what exactly is sub ohm?
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Using any coil resistance under 1 ohm is sub ohm vaping. Yes, doing that will drain the battery quicker. Check out the difference using the calculator below. Raise the voltage or lower the resistance and the wattage and amperage rises, shortening vape time.
Ohm's Law Calculator
Sub means "below or less than" (sub zero, submarine). In vaping, Sub Ohm means less than one ohm in resistance. Yes, most use .5 and below to get thicker vapor from 3.7v sources in a mech where the voltage is restricted to what the battery can supply.
Most variable voltage devices control the resistance you can use as well as the amperage you can draw from the battery, so mechs are the vehicle of choice for sub ohm vaping.
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This is the first time I've heard the expression 'super sub-ohm'. Who else uses this?
Most of us would refer to anything less than 0.4 as sub-quatro-deciOhm. Kids these days...
Shorting out a battery is not a good thing to do.
Defining what value ohm constitutes a short is not a simple matter; alot of people who never thought about it will just say a short means '0' ohms, but then if a 0.1 ohm coil causes a certain type of battery to vent, then obviously 0.1 ohms is a short for that type of battery.
So, as for sub ohm, which just means 'below 1 ohm', that gives you a rule of thumb safety line; if you're over 1 ohm, you're on the safe side of the line; once you go down from there, the more you go down, the closer you get to more danger; exactly where things go bad very fast depends on your battery.
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Also: important to note: when people mention sub ohm coils, they're really talking about making coils with thicker gauge wire; because it's thick wire, the ohms tend to be lower
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A dead short can have resistance, so isn't .1 a dangerous place to live with a mech? After all, the average resistance of the leads on an non-auto-ranging ohm meter is about .4 ohms. That's after you twist the plug connections back and forth until you reach the minimum resistance/best contact.
I'm just saying that when you get below one ohm, you better know the pitfalls and the nature of the beast before you press the fire button. I can understand .8 ohm coils and maybe even .5, but no lower. With a .5 and properly calibrated meter readings, you could still be at .1 and not be aware of that.
Too many sub ohm vapers are posting about things they don't understand. Batteries aren't very forgiving in the first place. Those who push them without understanding are in shaky territory. I can't for the life of me understand why a vape shop would create a sub ohm coil for a new mech buyer. The fudge factor is tiny.
I'm just saying that when you get below one ohm, you better know the pitfalls and the nature of the beast before you press the fire button. I can understand .8 ohm coils and maybe even .5, but no lower. With a .5 and properly calibrated meter readings, you could still be at .1 and not be aware of that.
Too many sub ohm vapers are posting about things they don't understand. Batteries aren't very forgiving in the first place. Those who push them without understanding are in shaky territory. I can't for the life of me understand why a vape shop would create a sub ohm coil for a new mech buyer. The fudge factor is tiny.
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IMO the 'short circuit' and 'dead short' concepts are often misunderstood. Short circuit from Wikipedia:
"A short circuit (sometimes abbreviated to short or s/c) is an electrical circuit that allows a current to travel along an unintended path, often where essentially no (or a very low) electrical impedance is encountered. The electrical opposite of a short circuit is an "open circuit", which is an infinite resistance between two nodes. It is common to misuse "short circuit" to describe any electrical malfunction, regardless of the actual problem."
When I set up an atty at 0.3 ohms I do not think of it in terms of how close to a short it is, I look at how far from the maximum continuous current limit I am. I know that at 4.2V the draw will be 14 amps. That is the circuit I designed because I want the 40'ish watts it puts into the atty. I feel it's quite safe with a minimum 20A battery and I take care to make sure it really is quite close to 0.3 ohms.
IMO the most serious problem with a mechanical mod is to have a short circuit develop in the mod or the atty that takes the resistance across the battery down very close to zero, like what happens when a 510 pin shorts on the body. I think of this as a dead short. This scenario gives you very little time before the battery vents. It can happen to anyone too, atty resistance is irrelevant. I feel safe vaping mechanical mods only because I trust my batteries not to vent with flame when that happens to me.
