 50 watts/mm2 is BLUE, and you get GREEN around 200 watts/mm2 ? You input the watts value

 

[AndriaD]

Thank you all so much for your answers! This is such a great place, with so many folks who are so willing to share their knowledge. I know that it's difficult to give a simple answer to a question that has so many variables.

True; I always use 29ga wire for everything, so I think in those terms. It heats quite quickly, so two coils as you described, the lower resistance one would be hotter. When I dropped from 1.8Ω to 1.3Ω, I saw a visible difference in the amount of the vapor, and I needed to use a longer, angled driptip, it was so hot on my mouth.

Andria

 

[Dave2603]

Edyle - Yes, that's a great feature! I hadn't paid any attention to that particular part of the results, but I can see how useful that's going to be. Thank you.

 

[Dave2603]

I know what you mean about the temperature Andria. When I first started using the subohm tanks, the heat really bothered me. When I bought my first Kanger Subtank, I actually had to find a driptip that had a plastic insulator because the tip seemed to get much to hot to me. Within a fairly short amount of time, I found that I got used to it and it stopped bothering me.