the question is simple, is it really safe to run a 0.08 coil with an authentic battery rated for 30 amps. according to the use of Ohms law the safe limit of these batteries is 0.123 ohms of resistance, any thing lower than this increase the probability of battery failure.
Are super sub ohm coils safe
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I think you answered your own question 
Also ask yourself if you feel safe maxing your battery with a 0.12 ohm build? I don't.
Also ask yourself if you feel safe maxing your battery with a 0.12 ohm build? I don't.
Well, you already answer your question.
If the amp draw is bigger than the battery max amp output it's not safe, no matter of what ohms you are.
Ohms are not dangerous, the danger comes from exceeding that battery's amp limits.
But to be honest I don't think people that are vaping that low are using a single 18650 battery.
If the amp draw is bigger than the battery max amp output it's not safe, no matter of what ohms you are.
Ohms are not dangerous, the danger comes from exceeding that battery's amp limits.
But to be honest I don't think people that are vaping that low are using a single 18650 battery.
Not really safe, but safer than many other activities people engage in. Probably safer than kite-surfing, maybe even horseback riding. I haven't found a need to go below .3. Doubt I would go that low even if I found the vape fantastic. The key to pushing the limits is experience and tiptop equipment. If you've been vaping several years, cycle your batteries out every couple of weeks, clean your threads daily, and have an ohm meter with the precision to accurately measure to the nearest .001 ohm you have some of the bases covered to reduce some of the risk.
But the main reason not to go that low is the diminishing return. Since the mods resistance plus the internal resistance of the battery is approaching the coil's resistance, a significant amount of your battery's power is just going to heating up your mod and battery.
But the main reason not to go that low is the diminishing return. Since the mods resistance plus the internal resistance of the battery is approaching the coil's resistance, a significant amount of your battery's power is just going to heating up your mod and battery.
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Also, I'm not sure where you're getting 0.123 from.
A fully charged 18xxx battery holds 4.2 volts, at which point a 4.2/30 = 0.14 ohm coil would draw 30 amps, so even 0.123 is drawing too much current.
A fully charged 18xxx battery holds 4.2 volts, at which point a 4.2/30 = 0.14 ohm coil would draw 30 amps, so even 0.123 is drawing too much current.
You also have to factor in random chance. A brand new battery that tests out perfectly can fail even when used within safe rated limits. That is highly unlikely, but there is always some risk.
I prefer to stay well in safe operating parameters. .4 or .5 is low enough.
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I prefer to stay well in safe operating parameters. .4 or .5 is low enough.
Sent from my SM-G900V using Tapatalk
The simple answer is NO.
But why the answer is no is a bit more complicated.
So you buy a new 30 amp battery. Is it still a 30 amp battery after 100 charge cycles, and it's mAh starts to diminish?
So you build a .123 ohm coil, is it still a .123 ohm coil when it's hot, or after 100 hits? What if your ohm meter is off by 0.05 ohms?
Just like with a car engine, the closer you are to "red line" the larger the difference little things make.
But why the answer is no is a bit more complicated.
So you buy a new 30 amp battery. Is it still a 30 amp battery after 100 charge cycles, and it's mAh starts to diminish?
So you build a .123 ohm coil, is it still a .123 ohm coil when it's hot, or after 100 hits? What if your ohm meter is off by 0.05 ohms?
Just like with a car engine, the closer you are to "red line" the larger the difference little things make.
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3.7 is the "nominal" voltage. This is the "average" voltage the battery is at. Fully charged, it will read 4.2 v.
Same with a car battery. Its nominal voltage is 12v, but a fully charged good battery is more like 13.8.
I personally don't like anything below .3, myself. Too hot. But that's just me. I would think if you don't know for sure, and are asking this kind of question, you might not want to go that low yet. Again, just my take.
To answer the question directly is difficult. It's a simple question, but there is no simple answer.
I see safety as a sliding scale.
More safe - - - - - - - - - - - - - - - - - less safe.
There are few things in life that could be described as completely safe.
As TJ said, as you get closer to the limits of anything, you increase the risk.
I always calculate my amp draw based on a 4.2v battery and I always compare my amp draw to the continuous amp draw as stated by the manufacturer (using their C rating) and add in a factor of about 20% for safety (my own arbitrary factor) Based on all that, I wouldn't recommend anything on a mech with a 30 amp battery much below 0.2ohms.
Personally I don't think it's worth the risk to vape below 0.3 on a mech. This is not because I think it's necessarily dangerous, but because the risk of something going wrong increases, and the vape I get from it isn't worth that increased risk.
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