Wire surface area calculator

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Caterpiller

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Occam's Razor:

Maybe the mod only needs 70 watts to get the coil up to 420 degrees?

Have you tried to see if it draws more watts at 450, 500 degrees, etc?

Absolutely right - if I turned the TC up to 550F it would chuck a lot more power into the coils.
 
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Caterpiller

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I'm not trying to start arguments or anything.

I legitimately want to help you determine what might be happening here.

I found the formula to determine how many watts are needed to heat steel to a given temperature.

Watts = 0.05 x Lbs of Steel x ΔT (in °F) / Heat-Up Time (in hrs)

The example here is for a .2 ohm build that we want to heat up to 420 degrees in one second.

.05 is the first number.

85mm of 22awg is about 220mg
A pound is 453592mg
Thus, 85mm of 22awg weighs .00048 pounds (220/45392)
.00048 is the second part.

Relative temperature increase to 420 from 70 is 350.
350 is the third part.

We will assume the third part is 1 seconds. This works out to .00027 hours.
.00027 is the fourth part.

Watts therefore = (.05 * .00048 * 350 / .00027)
That's = 31 watts.

This matches up with the coil calculator for a heat flux of 180.

Given the above - I don't think the mod is letting you exceed 70 watts. It simply does not need to use that much energy to get your coil to 420 degrees.

Here is the math for a .09 ohm build: .05 * .0002 * 350 / .00027
= 12.96 watts

LOL - please don't flame me!

;-)



View attachment 700681


It's not a mystery - IT'S THE AIRFLOW
 
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-KT-

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Yes you are missing the point, but don't worry you seem to be in good company.

With the watts set to 140watts and the TC set to 430F this build was teaching 430F in about half a second and TC was kicking in and reducing the watts to the 60w to 70w range - IF I HAD MORE AIRFLOW THE COILS WOULD COOL MORE EFFICIENTLY AND TC COULD DELIVER MORE POWER

When I use TC on my mod - it automatically varies the watts. Is it *starting out* at 140 and decreasing to 70? I think it's acting normally - the math shows that it does not require a lot of wattage to slowly (5 seconds) heat a coil to 420 degrees.

if you want to heat a coil fast, more wattage does matter.

But once the coil is hot - it simply isn't going to require a lot of wattage to keep it at that temperature. I think you are saying that if there is more air flow, your inhale would cool the coil such that the mod should be pumping 140 watts through the coil to match the cooling effect.

Take the cover off the RBA - put it in front of a very strong fan. Press the fire button on TC mode.

See if this has effects. That would be a way to test if it's an air flow issue.

Another way to look at is this:

You yourself already said that the taste was burnt at 120 watts. Why does it make sense to force your mod to run at 140 watts? 140 watts is much more than is required to get to 420 degrees, according to the math. Maybe 140 at the start - but 70 should easily sustain 420 degrees.

Even 35 watts will get to 420 degrees - it will just take a few more seconds.

Is power itself a good thing? If it doesn't taste like a good hit at 420, try 440 or 410.

"The place where the mind stops at one thing is called the abiding place."

-- Taken Soho
 

Asbestos4004

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Yes you are missing the point, but don't worry you seem to be in good company.

With the watts set to 140watts and the TC set to 430F this build was teaching 430F in about half a second and TC was kicking in and reducing the watts to the 60w to 70w range - IF I HAD MORE AIRFLOW THE COILS WOULD COOL MORE EFFICIENTLY AND TC COULD DELIVER MORE POWER
You can save the caps, dude. People are trying to help you out and you feel the need to get all edgy. If everyone is misunderstanding you, perhaps it was your poor explanation. Figure your own crap out. Sheesh.
 

Caterpiller

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When I use TC on my mod - it automatically varies the watts. Is it *starting out* at 140 and decreasing to 70? I think it's acting normally - the math shows that it does not require a lot of wattage to slowly (5 seconds) heat a coil to 420 degrees.

if you want to heat a coil fast, more wattage does matter.

But once the coil is hot - it simply isn't going to require a lot of wattage to keep it at that temperature. I think you are saying that if there is more air flow, your inhale would cool the coil such that the mod should be pumping 140 watts through the coil to match the cooling effect.

Take the cover off the RBA - put it in front of a very strong fan. Press the fire button on TC mode.

See if this has effects. That would be a way to test if it's an air flow issue.

Another way to look at is this:

You yourself already said that the taste was burnt at 120 watts. Why does it make sense to force your mod to run at 140 watts? 140 watts is much more than is required to get to 420 degrees, according to the math. Maybe 140 at the start - but 70 should easily sustain 420 degrees.

Even 35 watts will get to 420 degrees - it will just take a few more seconds.

Is power itself a good thing? If it doesn't taste like a good hit at 420, try 440 or 410.

"The place where the mind stops at one thing is called the abiding place."

-- Taken Soho

I know how TC mode works - I tried to get a little more vapor production by trying the 22g coils - it's TC mode so I don't expect it to reach my max power setting, but the coil mass increase from 24g to 22g meant the coil was staying to hot - the power was not being applied - and I didn't have enough airflow to cool the 22g.

