I would like to build a VVmod..

[kosliev]

I have some questions though, before I start, I hope this thread wont go ignored because its a wall
of text..

I've already made the choice on IMR batteries (3,7V), so I ask you first, with the abundance of LR atties, is there a point going higher voltage, if the watts (power) you vape at are the same?

example:

1.3ohm atty on 4V -> 3A current and a 12,3Watt vape
3.0ohm atty on 6V -> 2A current and a 12,0 Watt vape

The 1st one draws more current though, which probably means its gonna die much sooner?
But besides that, the wattage is the same, and so should be the vape.

Im asking this as a preface because if someone tried both (say a 801 at 5-6V and a 801LR at 3,7V) he could let me know, if the "feel" is the same, theres no point on going high voltage \ variable voltage when i can make do with 1 battery and a LR.

"you have to try things", yeah, I know, but I really hate having stuff sitting around i wont use..

Thanks for your time, *glances* damn i type too much

 

[asdaq]

That single batt at 3.7 will actually go from 4.2 to 2.7 (if you can stand it that low) which does get noticed with an LR, but the regulated/boosted setup will deliver stable voltage till the batts pack it in.

 

[CapeCAD]

Without switching/regulating you are not going to get consistent wattage across the full voltage range of your batteries. In addition, 12 Watts is a lot to be vaping with.

By using a higher voltage, then a switching converter or voltage regulator you can adjust the voltage down to maintain a more reasonable and consistent wattage across the entire battery life.

To use your example:
1.3ohm atty on freshly charged 4.2V -> 3.2A current and a 13.5Watt vape (Ouch!)
1.3ohm atty on nearly dead 2.75V -> 2.1A current and a 5.8Watt vape (Where's the vapor?)

 

[Java_Az]

I have some questions though, before I start, I hope this thread wont go ignored because its a wall
of text..

I've already made the choice on IMR batteries (3,7V), so I ask you first, with the abundance of LR atties, is there a point going higher voltage, if the watts (power) you vape at are the same?

example:

1.3ohm atty on 4V -> 3A current and a 12,3Watt vape
3.0ohm atty on 6V -> 2A current and a 12,0 Watt vape

The 1st one draws more current though, which probably means its gonna die much sooner?
But besides that, the wattage is the same, and so should be the vape.

Im asking this as a preface because if someone tried both (say a 801 at 5-6V and a 801LR at 3,7V) he could let me know, if the "feel" is the same, theres no point on going high voltage \ variable voltage when i can make do with 1 battery and a LR.

"you have to try things", yeah, I know, but I really hate having stuff sitting around i wont use..

Thanks for your time, *glances* damn i type too much

You pointed out why VV is awesome in your example

1.3ohm atty on 4V -> 3A current and a 12,3Watt vape
3.0ohm atty on 6V -> 2A current and a 12,0 Watt vape

No matter what ohm atomizer you slap on it your going to be able to dial the voltage to vaping perfection. So your not stuck looking for the perfect ohm atomizers for your PV. You can pick up whats on sale with no worries about not being able to adjusting them to the perfect wattage.

In my experience regular ohm'd atomizer last longer at a higher voltage then LR atomizers at a low or stock voltage. I got a 5 pack of 2.8 ohm atomizers 4 1/2 months ago and they are still going strong today. From day one they have been vaped @ 4.4 to 5 volts. Lr atties don't seem to last for me more then a month and a half. Thats on a JoyeTech Ego stock voltage

 

[kosliev]

Thanks for the replies!

Well yes, I already had in mind to specifically regulate it with a switching regulator, I dont know which yet (i've seen the PTR08100W, yes, but I'm afraid of the shipping costs), thats the logical next step.

I really just want to regulate the voltage so excess energy doesnt go wasted as heat (I'm already planning to stay around 5-6 volts), "get two 3v batteries", but you see.. I eyed those 18650 IMR 1600 mAh and they're just sexy or two IMR 16340, also a possibility ( I will not be using LiCoO2, even if protected, nor LiFePO4, because nor AW or Tenergy have a good enough discharge rate)(which if you're wondering are 700mAh and <550mAh respectively).

The fact i can use a pot to change the voltage is a welcome bonus for now.

After that, a few comparators or somethig to light up a led when the first cell goes under the nominal voltage so I know its time to recharge, take it as a "soft protection"


Voltage drop down besides, I'm really interested in if a vape feels the same with different devices that output the same wattage, I've heard so much good about 801LR that a single 18650 with one of those is tempting too.

