Watts do not matter. Its all about wire temp. Read on

[bilboda]

Random measurements I've picked up along the way, you'll have to break out your calculator.
28 AWG
(Ohms/ft. @ room temp): 5.27
32 gauge Kanthal A resistance wire
Resistance- 13.81 ohm/ft 45.3 ohm/m.
Wire Diameter- 0.008" / 0.20 mm.
34 gauge Kanthal A-1 resistance wire
Resistance- 21.28 ohm/ft 69.80ohm/m
Wire Diameter- 0.0063" / 0.16 mm

 

[gdeal]

bilboda - not sure what you are stating or questioning in your post. Any clarification?

Random measurements I've picked up along the way, you'll have to break out your calculator.
28 AWG
(Ohms/ft. @ room temp): 5.27
32 gauge Kanthal A resistance wire
Resistance- 13.81 ohm/ft 45.3 ohm/m.
Wire Diameter- 0.008" / 0.20 mm.
34 gauge Kanthal A-1 resistance wire
Resistance- 21.28 ohm/ft 69.80ohm/m
Wire Diameter- 0.0063" / 0.16 mm

 

[bilboda]

It speaks for itself. A fellow asked how many coils to get 1.5 ohms. You can measure out the length and then wrap it around your wick, however thick the wick is and you'll be at or close to your 1.5 ohm coil
example 28 ga
12 inches = 5.27 ohms so 5.27x = 1.5*12 x= wire length for 1.5 ohms.
x= 3.41 inches and so on. Just cut that length and wrap
I might add that a chart from pelican wire says 5.4927 ohm/ft Kanthal A-1 872 ohm Alloy | Pelican Wire
You could always take a multimeter to your wire and measure out 1.5 ohms as well adding a little length for wrapping around the posts.

 

[BlkWolfMidnight]

Also one thing to consier is the operating load on your equipment. I understand that with a lower gauge wire you will have 2 things in play, thicker guage (Larger surface for thermal conversion) and lower ohms. The real question is where is the bread and butter zone to reach optimal tempeature for vaporization within a reasonable time frame while staying within the required amperage load limitations of your battery.
As mentioned in a previous post, not all wire is created equil...obviously. The real issue comes is when you make contact with your battery and complete the circut. Really what happens at that point (yes we all know the coils glow).
Load is the required amperage to drive the system, the load will increase as the guage of the wire decreases. Though this may not seem like a big deal however you can have a 3.7v battery with little amperage left and the result would be a coil system that wouldn't work...as soon as you make contact the battery will drop below operating levels (and safe levels at that).
I've played with 28 guage wire before, the operating load on a 8 wrap 1.8 ohm coil would drop my battery from 4.03 v to around 3.6v. This is what voltage your really vaping at, not what your battery reads at stand still. All batterys will have a residual charge at standing, this gets in to recovery rate which is another topic all together.
30 guage wire will only drop the battery on load at .20 v at operating functionaly, I loose about 3.5 wraps however if spaced out evenly I find that the thermal zone is better then covered without any issues (You can see this by dry burning and watching which spots on your wick glow red, if it glows evenly then your good to go). Atomization dosen't require high heat, it requires the right mixture of heat and liquid, two systems that must work in unicen, you can have an awesome coil system and slow go feed will result in burnt juice no matter the watts of heat or ohm's of your coil.
Just my thoughts on the process and what I've learned the many nights of dry burning with volt meter...

 

[rotohammer]

For me watts matter, as in what setup gives me a good volume of vapor with clean taste with the least amount of watts. For me right now its a 2ohm 10 wrap coil 32ga NiCr wrapped around a 18ga needle (1.25mm) with a 1mm diameter SS wick at 5.5-6.0 watts.

Lower watts = longer battery life. Thinner wick = less metal/liquid mass to heat up on each draw.

 

[gdeal]

For me watts matter, as in what setup gives me a good volume of vapor with clean taste with the least amount of watts. For me right now its a 2ohm 10 wrap coil 32ga NiCr wrapped around a 18ga needle (1.25mm) with a 1mm diameter SS wick at 5.5-6.0 watts.

Lower watts = longer battery life. Thinner wick = less metal/liquid mass to heat up on each draw.

Hmm... I cant disagree with your concept; that lower watts = longer battery life. And that a thinner wick = less heat sink, so the power applied is more efficient and that if I had my preference, I would go for efficiency or the lowest possible energy requirement.

But I think you are missing the point about wire temp and how you are communicating what works for you. Different gauge wire and differing amp levels gives very different wire temps. That wire temp will effect your vape. Total rate of energy transfer (watts) is different than the specific wire temp on mesh and how ejuice is vaporized at the wire level. That is what is described in the OP.

