Old Vaper New to Mechs - And my Mechs just arrived

[Archer74]

So my StingRay and Nemesis just arrived. Currently have 25Rs on hand with VTC4s and HG2s en route. I've been reading up on using ohm's law, mechs, and batteries. Right now 3 of my rda's have 0.5, 0.43, and 0.32 builds so they're in the 'safe' 20amp rating of my batts... Right? So I'm fine if I stick with the list below:

Looking @Baditude blog

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 <------ lowest for any well known, properly rated, authentic 20amp battery
0.2 ohms = 21.0 amp draw <------ lowest I 'could' push the VTC4s, right?
0.1 ohms = 42.0 amp draw

 

[State O' Flux]

With unregulated mechs, you also must take into consideration, an "optimized" build for the wattage provided... per Ohm's law.

For example... lets take the Ohm's law value for 0.4Ω @ 4.2 volts. 10.5 amps insures that you are well within the battery amperage potential, but other than the desired resistance, that doesn't help you with producing a build optimized for the available wattage.

To optimize a build, you need to consider values of perceived vape temperature (heat flux) and maximized coil net surface area. Heat capacity is also a critical consideration... the value representing time-to-temperature efficiency.

Too thin a wire, or not enough coils in parallel to distribute the wattage... and the vape will be too hot, with minimal surface area. Too thick a wire, or too many coils in parallel and although the surface area will be very good... the vape may be too cool for your tastes.

If you've not used a coil modeling calculator, I suggest you click on the sigline hyperlink below regarding the advanced use of Steam Engine. With that, you'll be able to optimize your build for use with an Ohm's law derived, wattage availability.

 

[Bad Ninja]

So my StingRay and Nemesis just arrived. Currently have 25Rs on hand with VTC4s and HG2s en route. I've been reading up on using ohm's law, mechs, and batteries. Right now 3 of my RDA's have 0.5, 0.43, and 0.32 builds so they're in the 'safe' 20amp rating of my batts... Right? So I'm fine if I stick with the list below:

Looking @Baditude blog

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 <------ lowest for any well known, properly rated, authentic 20amp battery
0.2 ohms = 21.0 amp draw <------ lowest I 'could' push the VTC4s, right?
0.1 ohms = 42.0 amp draw

Yep. You are good.
I reserve builds below .25 ohms for dual battery mechanicals.

 

[Archer74]

With unregulated mechs, you also must take into consideration, an "optimized" build for the wattage provided... per Ohm's law.

For example... lets take the Ohm's law value for 0.4Ω @ 4.2 volts. 10.5 amps insures that you are well within the battery amperage potential, but other than the desired resistance, that doesn't help you with producing a build optimized for the available wattage.

To optimize a build, you need to consider values of perceived vape temperature (heat flux) and maximized coil net surface area. Heat capacity is also a critical consideration... the value representing time-to-temperature efficiency.

Too thin a wire, or not enough coils in parallel to distribute the wattage... and the vape will be too hot, with minimal surface area. Too thick a wire, or too many coils in parallel and although the surface area will be very good... the vape may be too cool for your tastes.

If you've not used a coil modeling calculator, I suggest you click on the sigline hyperlink below regarding the advanced use of Steam Engine. With that, you'll be able to optimize your build for use with an Ohm's law derived, wattage availability.

Great info on that, thanks! that narrows my coil building quest by a lot. I bought several spools of different gauge wire to experiment with to find my ideal coil build.

 

[MattyTny]

State O' Flux pretty much nailed it down for you.

Something like this works well on a mechanical. It's a 26 gauge dual that reads around 0.5ohms.
http://www.steam-engine.org/coil.asp?a=true&s=dp&r=0.48&hfnw=33&awg=26&id=2.5
The coil diameter is up to you. I have two mechanicals that run a similar build, one with a 2.4mm ID w/ 9 wraps and one with a 2.8mm(7/64) ID w/ 8 wraps.
Both are a very medium temperature vape and heat up fine.