hello I’ve recently bought an rda and am planning on getting a coil building kit, but I have no clue what an ohm reader does, I know it tells you the ohms but why do you need that, and I plan on putting my rda on a smok t-priv until I get a mech mod, so any and all information on ohm readers will help.
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If you plan on building coils you need to know ohms law and battery safety. If you are looking into getting a mech then you really need to know both. If not you can blow up or vent a battery causing damage to the mod or yourself. There is no safety devices on a mech mod. Look at http://steam-engine.org/ and put in what wire type, size, and ID(inside diameter) to see what your ohms should be at. What type of coils are you thinking of building? I started with just single strain wire at 0.7-1.1 ohms. This was used on a regulated mod for a while to learn how to build and make sure there were no problems. I got some clapton wire and went down to 0.35 ohms. Still safe with my device and battery. Look at mooch's battery write ups for battery safety.
An ohm reader measures the resistance of (in this case) your coil. The reason you need one, is a regulated mod will not work above 3.0 ohm or below 0.10 ohm restance. (usually for most reg mods). As you say you plan on getting a mechanical mod, it becomes even more important. Mech mods have no safety or protection circuits built in. The resistance of your coil determines how many watts are sent to the coil and how many amps your batteries have to push to provide those watts. Watts = voltage square / resistance. Now we rate our batteries by CDR (constant discharge rate in amps) and run time (Mah) *how long the battery lasts between charges*. CDR is actually the amount of amps your battery can safely generate without over heating and venting. A battery with a CDR of 20A will handle a coil at 0.21 ohms and generate 20A. So if the power button got stuck, your battery would discharge but not over heat or vent. The lower your resistance, the higher above your rated CDR you go. A 20A Samsung R battery is still resonably safe even at 29 amps.... at 30 it will over heat. (suggested to stay at 20A or below) The more amps drawn from the cell, the faster they heat and the less time you have to react and handle the situation. With mechs, the idea is to build better coils to run at your batteries CDR and not just build at lower resistance because you saw some idiot do it on youtube without explaining what battery he was using or the stress limits on that cell and a dozen other bits of information you need to know.
Steamengine.org will help you determine how many amps your coil will draw and also how much heat the coil will produce at XX watts. (say 400mw/mm2 at 125 watts) for example.
This is why you only see us recommending brand name, high drain batteries. Samsung, Sony and LG print accurate ratings on the label.. example.. 20A 3000mah or 30A 2000mah. Brands such as efest or Imfire rewrap batteries and may (and usually do) exaggerate the CDR. There is no such thing as a 45A 3000mah battery, regardless of what ebay and the label try to tell you. Never take "pulse ratings" into consideration. These are not accurate as they do not explain how long they fired the cell for, how much the temperature rose, how long they rested the battery between firings, etc etc. At the listed pulse rating, a battery will over heat and vent in your pocket if accidentally fired.
Steamengine.org will help you determine how many amps your coil will draw and also how much heat the coil will produce at XX watts. (say 400mw/mm2 at 125 watts) for example.
This is why you only see us recommending brand name, high drain batteries. Samsung, Sony and LG print accurate ratings on the label.. example.. 20A 3000mah or 30A 2000mah. Brands such as efest or Imfire rewrap batteries and may (and usually do) exaggerate the CDR. There is no such thing as a 45A 3000mah battery, regardless of what ebay and the label try to tell you. Never take "pulse ratings" into consideration. These are not accurate as they do not explain how long they fired the cell for, how much the temperature rose, how long they rested the battery between firings, etc etc. At the listed pulse rating, a battery will over heat and vent in your pocket if accidentally fired.
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Ohh okay so, the ohm reader is for telling me the ohms that the coil will output and how many amps my battery will need to be able outsource this to my coils safely and with messing up my mod? (Correct me if I’m wrong)
So how do you read how many amps your coil will output? From the ohms?
If you don't know what an ohm meter is you shouldn't be messing with a mech mod. If you don't have a firm understanding of how coils and batteries interact a mech mod will be dangerous. For example, ohms are not output they are measured.
You would be better off with a regulated mod because they have safety features which will protect you from some of the risks of coil building.
If you get a variable voltage / variable wattage regulated mod it may include an ohms reader which can tell you whether your coils are safe to use.
I will also suggest you get over to youtube and watch a few video tutorials on basic coil building to get a general overview of how it works.
As gbalkam said above Steam-engine.org is a great tool for building.
Good luck with your RBA.
You would be better off with a regulated mod because they have safety features which will protect you from some of the risks of coil building.