Having said that, I'm not going to consider vaping at greater than continuous amp limits until batteries get better than they are now. Too much risk with not enough reward for me.
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lol my build is .18 and i have two samsung 25r's and a VTC3,4, &5 so i am not worried
I use it with a home-made chuff cap on a tobh with the air holes slotted, i should show a pic. it chucks vapor better than anything i've used before. Its a 22g macro coil 4wrap
thank god someone understands what an actual short circuit is, thank you. A short circuit, like you said, is when electricity travels along an unintended path and destroys the circuit that it is going through.
A "dead short" can occur using a wire length that has resistance (similar to .4 ohm meter leads). What makes it a short is a condition where the components along the conductive path are heated or destroyed from high amp loads that they weren't designed for.
I'm very trained and certified and have created unintentional short circuits a couple of times in my 36 year tech rep job. I maintained a territory of computer rooms and print shops and repaired high speed color and monochrome xerographic printing equipment that used extensive LSI and TTL logic voltages, 120vac and 220vac components, 300v +/- adjustable bias voltages, and 5000v electrostatic voltages. Those can create sparks and hopefully pop the breaker or load sensing electronic safety cutoffs.
The key word is unintentional. When someone who hasn't researched the ins and outs of sub ohming reads their coil and doesn't understand that meter lead resistance must be subtracted, then they may have unintentionally created a high load circuit that can be, for all practical purposes, as dangerous as a dead short (defined as 0 ohms or at least a current draw that will melt insulation or drive a battery into destruction mode). Short circuits don't have to be directly to ground. They can follow an unintended path (shortened path) through circuitry that may or may not exceed design parameters for current draw.
Hence, the reason we get posters asking why their battery is getting hot. Short, shunt, or inadvertently and poorly calculated number of turns, it all ends in disappointment, but hopefully not physical harm. My co-workers and I joked about "letting the smoke out of an IC chip". We all know that the smoke is put inside LSI components so that you will know when you have destroyed them.
I'm very trained and certified and have created unintentional short circuits a couple of times in my 36 year tech rep job. I maintained a territory of computer rooms and print shops and repaired high speed color and monochrome xerographic printing equipment that used extensive LSI and TTL logic voltages, 120vac and 220vac components, 300v +/- adjustable bias voltages, and 5000v electrostatic voltages. Those can create sparks and hopefully pop the breaker or load sensing electronic safety cutoffs.
The key word is unintentional. When someone who hasn't researched the ins and outs of sub ohming reads their coil and doesn't understand that meter lead resistance must be subtracted, then they may have unintentionally created a high load circuit that can be, for all practical purposes, as dangerous as a dead short (defined as 0 ohms or at least a current draw that will melt insulation or drive a battery into destruction mode). Short circuits don't have to be directly to ground. They can follow an unintended path (shortened path) through circuitry that may or may not exceed design parameters for current draw.
Hence, the reason we get posters asking why their battery is getting hot. Short, shunt, or inadvertently and poorly calculated number of turns, it all ends in disappointment, but hopefully not physical harm. My co-workers and I joked about "letting the smoke out of an IC chip". We all know that the smoke is put inside LSI components so that you will know when you have destroyed them.
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i set up my tobh clone with .4 ohm last night. i didn't enjoy it at all. it was on penny clone. the vape was very harsh for me. i guess it was hitting me like ton of bricks. after few puffs, i was seeing stars. so i backed out of it and when to .6 ohm. it has combination of what i was looking for. but now i'm feeling i can do little lower. with coils set up right next to the air intake, it's generating lot of vapor and i'm getting what i was looking for.. but not sure. not looking for chasing cloud or sub-ohm thing in general. looking for the setup that will give me satisfaction. but, boy.. this setup is using up lot of liquid. maybe it's time for me to start looking for right liquid with right nic level.
dude you must not of wicked it right, my .18ohm build(which would normally drink juice) gets me 3 or 4 good hits before i start to get close to a dry hit, you should research proper wicking if it isn't getting you good amount of hits off of minimal amounts of juice.
also it is high pg juice, which theoretically would make it dry up quicker or slower? anybody know if high pg juice lasts longer in a low ohm setup?
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