help building my first dual coil

[jerseyman32]

Im trying to build a 1.5 ohm dual coil, i used the steam emgine converter and it showed that i need 23 wraps with 28 gauge kanthal, so do i build two 23 wrap coils or do i split the 23 wraps between the two coils?

 

[smacksy]

Its sorta hard not knowing the specifics, and plus I've never had a need to build dual coils over 1.0 ohm...that said, I can tell you what works great for me, and without all those wraps of wire..lol.. again not knowing your specifics I can only say that generally I like dual parallel 26g builds in most of my RDA's..number of wraps depends on what mod I plan to vape it on...on my mechs, I like 6 wraps of parallel 26g on a 3mm bit for about .2 ohms..on my IPV3 (VW) I prefer 8 wraps of parallel 26g, also on a 3mm bit, at about .27-.3 ohms, that absolutely rocks in my Dark Horse vaping it at 77-80w ..sorry I couldn't be of more help..good luck!
Sent from my DROID RAZR HD using Tapatalk

 

[State O' Flux]

Although you're not offering much in the way of specifics... I can kinda guess. ;-)

28 gauge is a bit thick for a dual parallel, 1.5Ω build. If you increase the ID to 3.5mm, you can do a 13 wrap... but depending on your atty, that still might be too long (or fat).

Also, with that gauge, you'll need 50 watts or better, if you want some warmth.. and that would only get you into the 140/150 mW/mm2 heat flux.

Either reduce the resistance, or use 30 gauge... which offers a better heat flux and heat capacity, at a lower current output. You can do a 1.5Ω dual with around 11 wraps on a 2.5mm mandrel.

Last thing... click on the second hyperlink sigline below, and have a read.

Cheers

 

[jerseyman32]

Still confused about the wraps , do i split the 23wraps between the two or is that 23 wrapz each?

 

[BI00dR3D]

That would be 2 coils wrapped 23 times.
Coil Toy - Online calculator for e-cigarette resistance coil building
This is the tool I use.
Good luck!

 

[BI00dR3D]

Also that would be on a 2mm tool. Like was mentioned you could always try to go with a larger mm tool or use a higher guage wire.

 

[jerseyman32]

Thanks everyone, im going to try a greater mm to wrap on. I just wanted to make sure that i had to wrap each coil 23 times

 

[Jockamo]

Try this site. It has a picture of the build.
Coil Toy - Online calculator for e-cigarette resistance coil building

Same information as steam just easier for quick calculation in my opinion.

 

[hurricanegirl100]

23 wraps?? That will take FOREVER to heat up and your battery will be dead in under an hour...that can't be right.

 

[bwh79]

Im trying to build a 1.5 ohm dual coil, i used the steam emgine converter and it showed that i need 23 wraps with 28 gauge kanthal, so do i build two 23 wrap coils or do i split the 23 wraps between the two coils?

Resistances don't simply add together when they are wired in parallel, as in a dual-coil atomizer head. Rather, they use the formula:

R_t = 1 / ((1/R₁) + (1/R₂) + (...) + (1/R_n))

...where R_t is the total resistance, and R₁-R_n are the individual resistances. With only two, identical resistances (as they should be for a dual-coil atomizer), this simplifies to R_t=R/2, or half the resistance of each one individually. For example, with two 3-ohm coils, you have:

R_t = 1 / ((1/R₁) + (1/R₂))
[...] = 1 / ((1/3) + (1/3))
[...] = 1 / (2/3)
[...] = 3 / 2
[...] = 1.5

So to build a 1.5-ohm dual coil, you should use the calculator to figure out a 3-ohm coil, and then build two of that 3-ohm coil and wire them in parallel.

 

[HecticEnergy]

personally - when building with 28ga I prefer a .8ohm (ish) dual coil - or 2 1.6 ohm coils. Thats about 9wraps on a 3/32 drill bit. If I were to go higher, I'd use a thinner wire.
the gauge of wire has a lot to do with how fast it heats up. a .5ohm coil with 22 ga would take forever to heat, but the .8 with 28 heats up nicely.