Damn all the text I type

 

[jonboyusmc]

That's the beauty of VV. You can dial your juice into YOUR taste. I'm still fairly new to this, but I can tell you for sure, that not all juices are created equal. Each one is unique in and of itself. VV just allows you to find the "sweet spot" for every individual juice you choose to vape. A small box mod with a LM317 chip is really cheap to build, and great way to get your feet wet. That was my first VV mod, before making the evercool. It worked great, in a 1X2X3 project box from ratshack. I just didn't like the wasted battery life from the heat that the regulator used up. It would get so hot, you couldn't touch it.

 

[Gummy Bear]

And just to jump right in with nothing but my opinion.
You can dial in on a VV the exact same wattage that you would get with low voltage and LR atty and not have the same taste. I think the higher voltage tastes better. I have played with this first hand but remember that this is all just a matter of taste and what one guy likes someone else may not. Also for the most part (when space isn't an issue) a switching reg will give far better battery life than a booster chip will. (IMHO)

 

[CapeCAD]

Thanks for the replies!

Voltage drop down besides, I'm really interested in if a vape feels the same with different devices that output the same wattage, I've heard so much good about 801LR that a single 18650 with one of those is tempting too.

Damn all the text I type

Given the fact that the resistance is different, and the batteries are draining at different rates, I would guess that the time it takes to heat up would not be the same and there would be a difference in how the vape feels. I have not tried these differences myself, perhaps someone who has can add to this.

 

[Skyway]

With the flavors I have tried, I can not stand vaping at HV even if the wattage is around the same. Just something about HV it feels like it cooks the flavor too much. I have tried 6v with SR and HR attys and it is just not the same as 3.7v with LR. I have not killed one LR atty ever since Nov so I do not really see the whole thing about killing a LR sooner. On the same note, my friend is almost strictly 6v and he is killing attys all the time. Biggest thing I have noticed is how you treat your attys. You treat it good and keep it wet and don't take 7 second inhales and you should be good.

 

[kosliev]

Ah I see, so theres way too many variables to it.

Yes, a s.regulator will yield much better battery life than a booster, and as far as HV goes, my idea was around the 5V range, this is because whatever combo im at right now (m403/402) is just not enough warm vapor (0 nic too), the flava is ok.

Being that the power source is decided, I guess its time to find a good switching regulator, if i cant find anything reasonable, theres always TI free sample project.. PTR08100WVD.. shipping might be free to even europe countries so.. >_>!

Also, I guess i'll stick with a 801 atom for the time being, since its apparently one of the "heavyweights" for flavor (I lie, im just cheap like that and thanks to damulta i can make easy 801 connections )


btw skyway, LR atties can have their reistance changed greatly (temperature, juice, gunk), because the resistance is so low, while on regular ones (3 ohm +), its negligible, hence I dont think you tried the same wattage vape with different devices.
It could be your LR atty was almost a joye NR (1.8 ohms or there about), and your 6V HV vaping was with fresh stacked 3V batteries greatly overshooting 6V, and maybe you used a 510 NR which sits at a still very low 2.2 - 2.5 ohm resistance.

Again, I aknowledge that there is just too much variables in this talk. (unless you took readings while vaping )

m403/402 batteries are 3,7V too right? (no testers around here), i COULD take one apart and reuse the protection circuit, and connect it just to the first cell of the series (always the one discharging the lowest 1st), so it tells me whenever its under the nominal voltage (for the m403 li ion battery, should be similar of a IMR 3,7V, need to check), so it flashes and i know its time to put back those 2 batteries on the charger.
But then I need to keep in mind that.. that circuit surely tries to mess with the current output (pulsating current), .. so thats also probably a good idea, maybe if i had only one 3,7V cell.

well i could just use a small component with a few comparators in it, and check the V in the 1st battery and when its under a V i decide, a led lights up.

I swear I was never gifted with synthesis

 

[WillyB]

m403/402 batteries are 3,7V too right? (no testers around here),

No. The Smoore M401 batts come off the charger at about 3V, that's raw un-loaded volts.

 

[des09]

Some data points:

I vape with LR atties and carts, most around 2-2.5 ohm.
I have a buzz that is set at 4.30 volts, and I almost never adjust it, because it takes a screwdriver to do it. It has an unswitched variable regulator in it, and I sometimes notice the heat / wasted battery fromit, but it generally lasts me a half day or more on its 2 CR-123's, so I don't worry about it that much.

I also have a tekk mod that has a thumbwheel, and an evercool circuit. I generally adjust the wheel between the lowest setting (about 3.2v) and a 1/4 turn (4.5 volts) depending on the atty and juice. this monster lasts for days, I don't even know how long.

I used to have a roughstack... 3.7v fixed single 18350 battery. My personal impression was that I could tell when a battery was fresh, then very soon after that it settled into a consistent vape for most of the battery life, and then near the end of the charge it would sag dramatically if I didn't change bats before then.

