New to Mechs..

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EhCharles

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Exactly why you can not automatically trust pre-built coils or blindly trust a friend's suggestion for accuracy. The difference between 0.17 ohm and 0.25 ohm is huge at sub-ohm range. Some people argue that using a cheap $10 ohm reader is risky down to a tenth/hundreth of an ohm when a $200 Fluke digital meter has to be recalibrated every year to be precisely accurate.

Even if you use a $10 ohm reader, don't use a coil resistance that your battery's continuous discharge rating (amp rating) can not fire safely. The battery's CDR isn't a suggestion. It's the safe operating limit of the cell.

Everyone is free to set their own safety parameters, and I can only say what mine are.

I try to never exceed 50% of the CDR (continuous discharge rating) of a fully charged battery (4.2v). So with a 20A batteries, that would be 10A. An Ohm's Law Calculator tells me that a .4 ohm build is as low as I would want to use.

The reason that I place a 50% limit is because as a battery ages the mAh of the battery degrades, as the mAh degrades so does the batteries c rating (amp limit). So down the road, your 20A battery may only be a 10A battery.



This was very helpful. Appreciate the time your taking to help me out.
I like the idea on 50% of CDR hence the reason i wanted to get a 30A battery. Currently runnning 16.8 amps on a 20A Battery so im pushing it for sure.
 

bwh79

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It was an exaggerated number for how many times I calculated the build. Regardless of the amount of times i calculated it, that would not justify the "safety" of MY use. Knowledge and understanding of your build, and not only being able to do ohms law but understanding what its doing. I'm confident in my numbers and don't appreciate you picking out a negative thing to talk to about. Thanks for your time and 2 cents.
I was just ribbing you. All in good fun, I hope. My point was just that with mech mods we don't guess, we measure. And if we don't know a number, we find out, or we say "I don't know." We don't just make something up. The only time you should exaggerate is when it's for safety (i.e. we use the theoretical max 4.2 volts to calculate amp draw instead of a more realistic number that accounts for volt drop/battery sag, because we don't "know" what the real-world number is, so we just have to assume the worst and work from there.)
 

Baditude

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I like the idea on 50% of CDR hence the reason i wanted to get a 30A battery. Currently runnning 16.8 amps on a 20A Battery so im pushing it for sure.
I wouldn't call pulling 16.8 on a 20 amp battery "pushing it for sure". You are technically still within the battery's safe operating perimeter as long as it is not an older battery.

A 0.17 ohm coil will pull 24 amps, so that IS pushing a 20A battery.

Here's perhaps a wiser option. Increase your coil resistance to 0.5 ohm or slightly higher. You'll still be in that 50% safe margin of safety range but have 3000 mAh of battery time with a 20A 3000mAh battery. That's 1500 additional mAh than a 30 amp 1500mah battery.

I vape a 0.6 ohm resistance and get all day use with a 20A 3000mAh battery.
You'll likely get half that battery time with a 30A 1500mAh battery.

1.0 ohm = 4.2 amp draw
0.9 ohm = 4.6 amp draw
0.8 ohm = 5.2 amp draw
0.7 ohms = 6 amp draw
0.6 ohms = 7 amp draw
0.5 ohms = 8.4 amp draw
0.4 ohms = 10.5 amp draw
0.3 ohms = 14.0 amp draw
0.2 ohms = 21.0 amp draw
0.15 ohms = 28 amp draw
0.1 ohms = 42.0 amp draw
0.0 ohms = dead short = battery goes into thermal runaway
 
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Eskie

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The resistance on the box says .25ohms but i had put it on a mod that reads ohms and it gave me a .17, I am trying to find a tester for it at the moment as i will need it if i am to get into building my own coils.

Ah, that's the reason I asked. So your coil is really a 0.17 ohm coil (well within the wide distribution large volume coils are sold) which means on a full battery (4.2V) you're pulling 24.7A. Is that the draw you are going with? Because it sure isn't a good approach without a 30A battery. And TBH, if you want to run coils that low, you're better off with a 2 battery parallel mech. I personally would not run a 0.17 ohm coil on a single battery mech regardless of battery choice. But that's just me.
 

EhCharles

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I was just ribbing you. All in good fun, I hope. My point was just that with mech mods we don't guess, we measure. And if we don't know a number, we find out, or we say "I don't know." We don't just make something up. The only time you should exaggerate is when it's for safety (i.e. we use the theoretical max 4.2 volts to calculate amp draw instead of a more realistic number that accounts for volt drop/battery sag, because we don't "know" what the real-world number is, so we just have to assume the worst and work from there.)

Totally agree with you and of course, need every bit of information i can get aha.
So when doing my calculations, i have 18650 3.7v, but i read that you always do calcs with 4.2v just for that safety measure. Im not interested in getting my hand blown up. Trust me i was very hesitant putting the battery into my mech and firing it up. Felt like i had a remote detonator in my hand. Went over everything i had learned, checked and double checked my calculations. Even called few people ahahaha.
Really interested in building my own coils now though and learning the tweeks to adjust cloud and flavour.
 
