Prebuilt SS Coil Heads for TC - A few questions

[TooMuchOrangeTang]

Hi all,

I'm interested in trying out TC for safety reasons (primarily, being able to keep my temperature below a fixed point). I'm primarily interested in using SS coils, but I'm not at the point where I'm really ready or comfortable building my own.

Can you folks help answer a few questions for me?

1) It's my understanding that with some newer mods (DNA200, Sigelei 213, etc) Uwell's SS coils can be used in TC mode, despite the nickel legs.

That said, what are nickel "legs"? I have a pretty serious nickel allergy. Should I avoid these heads altogether?

2) Can the horizon V1 coils be used as TC coils? Does anyone know what sort of SS they are?

Thanks in advance folks!

 

[cobalt327]

Nickel legs are used to connect the coil to the atty base in a way that doesn't add unnecessary resistance. Such coils are sometimes referred to as "NR-R-NR" coils (no resistance-resistance-no resistance). Ni legs on a SS coil will work fine for TC, the mod will 'see' the greater resistance of the SS and basically ignore the Ni legs.

As far as a nickel allergy, IMHO nickel legs on a SS coil should not be a factor because the legs themselves will not be heating up enough to vaporize juice, let alone get hot enough to oxidize the nickel wire and/or off-gas anything harmful.

Haven't tried an Artic but I see no reason the Horizon v1 coils- as long as they're SS, Ni200 or Ti- wouldn't work in TC. I do not know if the SS heads are 304 or 316L, etc. though.

 

[TooMuchOrangeTang]

Thanks Cobalt!

If current passes through the legs, why won't they be heating up and outgassing/oxidizing? I'm not doubting, I just don't understand the mechanics here.

 

[cobalt327]

The Ni legs just lack enough resistance to heat up significantly compared to the greater resistance of SS wire. Put another way, for there to be enough power applied to a Ni-SS-Ni coil too cause the Ni to significantly heat up, the SS coil segment would very likely fail like a light bulb burning out. In any event, such a setup would be unvapable at those temperatures. It stands to reason there will be more heat where the Ni legs are joined to the SS coil, but there's not enough heat even there to cause problems as far as I'm aware. A shorted coil could be a problem with an unregulated device, but we're concerned with regulated TC devices that will not fire if a short exists or if the resistance is too great.

As a point of interest, factory made coil heads that use silicone/rubber insulator plugs (like Kanger Evod / Protank 2 coil heads) use Ni legs for the very reason that they don't heat up- which would scorch the plugs if they did. Now, these Kanger heads aren't made for use in TC mode by the factory as far as I know (although they can be rebuilt with TC wire and then used in TC mode), but the principal is the same as far as nickel "NR" legs not significantly heating up goes.

I should say the above assumes a 'normal' coil build. If one were to use some uber fine Ni for the leg, along w/some big gauge SS coil, you could theoretically get the Ni to heat up. But no one is going to market such a thing- there's simply no point in it.

Hopefully someone else will chime in here to add to the discussion- even if it's to dispute what I've said, it's all good!

 

[TooMuchOrangeTang]

So, if I'm understanding right, because the SS is the path of most resistance - that's where it's going to heat?

Nifty!