So I very happily went back to the 24g which is working wonderful
 
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Zakillah

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If you want your vape to be cooler and less power hungry, just dont use 22G.
The thinner the wire, the cooler your vape will be. If you make the Coil the same size (more wraps with thinner wire) you wont even loose surface area. Thick wire equaIing big surface area equaling huge clouds is a persitant misconception.
 

mcclintock

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    Yes you are missing the point, but don't worry you seem to be in good company.

    With the watts set to 140watts and the TC set to 430F this build was teaching 430F in about half a second and TC was kicking in and reducing the watts to the 60w to 70w range - IF I HAD MORE AIRFLOW THE COILS WOULD COOL MORE EFFICIENTLY AND TC COULD DELIVER MORE POWER
    As long as 140 W actually happens for a moment the mod is working correctly -- how fast it hits TC pretty well confirms it is. If TC (or other) immediately cut it to 60-70 it wouldn't protect rapidly. I expect the vape is better with it set properly, as well.

    My experience agrees that the atty, airflow etc. can create a fixed limit that bigger coils don't really affect. That's the way it works, air, coils size etc. produce individual limits, but what I've seen is even more precise than that: A particular atty, airflow setting, drip tip and YOU could end up wanting the exact same power with almost any coil. Also there's something in "if I had more airflow" -- that's probably the highest you'll be comfortable with.
     
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    stols001

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    Well, that may be true but you are already at 140 watts, how much more power do you think you need?

    Airflow is certainly a part of the equation, but I think you do reach outer limits of whatever adjustment you make and vaping at the watts and temps that you are.... I'm not sure exactly what you are going to do to your airflow to make it better... I guess you could take your airflow ring off and just drill giant holes into it and etc.

    This is a bit tongue in cheek but I do think that increasing your airflow might help... slightly. How much, I am not sure.

    Are you used to vaping at higher wattages?

    Anna
     
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    Asbestos4004

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    The whole discussion is rather pointless. It's not a TC issue. It's an atty issue. Certain attys are designed for certain builds. If I throw a .1 ohm build in a igo w, I'll suffer. The same build in a goon would likely be spectacular. It seems the op has figured out that he needs to build within the limitations of his atty.

    Fun observation: it seems like 80%+ of the threads revolving around poor performance are rooted in the math and the numbers rather than the results. Folks are getting wrapped up in why they can't run a device at 140w rather than just setting it where it delivers a satisfying vape. I don't want a scientifically perfect vape .... I just want a good one.
     

    Caterpiller

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    @Asbestos4004

    That's all I was trying to say for the second half of this thread - I probably didn't explain myself as succinctly as you just did, but I quickly realised that 22g wasn't going to do it with the airflow available in the DotMod - and I was very happy to go back to the 24g build - because it's a better vape - I wasn't looking for a way to make the 22g work just saying it was interesting that it didn't.

    .. the CAPS were tongue in check, but I see how they may not have come off well - my bad.
     

    DaveP

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    The article below may be helpful to the OP. Most mods don't adjust the power, although some new ones do. They only pulse and control the on time of the coil to maintain temperature. If your wattage is set too high, then it will not control the vape heat as closely as it will if your wattage setting is close to what's needed to provide the right temp for your coil and air flow. You choose the power setting that provides the TC vape that suits your vaping style and the air flow of your mod. The mod then controls the temp by pulsing the coil. Finding the sweet spot for power is key to a good TC vape.

    Temperature Control – A Vaping Revolution
    Every TC mod provides a temperature setting: rather than only setting the power (watts) of the vape, you also set a target temperature. The mod then automatically adjusts the power as you vape. Keeping your coil – and therefore your vape – at or very near your chosen temperature. The wattage you set is therefore only a maximum wattage, and some new TC mods don’t even have a power setting; the mod will always use as much of its full range of power as is needed to reach and maintain temperature.

    Common vaping temperatures are in the range 200°C- 250°C / 392°F – 480°F, with the temperature usually set in increments of 5°C or 10°F.
     
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    -KT-

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    The whole discussion is rather pointless. It's not a TC issue. It's an atty issue. Certain attys are designed for certain builds. If I throw a .1 ohm build in a igo w, I'll suffer. The same build in a goon would likely be spectacular. It seems the op has figured out that he needs to build within the limitations of his atty.

    Fun observation: it seems like 80%+ of the threads revolving around poor performance are rooted in the math and the numbers rather than the results. Folks are getting wrapped up in why they can't run a device at 140w rather than just setting it where it delivers a satisfying vape. I don't want a scientifically perfect vape .... I just want a good one.
    Agreed. The science might explain *why* something is not producing a good vape.

    But the bottom line is "a good vape."

    As I write this I am vaping at 25.5 watts on an .85 ohm Clapton. It's a nice cool vape and science explains why. But science itself isn't the same as a good vape.



    Sent from my R1 HD using Tapatalk
     

    DaveP

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    As I write this I am vaping at 25.5 watts on an .85 ohm Clapton. It's a nice cool vape and science explains why. But science itself isn't the same as a good vape.