I also have a riva, and some long 510 batteries that I use when I want to be discrete, or have nothing else charged, the long 510 batteries generally feel a bit weak, but tolerable, and the riva is pretty close to the roughstack was, maybe just a little bit weaker.

 

[Skyway]

I find that the ohm rating on the attys I get are pretty much right on with what my seller lists them at.
Low Resistance (1.6 - 1.8 ohms)
Standard Resistance (2.8 - 3.0 ohms)
High Resistance (3.9 - 4.1 ohms)
Mostly 801's and some 510's occasionally when using some smaller box mods. I find most 510's has too much wiking material near the bridge and a couple days of use start to taste a little funny. These are normally right around the following.
Low Resistance (1.5 - 1.7 ohms)
Standard Resistance (2.2 - 2.4 ohms)
High Resistance (3.1 - 3.3 ohms)
I have even tried a VV with all the different ranges of atty's and I find with dialing in the same wattage, it still isnt the same. I think the amperage has to do with some of the flavors and not just wattage. That is just me though. COuld be cRazY.

 

[kosliev]

WillyB, Wow.

Even with the best assumption of 3V on the load and a m40x atty at 2.5 ohm, I'm vapint at 3.6Watt.

Wow. I'm in disbelief. Its like I'm not even vaping.. jumping to 8-14 watts will probably be shocking.



des09, the evercool mod (switching regulator), is the best of the lot right?


edit for skyway

Yeah the whole watt thing baffles me too, I guess the geometry of atties and wicking and mesh material
greatly impact taste aswell, I have absolutely no idea about the current thing;

I mean on paper, you could have 2 devices giving the same wattage, but one runs 4A on the coil, the other just 1A, like this

4V / 1 ohm atty = 4Amp current * 4V = 16 watt vape
16V / 16 ohm atty = 1Amp current * 16V = 16 watt vape

of course these are extremes, but those two should have the same vape. but do they?

 

[Gummy Bear]

I have even tried a VV with all the different ranges of atty's and I find with dialing in the same wattage, it still isnt the same. I think the amperage has to do with some of the flavors and not just wattage. That is just me though. COuld be cRazY.

I agree,,, However with that said, I do wonder if the manufacturing process where a company makes the same model in several resistance not only change the length of the wire but also the coil diameter. A very small change in coil diam. will make a big change in the taste. I know this from the Genisis atty.

 

[WillyB]

... Standard Resistance (2.2 - 2.4 ohms)
High Resistance (3.1 - 3.3 ohms)
I have even tried a VV with all the different ranges of atty's and I find with dialing in the same wattage, it still isnt the same. I think the amperage has to do with some of the flavors and not just wattage. That is just me though. COuld be cRazY.

Well I've never had a Joye 510 come in at 2.4Ω in well over a year of use, the bulk of them come in at 2.1Ω, a few at 2.2Ω. But with inexpensive ohm meters, when you only have one decimal place there will always be rounding variations.

I think the amperage has to do with some of the flavors and not just wattage.

Volts, watts, amps are all inexorably tied together in a predictable and precise manner. Tweak any one and you've also tweaked the others.

Online Conversion - Ohm's Law Calculator

 

[des09]

des09, the evercool mod (switching regulator), is the best of the lot right?

There are some things I'd love to change on my evercool tekk mod... the thumbwheel dial is too accessible, so it is easy to accidentally dial up 6 volts on a 2 ohm cart, and totally burn it. The tekk doesn't stand upright, its pretty big, and the master on/off switch feels a bit chintzy. The evercool circuit is great though, it makes a charge last forever!

 

[kosliev]

I think he meant, whose responsible for the vape feel, of course voltage and resistance are the means trough which wattage and current are calculated, but they're just the cause, not the effect, therefore I'm think we can take them off the equation for now.

As you can see on my previous post, I just made up numbers so that two devices would have the same wattage, but one would have much, much less amperage on the coil.

Will these two vape the same? of course you could say "but the 16 ohm resistor has a bigger coil than the 1 ohm one, therefore the joule effect and power dissipation takes place in a bigger surface, making the vape feel the same, so resistance cant be cut out of the equation".

But you know, I dont really know, it feels like a 1 ohm atty with a raging 4Amp current in it would explode your throat with heat and boiling juice, while the 16 ohm one with just a 1Amp would make a decently warm vapor, but the wattage is the same.

 

[kosliev]

Small update, definately LiMn batteries, AW IMR, but..

Cant decide..

-regulating two 14500 or 16340 to 5.5V
-boosting a 18650 or 18500 to 5.5V

heh ;_; halp

 

[WillyB]

... Cant decide..

-regulating two 14500 or 16340 to 5.5V
-boosting a 18650 or 18500 to 5.5V

Have you ever used a standard single 14500 mod of some sort? Have you ever vaped at 5.5V?