But put that aside for the moment. How are getting a wick to effectively work at only 1mm thick? Also, In dependent of your super wick, I also do not see how you are getting the resistance for the coil you described. For Nichrome, a 10 wrap coil at 1.25mm coil diameter calculates to either 1.6 ohms for Nichrome 60 or or 1.4 ohms for Nichrome 80 (PV Web Apps)

Watts do not matter. Its all about wire temp. (and add that longer explanation provided earlier too....) IMO

 

[Stephenst4470]

BJ, let me tap your scientific mind for a sec. Let me know if my logic is off, but wouldn't wire temperature, in a device that is properly wicked of course, pretty much be restricted to the vaporization point of the PG/VG mixture? Much as something submerged in a pot of boiling water would be restricted to @212F, regardless of the amount of heat applied to the pot? It seems like the PG/VG should stabilize the wire temp at the vaporization point of the fluid, with only the amount of vapor produced changing.

 

[BJ43]

BJ, let me tap your scientific mind for a sec. Let me know if my logic is off, but wouldn't wire temperature, in a device that is properly wicked of course, pretty much be restricted to the vaporization point of the PG/VG mixture? Much as something submerged in a pot of boiling water would be restricted to @212F, regardless of the amount of heat applied to the pot? It seems like the PG/VG should stabilize the wire temp at the vaporization point of the fluid, with only the amount of vapor produced changing.

There is much more. The water stays at 212F but it does not stabilize the burner, it can go to much higher temp and the water just vaporizes faster. Our juices are not water and have many ingredients that will burn and no matter how much juice is on the coil it will continue to get hotter depending on the power put to it. Our juices will catch fire and maintain a flame. So they not only have a vaporization point but also a flash point. Burning juices give off terrible fumes, probably unhealthy besides bad flavor. I have a suspicion most of the extreme LR vapers are on the boarder line of burning on those coils with minimum wraps reducing the heating area and concentrating high watts on a very small area.

 

[motelgrim]

I know this will be a bit off-point but air resistance plays a *huge* part in vapor production. Rather, air *flow*. I use an AGA-T Drilled to 1/16" This is a large hole, relatively. I wrap a 2/3 Kanthal 28awg 1ohm coil as a matter of course. With that much vapor production, my draw becomes *much* tighter. So much so, that if I crack my lips around the drip tip, I'll draw in air.
I bring this up because I tend to try things that I read about for myself. I'm going to wrap a 1.8ohm coil, see how many wraps that gets me at 28awg (because I hate math) and see how I like it but I *know* I'm going to pull *way* too much air because the 1/16" hole simply is too large. I'll fill my lungs up with more air than vapor by the time the coil gets up to speed.
There's a balance somewhere, and it's a per-person measurement. A Balance of vapor production (wire temp + air flow and vector) and the rate of which you prefer that vapor to enter your body.

This AGA-T setup is almost dependent on the vapor that my 1ohm coil produces to tighten up that draw and deliver me a vape that I deem satisfactory.

Food for thought.

BTW, does anyone know what, say, a standard Boge, 2 ohm carto has in it gauge-wise and number of wraps wise?
I always felt that cartos were extremely efficient from a power to vapor standpoint.

 

[gdeal]

I know this will be a bit off-point but air resistance plays a *huge* part in vapor production. Rather, air *flow*. I use an AGA-T Drilled to 1/16" This is a large hole, relatively. I wrap a 2/3 Kanthal 28awg 1ohm coil as a matter of course. With that much vapor production, my draw becomes *much* tighter. So much so, that if I crack my lips around the drip tip, I'll draw in air.
I bring this up because I tend to try things that I read about for myself. I'm going to wrap a 1.8ohm coil, see how many wraps that gets me at 28awg (because I hate math) and see how I like it but I *know* I'm going to pull *way* too much air because the 1/16" hole simply is too large. I'll fill my lungs up with more air than vapor by the time the coil gets up to speed.
There's a balance somewhere, and it's a per-person measurement. A Balance of vapor production (wire temp + air flow and vector) and the rate of which you prefer that vapor to enter your body.

This AGA-T setup is almost dependent on the vapor that my 1ohm coil produces to tighten up that draw and deliver me a vape that I deem satisfactory.

Food for thought.

BTW, does anyone know what, say, a standard Boge, 2 ohm carto has in it gauge-wise and number of wraps wise?
I always felt that cartos were extremely efficient from a power to vapor standpoint.

Sorta OT, but I''ll bring it back on topic. There are a lot of variables that can effect your vape experience and everybody is different. You are still talking about wire temp though.

The amount of airflow over your coils will effect your wire temp in addition to creating vapor production. Sounds like you prefer quick power hits, so a larger hole with higher power will work better for you than if you take longer slower pulls on the same set up. The high volume of air over your coils will counter the increase in watt density to maintain a lower wire temp so you dont burn your juice. Or you could turn you power down so that when you do take slower draws you maintain a similar wire temp.

Not sure what gauge wire boges use, but it is fairly thin...34g? That why you can get instant on with a pen type battery. There are efficient in power consumption and vapor production, but I dont really think you can get the same thick vapor density as you get with a lower gauge wire with the same resistance. IMO

Edit: BTW - Check out: PV Web Apps

Tomcatt set up a web page that does all the math for you......

