# Scientific or not



## Lushen (27/4/16)

Hi All

I doubt there is a calculator for this or a scientific calculation. Can somebody please give me advise:

How can I calculate my lowest resistance build to last me a specific amount of juice?

I have BF mechanical mods and I want a battery to last me the 7ml of juice.

I'm lazy and I'm also prepping for the out and about scenarios.


----------



## YeOldeOke (27/4/16)

Where's me popcorn.

Reactions: Like 1


----------



## DaveH (27/4/16)

The easiest way would be to do it empirically.
You have a specific resistance build now and you can see how much juice is used on one battery charge. Take it from there.
It will be a bit "hit and miss" nevertheless perhaps the best way.
Dave


----------



## Clouds4Days (27/4/16)

I'm by no means a guru on this matter at all but the way I see it is. The less ramp time the longer your batteries will last. So I think the lower the resistance the better? Or am I just talking kak? Hahaha

Reactions: Like 1 | Funny 1


----------



## DoubleD (27/4/16)

I use a single 1Ω coil using 28ga kanthal and get 6ml's of juice comfortably using one battery

Reactions: Agree 1


----------



## stevie g (27/4/16)

Dual coil here will get 6-8ml before battery swap.

Reactions: Like 1


----------



## Silver (27/4/16)

Hi @Lushen 

The thing is I have observed that when you go lower ohms, you get less life of the battery but you burn up more juice, so it sort of evens out for me from a juice volume perspective. Time wise, the higher ohm/lower power is way better

I dont know how to get 7ml, because I am only getting about 3ml (maybe 4ml) of decent vape on one 18650 batt. I can get to 6ml but the last 2ml is not as satisfying, power wise.

I think for longevity without battery changes, one really needs a dual battery mod

Reactions: Like 1 | Agree 1


----------



## Lushen (27/4/16)

Some interesting responses already, thanks guys.

@DoubleD I'm liking your suggestion

@Sprint what build and wire do you use on a single 18650?

@Silver this might be my reason for getting a dually from TMod 

@DaveH I was trying that method for a few weeks now but I have given up. It's just taking too long. I'm lazy and impatient

Reactions: Like 2


----------



## Lushen (27/4/16)

Btw, so far I have gotten the following results

Dual kanthal build of 0.45ohms get me through 4ml of juice before the battery starts to drain.

A single kanthal coil of 0,6ohms got me through 5.5 mls of juice 

This week I'm am trying single SS coils around 0.65ohms.

Reactions: Like 2


----------



## stevie g (27/4/16)

Parallel kanthal 28g 2.5mm dia. 

Used to use SS but it kept arcing my REO switch and creating carbon buildup.

Reactions: Like 1


----------



## Clouds4Days (27/4/16)

Lushen said:


> Some interesting responses already, thanks guys.
> 
> @DoubleD I'm liking your suggestion
> 
> ...



Hahaha I guess my response wasn't intresting. 
I tried...

Reactions: Funny 4


----------



## YeOldeOke (27/4/16)

Clouds4Days said:


> Hahaha I guess my response wasn't intresting.
> I tried...



I found it interesting. Brought a smile to my face.

Reactions: Thanks 1


----------



## DaveH (27/4/16)

Lushen said:


> Btw, so far I have gotten the following results
> 
> Dual kanthal build of 0.45ohms get me through 4ml of juice before the battery starts to drain.
> 
> ...



Well looking at those results I would 'guesstimate' a resistance of 0.75 - 0.8 ohms.

Remember though increasing the resistance (for a lot of guys) reduces the quality of the vape.
Dave

Reactions: Agree 1


----------



## Lushen (27/4/16)

Clouds4Days said:


> Hahaha I guess my response wasn't intresting.
> I tried...



No no no, I'm still thinking this one through. Sorry.

So, you are implying that the lower the resistance, <0.5ohm then the longer the battery lasts, right?

I thought lower resistance drains your battery quicker, or am I mistaken?

Or should I use 28gauge, but get a low resistance so that there is no ramp time?


----------



## DaveH (27/4/16)

Clouds4Days said:


> Hahaha I guess my response wasn't intresting.
> I tried...


No, it was interesting - unfortunately kak   
Dave

Reactions: Funny 1


----------



## Ezekiel (27/4/16)

Hi @Lushen

There's unfortunately too many variables - coil size vs airflow, wick size/material, juice composition (VG/PG/nic/flavour %'s), to estimate how quickly juice gets vaporized.

But as @DaveH suggested, you can do it empirically.

I guess you know about this tab from Steam Engine: http://www.steam-engine.org/batt.asp?b=Samsung_INR18650-30Q&mah=3000&c=5

Input your battery and play around with the resistance - you'll see a decent "Estimated number of puffs @ 5 seconds" window in the bottom right. I've found that that estimate is actually quite close. Anyway, I would suggest to first figure out how long your average puff time is. Mine is 3 seconds. Then take the estimated running time (from steam engine - lets say 15 min for a 3000 mah battery at 0.3 ohm, so in other words 900 seconds) and divide by your average puff time - in my case 900 sec / 3 sec = 300 puffs.

Then throw in exactly one ml in your bottle, and count how many ~3 second puffs it takes to finish 1 ml. That way you get an average puffs per millilitre. Lets say it took you 30 puffs to finish 1 ml.

Now you can just convert it back - 30 puffs / ml means ~ 210 puffs / 7 ml, which means you'll run out of juice before battery power. So in other words, in my case, I would need about 10 min running time to give me 200 puffs, which should be around 0.2 instead of 0.3 ohm. (Of course, changing the resistance will change the # of puffs per millilitre, so you'll have to run the 1 ml test everytime you try a new build)

Playing around with this (and writing it in a notebook) should get you to a pretty accurate and statistical value pretty quickly. But to get an estimate, just throw in the resistance of your current build into Steam engine, test how many puffs it takes to vape 1 milliltre, and measure your average puff time, and you'll get a very good ball-park guess.