    Agreed. I'm vaping at 13 watts on a .77 ohm SS316L expanded single coil in power mode. It vapes just as well in TC mode producing about 360F (at 10W) under a 400F TC setting. Whatever works for your mod and atomizer (and vaping style) is the right setting.
     

    -KT-

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    Agreed. I'm vaping at 13 watts on a .77 ohm SS316L expanded single coil in power mode. It vapes just as well in TC mode producing about 360F (at 10W) under a 400F TC setting. Whatever works for your mod and atomizer (and vaping style) is the right setting.

    Agreed.

    I'm totally new to all this stuff - but I am not afraid to experiment.

    I have done builds that vape nice at 100 watts. And others that vape nice at 25.

    But when I do these things - I understand *why* things happen. That was all I was trying to get to here. I wanted to know *why* things were happening.

    Once I know why things happen, then it's easier to set up an informal experiment to test concepts. I do all this because I really like to vape. I like a good experience, and if I have to learn some science to get a good experience, I will do it.

    That doesn't just apply to vaping. When I was modifying cars, I knew exactly WHY I was changing carbs or cams, etc. . . I wasn't doing it so I could say "I have a Holley Double Pumper." I was doing it to perfect the amount of air/fuel going into the intake manifold.

    It's about understanding. And being able to "not know." I know that I do not know. But I also know what I know, LOL.

    For example, if I was hitting a limit on watts - and I thought it was related to airflow - I would just take off the drip tip. That is because drip tips reduce air flow. That is why attys went from 510 to 810, and it appears that some cloud chasers don't even use them in competition. I am not a cloud chaser - but since I know that cloud chasing is about "air" - I filed that fact away for future use.

    If TC-controlled watts increase without a drip tip - even just slightly - then it would prove that air is an issue in the above case.

    But above, after I did the math - I learned that it just doesn't take a lot of watts to heat 1/10 of a gram of steel to a few hundred degrees. Interestingly - this concept of wattage is different than what we think about in ohms law. In ohms law - we are looking at the maximum current that will run through a circuit at a given ohm rating (given amps/volts/or watts as the second value).

    When we look at the amount of watts it takes to heat something - we are looking instead at literally the amount of (joules) energy. That is why watts can be converted to horsepower, for example. As an aside - 140 watts is nearly 1/5 horsepower.

    Opinions are like elbows, everybody has one. So the above is mine. I could also be totally wrong on the science - but again - theory is tested by experiment.

    My other elbow is that if someone posts a question in a public forum - they should be prepared to get answers. They may not like the answers. But courtesy dictates politeness.

    KT
     
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    DaveP

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    If TC-controlled watts increase without a drip tip - even just slightly - then it would prove that air is an issue in the above case.

    But above, after I did the math - I learned that it just doesn't take a lot of watts to heat 1/10 of a gram of steel to a few hundred degrees. Interestingly - this concept of wattage is different than what we think about in ohms law. In ohms law - we are looking at the maximum current that will run through a circuit at a given ohm rating (given amps/volts/or watts as the second value).

    When we look at the amount of watts it takes to heat something - we are looking instead at literally the amount of (joules) energy. That is why watts can be converted to horsepower, for example. As an aside - 140 watts is nearly 1/5 horsepower.

    It's all a series of trade-offs in vaping. More heat needs more airflow to keep the vape at the right temperature. Larger coils consume more wattage to produce more heat. Atomizer designs can up the efficiency of the process and create more flavor.

    It is surprising that vaping can be satisfying at 10W or 200W if the hardware is designed to accommodate the variations. Most of us old-timers started vaping to quit smoking. We wanted something that replicated our cigarette. Eventually, people who had ever smoked thought it was cool to blow clouds with a mech and a dripper, and starting playing around with atomizers to perfect the DTL style.
     

    Eskie

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    It's all a series of trade-offs in vaping. More heat needs more airflow to keep the vape at the right temperature. Larger coils consume more wattage to produce more heat. Atomizer designs can up the efficiency of the process and create more flavor.

    It is surprising that vaping can be satisfying at 10W or 200W if the hardware is designed to accommodate the variations. Most of us old-timers started vaping to quit smoking. We wanted something that replicated our cigarette. Eventually, people who had ever smoked thought it was cool to blow clouds with a mech and a dripper, and starting playing around with atomizers to perfect the DTL style.

    While it might be a matter of semantics, but rather than view things as trade offs, I view them as variables. I'm free to play around with those variables and balance them until I have the vape I like. The set of variables may be interdependent and that configuration for tank x may not be at all applicable to use with tank y.
     

    DaveP

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    While it might be a matter of semantics, but rather than view things as trade offs, I view them as variables. I'm free to play around with those variables and balance them until I have the vape I like. The set of variables may be interdependent and that configuration for tank x may not be at all applicable to use with tank y.

    Same here, but I rely on Steam Engine to verify coil designs from time to time. I agree that what's good for one tank may not be right for another. I tend to play around with coils to find the right diameter, # turns, wire gauge, ramp time, and distance over the air port until I feel like I've hit the sweet spot.

    That's probably why i keep coming back to the old faithful Kayfun V2 for MTL. :) Too many tanks try to be everything to everyone and don't really work well through the range of airflow and juice atomization at a given power level.
     
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