 

[EDO]

Gdeal...a question for you. How come when I vape around 15 watts with 28g wire (1.0 ohms) the vape is smooth as silk but if I set my Vamo to 15 watts and try to vape with 32g wire (2.0 ohms)....it is harsh as hell? I don't even think the wattage really reaches 15 anyways but it is still much harsher than the low ohm set up with a mechanical mod.

 

[gdeal]

Gdeal...a question for you. How come when I vape around 15 watts with 28g wire (1.0 ohms) the vape is smooth as silk but if I set my Vamo to 15 watts and try to vape with 32g wire (2.0 ohms)....it is harsh as hell? I don't even think the wattage really reaches 15 anyways but it is still much harsher than the low ohm set up with a mechanical mod.

Three words..."wire surface area". 28g is ~58% thicker than 32g.

I dont have Kanthal wire temp calcs, but for Nichrome your example calcs out to 32g having a temp ~150 degrees hotter (12% more) than 28g in a static air environment. If you factor in airflow over the coil surface area on the outside of the coils and juice cooling/ss mesh thermal transfer to the wick on the inner side of the coils, its probably more of a difference than the 150 degrees.

Edit: Degrees are in celsius.

 

[EDO]

Makes sense....thanks.

 

[Stephenst4470]

I think 15 watts on 2 ohms of 32 is seriously burning your juice, turn down the Vamo and it should smooth out. If you have a big enough Genesis with a tall enough wick you can also run a 9 or 10 wrap 28 g on the Vamo that will vape beautifully at about 12 watts. It will come out to 1.6 or 1.7 ohms. That's the coil I usually run on an AGA-T+ on my Vamo. That's on an 80mm #500 wick.

 

[Stephenst4470]

Your Vamo will do 15 watts (or very close) as long as you are running stacked 350's, if you are running 1 650 then it peaks out about 12 watts.

 

[EDO]

Stephen...it was a conceptual question really....running a 32g wire at 15 watts is way too hot for me. I usually vape at 8-9 watts. That is the reason that I didn't try the 28g wire for the longest time. I figured it would be way too hot/harsh as well but it vapes like a dream at 15 watts on a mechanical mod.

 

[WillyB]

Stephen...it was a conceptual question really....running a 32g wire at 15 watts is way too hot for me. I usually vape at 8-9 watts. That is the reason that I didn't try the 28g wire for the longest time. I figured it would be way too hot/harsh as well but it vapes like a dream at 15 watts on a mechanical mod.

Did you actually do a loaded volts test to determine your 15W?

 

[flow.professor]

also, I think dual wick, single coil is the future

dual wick, single coil? how's that work?

 

[Skepticide]

This is the most impressive vape science thread in existence. Cheers! To add to the pursuit of the ultimate vape:

gdeal, I'd like to hear your thoughts on pressure. It is my understanding that because vapor is not a gas but a liquid in a gaseous state, it can be compressed back into liquid by pressure alone without cooling. If this is correct, then might that be the key factor in producing thicker vapor? And in the current model doesn't the draw create a slight drop in pressure inside the plant? The draw imparts vacuum force and encounters resistance at the air inlet.

Pardon my amateurish science, trying to close some enormous rifts in my understanding.

 

[cadcoke5]

It is my understanding that because vapor is not a gas but a liquid in a gaseous state,

You have misunderstood some of the terminology. A vapor is made of small liquid droplets suspended in air. Also note that most people misuse the word steam. True steam is an invisible gas. People often use the word steam to refer to the cloud of vapor that forms above a boiling pan. But that is not the correct usage. The vapor cloud is what is left after the steam cools and turns back into liquid droplets.

The exact process of how these droplets form in an atomizer is the current discussion. Here is my own current theory;

On the coil, the water in the e-cig juice turns into a gas (i.e. steam), and as it converts into a gas, it carries with it some of the glycerine and other stuff in the juice. Note that water, when vaporized, occupies about 1,000 times the original space. So, in essence, it explodes. The tiny droplets of liquid left behind in the air after the water "explodes" become the vapor particles. The water also cools and condenses into tiny droplets as well, but I don't think this is the main part of the vapor.

Where I get this idea from, is when I learned how an old-fashioned "cracker" works. This is a type of theatrical hazer. It puts out a long-lasting, thin fog, so that light beams will show up in a concert. It works by blowing bubbles through mineral oil. As the bubbles burst on the surface, it leaves behind tiny droplets of oil. These droplets are blown out of the device by a fan, to become the haze in the theater.

To test my theory, I first imagined it may be possible to separate the condensed water droplets from the other kinds of droplets that form the vapor. However, I suspect that when the water steam condenses, it will tend to condense back onto the other droplets, since steam tends to want a "seed" to condense onto.


Joe Dunfee