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EhCharles

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Ah, that's the reason I asked. So your coil is really a 0.17 ohm coil (well within the wide distribution large volume coils are sold) which means on a full battery (4.2V) you're pulling 24.7A. Is that the draw you are going with? Because it sure isn't a good approach without a 30A battery. And TBH, if you want to run coils that low, you're better off with a 2 battery parallel mech. I personally would not run a 0.17 ohm coil on a single battery mech regardless of battery choice. But that's just me.[/QUOTE.

Am i ever glad that i made a post on here aha, learning more then i would anywhere else. No im not looking to run coils this low, just kind of what i gathered from the "vape store" and i bit of research.
I am going to use @Baditude 's suggestion on running a .5 ohm coil, not worried about buying to many things, just generally have an interest in building the mods and seeing what little tweeks do
 

vapdivrr

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Am i ever glad that i made a post on here aha, learning more then i would anywhere else. No im not looking to run coils this low, just kind of what i gathered from the "vape store" and i bit of research.
I am going to use @Baditude 's suggestion on running a .5 ohm coil, not worried about buying to many things, just generally have an interest in building the mods and seeing what little tweeks do
If looking at the .5 range, it brings in 26g wire as well as 24g...when I was doing mechs, .5 to .6 was my happy place, which put me in the 20 to 30 watt range. The 24g was good for this resistance, but I preferred the 26 a bit more because it heated much faster, but that's the great thing about rebuilding, so many options....good luck my friend

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BrotherBob

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Am i ever glad that i made a post on here aha, learning more then i would anywhere else. No im not looking to run coils this low, just kind of what i gathered from the "vape store" and i bit of research.
I am going to use @Baditude 's suggestion on running a .5 ohm coil, not worried about buying to many things, just generally have an interest in building the mods and seeing what little tweeks do
Welcome and glad you joined.
I have provided a little more information which might help choosing/evaluating batteries.
Might like to read:
18650 Battery Buying Guide for Vapor Users – Wake and Vape Blog
https://www.e-cigarette-forum.com/f...ics-for-mods-the-ultimate-battery-guide.4848/
https://www.e-cigarette-forum.com/f...attery-current-draw-for-a-regulated-mod.7532/
Battery Safety: Will You Marry Me? - Mt Baker Vapor
http://ecigarettereviewed.com/e-cig-charging-safety
Vaping 101: Battery Safety
 

EhCharles

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Nov 20, 2017
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If looking at the .5 range, it brings in 26g wire as well as 24g...when I was doing mechs, .5 to .6 was my happy place, which put me in the 20 to 30 watt range. The 24g was good for this resistance, but I preferred the 26 a bit more because it heated much faster, but that's the great thing about rebuilding, so many options....good luck my friend

Sent from my SCH-I545 using Tapatalk


Thanks for the advice! I went with a 26gauge .5 ohm Coil Kanthal Fused Claptons for now, i order a coil kit that has a reader and all, for now i use my kuboid as in reads the ohms (verified its accurate with a buddys reader) and also got a new VTC6 18650 3.7v 3000maH as suggested by @Baditude and hopefully will get more battery life! Was getting probably 50% of day with the LG HG2. THANKS EVERYONE FOR THE HELP!!!!
 

vapdivrr

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Thanks for the advice! I went with a 26gauge .5 ohm Coil Kanthal Fused Claptons for now, i order a coil kit that has a reader and all, for now i use my kuboid as in reads the ohms (verified its accurate with a buddys reader) and also got a new VTC6 18650 3.7v 3000maH as suggested by @Baditude and hopefully will get more battery life! Was getting probably 50% of day with the LG HG2. THANKS EVERYONE FOR THE HELP!!!!
Just depends on your vaping style....I'm just a mtl'er , so 25 watts is my preference. Some dtl at 60 watts, so that's maybe more of a thicker wire, like 24g....and then some really push a single battery mech with super low builds and even thicker wire like 20 or 22g, which imo is to much.....but yes, you can also mess with claptons, fussed, stapled, etc. Then there is parallel round coils and simple twisted round builds.....I preferred either plain round builds or parallel builds

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EhCharles

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Nov 20, 2017
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Just depends on your vaping style....I'm just a mtl'er , so 25 watts is my preference. Some dtl at 60 watts, so that's maybe more of a thicker wire, like 24g....and then some really push a single battery mech with super low builds and even thicker wire like 20 or 22g, which imo is to much.....but yes, you can also mess with claptons, fussed, stapled, etc. Then there is parallel round coils and simple twisted round builds.....I preferred either plain round builds or parallel builds

Sent from my SCH-I545 using Tapatalk


Agreed, more of a cloud chaser myself. Just rockin the tsunami mech mod at the moment with the .5 K1 coil, VTC6. 8.4 amp draw from the coil so i am well under the CDR for the battery, which for now, i am totally okay with until i further knowledge myself.
 

