Coil resistance, where to measure from?

[dopamine1]

Ok, I have pre made coils, I want to measure them to find out exactly how much wire I need to recreate them. Would I measure the entire length of the wire, or only the coiled portion of it?

Edit: It's got to be the full wire. It wouldn't make sense for only the coiled part to add resistance. Would it?

 

[oplholik]

I would measure the full length.

 

[yardbyrd]

CAW! There is a loud pop and YardByrd appears levitating in mid air. The platinum "YB" medallion around his neck is glowing peach and you hear a deep, smooth, male, Latin voice translating for him:

"Hail, lauds, greetings and salutations from across the Realms dopamine1. I offer an alternative to unraveling a good wick and coil to determine wire length and offer some questions and a link or two for your consideration: What gauge and make up is the wire? 22, 28, 32 gauge? What is the wire made from Kanthal ; if so what grade (i.e. A1 Kanthal) There are other wires made from other metals. These things all will influence reproducing a coil build to the resistance that you seek. Here is a link that gives a bit of information on wire types and lengths and their corresponding ohms/inch. See the first post:

http://www.e-cigarette-forum.com/forum/rebuildable-atomizer-systems/320042-resistance-wire-kanthal-nichrome-23.html

I also encourage you to go to here:

Coil Builds

Browse and search and you can find much more in depth information regarding the different kinds of wire and their corresponding ohms per inch. That way you know how much wire must be on a coil to shoot for resistance in a certain range and eventually reproduce it.

I do not intend to confuse you with this information. I personally am loathe to take apart any good build. I sincerely hope this helps you and that you will pursue, in greater depth, the surface you have scratched!" CAW!

There is another loud pop and YardByrd has vanished leaving a cloud of quickly dissolving, distinctly vanilla cupcake smelling mist in his wake.

 

[Cullin Kin]

Or you could just look at what the resistance of these pre-made coils is and use Steam Engine to tailor a build that replicates the same resistance.

Or you could do it the hard way...

 

[93gc40]

you measure between the 2 closest points of contact with metal.

 

[Nightshard]

It's not going to be the full wire in any case, since you are going to cut it once you place it in the atty, that's exactly what you should do.
Place it in the atty and measure it with the atty.

Generally speaking, the same amount of wraps and gauge, built and installed the same way, will give you roughly the same resistance every time.
You just need to start building and experiment in order to get a feel for it.

 

[Miata GT]

I see you answered your own question. To further than, figure how long each or you coil 'tails' are going to be and measure only that part along with the coil.

 

[Alien Traveler]

Premaid coils are often made from different wires. High resistance one (coil itself) is .... welded to low resistant legs. So, if you measure resistance of such premaid coil you'll really get measurements of high-resistance part (low resistance legs are too low in resistance to play any significant role in the measurement).

 

[Warpigs]

Welcome to ECF!