Hope I made sense. At the very least, http://www.steam-engine.org/batt.asp should go a long way to give you a good starting ground.

Reactions: Like 4 | Winner 4


----------



## Lushen (27/4/16)

Ezekiel said:


> Hi @Lushen
> 
> There's unfortunately too many variables - coil size vs airflow, wick size/material, juice composition (VG/PG/nic/flavour %'s), to estimate how quickly juice gets vaporized.
> 
> ...



Thanks @Ezekiel

I guess I have a project over the next few weeks.
I'm definitely going to give this a try, even though I did not want to go through a whole process of calculations. I was just being a lazy vaper and trying to get a good estimated answer.


----------



## Ezekiel (27/4/16)

Lushen said:


> Thanks @Ezekiel
> 
> I guess I have a project over the next few weeks.
> I'm definitely going to give this a try, even though I did not want to go through a whole process of calculations. I was just being a lazy vaper and trying to get a good estimated answer.



Haha, sorry! I'm never satisfied with any suggestions from friends at first - I first try a bunch of different crazy things until I've messed everything up and confused myself, then I give a friend/online suggestion a try, and everything usually works perfectly then. Just my process I guess!

Reactions: Like 1


----------



## Lushen (27/4/16)

Ezekiel said:


> Haha, sorry! I'm never satisfied with any suggestions from friends at first - I first try a bunch of different crazy things until I've messed everything up and confused myself, then I give a friend/online suggestion a try, and everything usually works perfectly then. Just my process I guess!



Lol, I'm the same. 
And I'm just trying to find a good config for my BF's that make them low maintenance, so that I can be more lazy


----------



## Silver (28/4/16)

Hi @Lushen 

I hear you on the "low maintenance" part but for me, I would rather build the right coil to give me the most satisfying vape - irrespective of how much juice i get through on one batt. And then just take an extra batt and swop it out when its necessary. The extra hassle of swopping out a batt is a minor price to pay for a better vape throughout. But thats just me.

Am still interested to hear what setup you settle on to get you through 7ml on one 18650 batt. Might be a nice setup to reserve for one device...


----------



## Lushen (28/4/16)

Silver said:


> Hi @Lushen
> 
> I hear you on the "low maintenance" part but for me, I would rather build the right coil to give me the most satisfying vape - irrespective of how much juice i get through on one batt. And then just take an extra batt and swop it out when its necessary. The extra hassle of swopping out a batt is a minor price to pay for a better vape throughout. But thats just me.
> 
> Am still interested to hear what setup you settle on to get you through 7ml on one 18650 batt. Might be a nice setup to reserve for one device...


 
I agree @Silver, the quality of vape is the most important, regardless of maintenance. I do however want that one device that lasts me, one battery, one bottle.
This is for out and about's where it's just not practical to be carrying juice and batteries on me.

The closest I got on my Reo was 0.8 Ohm Kanthal build, 2.5mm ID. Got 6.5ml's of juice on one batt, but the last 0.5ml was not satisfying at all.
Running the Cyclone atty with one airhole open, and a Samsung Turd.


----------



## Christos (28/4/16)

@Lushen,
I use 7 wraps SS(316L)
2.5mm ID
single coil, roughtly 0.5 ohms.

After 1 reo bottle the voltage on 2900MAH batteries is 3,8V.
On blue smurfs which I think are 2000MAH the voltage is 3,65 - 3,7V.

Reactions: Like 1


----------



## Ernest (28/4/16)

Then maybe just my luck, because I like a 0.8 - 0.9 Ohm single 28g kanthal coil and always get a bottle per battery per day using a 2500MAH battery. On the one Reo that I have a slightly lower build I use a 3000MAH battery and get the same.

Reactions: Like 3


----------



## DoubleD (28/4/16)

Great thread


----------



## Lushen (28/4/16)

Ok, an update from testing today.

Reo and cyclone atty. Coiled with SS 26g 2.5mm ID 7 wraps at about 0.5 ohm and the battery lasted perfectly for a full bottle of juice with an LG turd.

Tomorrows testing is with Nichrome. I didn't really enjoy the sizzle and taste on SS today.

Reactions: Like 3 | Winner 1


----------



## Christos (28/4/16)

Lushen said:


> Ok, an update from testing today.
> 
> Reo and cyclone atty. Coiled with SS 26g 2.5mm ID 7 wraps at about 0.5 ohm and the battery lasted perfectly for a full bottle of juice with an LG turd.
> 
> Tomorrows testing is with Nichrome. I didn't really enjoy the sizzle and taste on SS today.


So chuffed my spec was replicated perfectly. This is science!

Reactions: Thanks 1


----------



## Christos (28/4/16)

Currently using a 1.7 ohm, 2.5mm ID ribbon kanthal single coil. 
At my calculations I'll be at 4v after 6ml


----------



## Lushen (29/4/16)

Christos said:


> Currently using a 1.7 ohm, 2.5mm ID ribbon kanthal single coil.
> At my calculations I'll be at 4v after 6ml



0.5 or 0.4 ribbon, and how many wraps?\
I am really keen to try it, as long as it gives me a nice warm vape.


----------



## Christos (29/4/16)

Lushen said:


> 0.5 or 0.4 ribbon, and how many wraps?\
> I am really keen to try it, as long as it gives me a nice warm vape.


6 or 7 wraps got me 1.7 ohms.
Not a warm vape at all I'm afraid.
I'll perhaps do a twisted ribbon kanthal when I get a moment and report back.

Reactions: Thanks 1


----------