EhCharles

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I wouldn't call pulling 16.8 on a 20 amp battery "pushing it for sure". You are technically still within the battery's safe operating perimeter as long as it is not an older battery.

A 0.17 ohm coil will pull 24 amps, so that IS pushing a 20A battery.

Here's perhaps a wiser option. Increase your coil resistance to 0.5 ohm or slightly higher. You'll still be in that 50% safe margin of safety range but have 3000 mAh of battery time with a 20A 3000mAh battery. That's 1500 additional mAh than a 30 amp 1500mah battery.

I vape a 0.6 ohm resistance and get all day use with a 20A 3000mAh battery.
You'll likely get half that battery time with a 30A 1500mAh battery.

1.0 ohm = 4.2 amp draw
0.9 ohm = 4.6 amp draw
0.8 ohm = 5.2 amp draw
0.7 ohms = 6 amp draw
0.6 ohms = 7 amp draw
0.5 ohms = 8.4 amp draw
0.4 ohms = 10.5 amp draw
0.3 ohms = 14.0 amp draw
0.2 ohms = 21.0 amp draw
0.15 ohms = 28 amp draw
0.1 ohms = 42.0 amp draw
0.0 ohms = dead short = battery goes into thermal runaway



SO i took your advice, and am happy with the results.
Went an purchased .5 ohm coils and VTC6.
The taste is definitely there, but the cloud size has depleted for sure.
The device itself isnt warming up as much as it use to as well..
Thanks again!
 

Eskie

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SO i took your advice, and am happy with the results.
Went an purchased .5 ohm coils and VTC6.
The taste is definitely there, but the cloud size has depleted for sure.
The device itself isnt warming up as much as it use to as well..
Thanks again!

Sounds like you're in a safer place. One of the drawbacks with mechs is if you want to alter your vape to hit your sweet spot you've got to rebuild your tank with each tweak. It is also one of the benefits, as you can craft a (safe) setup that matches your preference while giving yourself time to delve in as a hobby.

Where did you get your VTC6 from? I ask only because the Black Friday sales are already running in some places. I found my usual go to, Samsung 25R, for $3.50 at IMR batteries.At that price I just got a bunch as it's always nice to have new batteries to rotate through. I saw they have the VTC6 on sale for $4.75. I don't know what you paid for yours (I assume your local shop) but having extra batteries is never bad. There are several reliable vendors for authentic batteries used around here, IMRbatteries, Illum, RTD, and a few others. If you look at the bottom of the recommended batteries from Mooch, which I'm sure has already been posted in this thread (hasn't it?) there are other reliable sources as well. Avoid eBay at all costs, as there are lot of counterfeit rewraps posted on there, and the good vendors are usually the same, if not lower, price.
 

EhCharles

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Nov 20, 2017
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Sounds like you're in a safer place. One of the drawbacks with mechs is if you want to alter your vape to hit your sweet spot you've got to rebuild your tank with each tweak. It is also one of the benefits, as you can craft a (safe) setup that matches your preference while giving yourself time to delve in as a hobby.

Where did you get your VTC6 from? I ask only because the Black Friday sales are already running in some places. I found my usual go to, Samsung 25R, for $3.50 at IMR batteries.At that price I just got a bunch as it's always nice to have new batteries to rotate through. I saw they have the VTC6 on sale for $4.75. I don't know what you paid for yours (I assume your local shop) but having extra batteries is never bad. There are several reliable vendors for authentic batteries used around here, IMRbatteries, Illum, RTD, and a few others. If you look at the bottom of the recommended batteries from Mooch, which I'm sure has already been posted in this thread (hasn't it?) there are other reliable sources as well. Avoid eBay at all costs, as there are lot of counterfeit rewraps posted on there, and the good vendors are usually the same, if not lower, price.


Thanks,

i have Moochs charts saved to a folder on my computer with his test results and his recommended batteries and as well suppliers. I purchased the VTC6 locally just as a clutch at an embarrassing price of 14.99 CAD.
But it was needed and the last time ill be doing that ahaha. Thanks for the help!
 

Eskie

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Thanks,

i have Moochs charts saved to a folder on my computer with his test results and his recommended batteries and as well suppliers. I purchased the VTC6 locally just as a clutch at an embarrassing price of 14.99 CAD.
But it was needed and the last time ill be doing that ahaha. Thanks for the help!

15 CAD?? Ouch. And as I didn't realize you're in Canada, there might be problems shipping lithium batteries from the US. If it's of any comfort, that battery will last though 300-400 charges, so useful for over a year, and it's still about the cost of one or two packs of cigarettes.

There are lots of Canadians here who probably know reliable vendors in Canada that hopefully are cheaper than that.
 
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