If you get a variable voltage / variable wattage regulated mod it may include an ohms reader which can tell you whether your coils are safe to use.
I will also suggest you get over to youtube and watch a few video tutorials on basic coil building to get a general overview of how it works.
As gbalkam said above Steam-engine.org is a great tool for building.
Good luck with your RBA.
Oh, so the ohm is just a reading okay. I watched a video on ohms law a couple times and still trying to wrap my head around this, it think I get the idea but I want to be safe while vaping so any and all corrections are welcome, so what I got what was, I = V/R, which is, current = voltage/resistance, and that the resistance is the ohms and the voltage is what your batteries norminal voltage, and so what this equation will give us (I = V/R) is the amps, and depending on my batteries, will tell me how many amps are be produced.
The below pic showing the relationship between Power, Current, and Voltage might be helpful. Just keep in mind that while the formulas below can be applied directly to a non-regulated (mechanical) mod, for a regulated mod like the Smok T-Priv which has electronic circuitry, the equations apply to the input to the circuitry (battery side) and to the output from the circuitry (coil side) separately. This is because regulated mod circuitry uses buck-boost or switching circuitry to change the output voltage (that's why the voltage to the coil can be lower or higher than your battery voltage).
The safest way to ensure you have a battery adequate for the power you want to vape at on a regulated mod is to compare the calculated current to the continuous current rating of the battery using the following formula:
Ibatt=square root (P/R) / eff, where P=power setting in Watts, R=coil resistance in Ohms, and eff = Efficiency of the mod -If you mod doesn't have this spec, I suggest using 0.85, a conservative number at higher powers.
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Must watch vids for anyone who uses removable battery vape devices.
https://www.youtube.com/channel/UCePHh3NMvu3rW2LFJeOWo-Q
https://www.youtube.com/channel/UCePHh3NMvu3rW2LFJeOWo-Q
Okay okay, I’ve been doing some research and I think I have an okay understanding, still gonna do more research but just making sure I’m thinking about this right. Okay so the ohms is the measure of resistance that your coils have and so you get your normianl voltage, let’s say 3.7 and divide those numbers to give you your ampsso let’s say the ohm was .6 so 3.7/.6 is 6.16666 Amps and this how many amps will be used from your battery, and so you need a battery that can support that many amps or else is may pontentialy blow up.
That is the barebones of it.
Geta a bit more complicated with regulated vs Mechanical mods. But you have the basics.
Handy little website.
http://www.ohmslawcalculator.com/ohms-law-calculator
Also handy.
http://www.steam-engine.org/
www.steam-engine.org is your best friend
If you are thinking about getting into Mech's I very highly recommend getting proficient with building first. Then once you're proficient with rebuilding and if you're thinking about getting a Mech read through this before you start.
1. Ohm's law, http://www.steam-engine.org/ makes it easy and there's even an app on it for Android
2. Batteries, fucking batteries, take good care of your batteries and know them!!!!!!!!
a. Avoid shit batteries like eFest who rewrap rejects with grossly inflated amp ratings. Stick with authentic LG, Sony or Samsung from reputable (not ebay or amazon) sources, great places to get authentic are from
http://liionwholesale.com/
https://www.imrbatteries.com/
https://www.illumn.com/
b. Stick well within Continuous Discharge Rate (CDR) Not the "pulse"
c. Keep up to date with what Mooch tests and battery ratings, follow his posts on Facebook and his Blog
d. In Mod's with multipule batteries, marry them.
e. Get some battery wraps, they're cheap and easy to re-wrap batteries. Any nicks,tears or what ever don't be stupid and just re-wrap.
3. Don't build stupid low a good builder can chuck and get awesome dense vape from a good build. It's simple, with 20 CDR Amp batteries -
a. Single battery mod's you're fine with .2 ohms on up
b. Dual Parallel you're fine with .15 on up. Parallel you take the full CDR of one battery and you can add 1/2 the amp rating of the next battery
c. Series you double the voltage but you share the amp. So a series you build high with a lot of wire, no lower that .4 ohms.
4. Make sure you don't have any shorts. For an extra caution any new build I vape on a regulated mod for a few drips or with a tank about a 1/4 tank. This is to insure nothing wonky with my build or any shorts.
5. Careful if it's not in your hand, if it doesn't have a lock on the button and you pit it in your pocket (which I really don't recommend) insure nothing else is in your pocket and it's loose. Don't want to put it in your front jeans pocket and blow your dick off ya know
6. Last but certainly NOT the least, keep it clean! Clean it when you first get it "before" you even use it and clean it on a regular basis.
a. Ultrasonics are a very good investment, got mine off Amazon for around $25.