Rebuilding coil, high and varying ohms

[oxidus]

Hi,

Trying my hand at rebuilding some Vivi Nova coils.

2x 1mm silica wick
36 guage Kanthal A-1 Round wire
Using my Vamo to measure the Ohms (it's always been accurate before)

I first tried about 6 wraps, came out at about 9 ohms
Next i tried 3 wraps, came out at about 6 ohms
Next i tried 3 very tight wraps, came out at 3.3 ohms (getting there)

Then I just poked the wire wraps inside the coil and checked again, back up to 6.6 ohms.
Left it for a while, checked again, 3.5 ohms.



Any idea what is going on here? Maybe a short? Is it even possible to hit 1.8 - 2.4 ohms with 36 guage?

Thanks.

 

[oxidus]

Just tried it with only 2 wraps, can't go any lower. It's down to 2.8 ohms, but even with the Vamo set to 3 volts, it glows red hot in under 1 second. Maybe the Vamo is actually not correct?

 

[KenD]

36ga is very thin = very high resistance. Try some 32 or even 30ga, should also be easier to wrap

 

[Susan~S]

Coiling Calculator

Here are a few links for you regarding building coils and getting the resistance just where you want it:
1. Steam Engine
2. Coil Toy Calculator

Make sure to check your build with an ohm reader or DMM before putting it on your mod and firing it.

The Steam Engine is much more than just a coil calculator. I consider it my "All in One" vaping calculator.

 

[oxidus]

36ga is very thin = very high resistance. Try some 32 or even 30ga, should also be easier to wrap

Erm, maybe I just didn't understand the guage vs thickness. I would have thought higher guage meant thicker wire. But at the same time, I also would have thought thicker wire meant higher resistance, more wire to actually resist. Clearly some more digging is(was) in order.

2. Coil Toy Calculator

That...Explains alot. Essentially, I would never get below 2 ohms with my current wire. The fact that I got 2.6 at the moment is actually kind of impressive for me


Thanks.

 

[bosun]

I generally just use 32 gauge. six wraps on a micro coil gets me about 1.8 ohms.

A quick, copyable chart showing wire size and ohms per inch:

Kanthal A-1 Wire Specs: (Ohms Per Inch)
•28 AWG- 0.439 Ohms/in, 0.0508 Diameter (in.)
•30 AWG- 0.696 Ohms/in, 0.0100 Diameter (in.)
•32 AWG- 1.091 Ohms/in, 0.0080 Diameter (in.)
•33 AWG- 1.383 Ohms/in, 0.0071 Diameter (in.)
•34 AWG- 1.758 Ohms/in, 0.0063 Diameter (in.)

 

[Stiiinger]

Erm, maybe I just didn't understand the guage vs thickness. I would have thought higher guage meant thicker wire. But at the same time, I also would have thought thicker wire meant higher resistance, more wire to actually resist. Clearly some more digging is(was) in order.

Yeah, a lot of people get confused by this, you're not alone. Metals tend to conduct electricity very well (lots of free electrons), so the more you have, the bigger your sea of electrons to act as a transport medium for the energy. If I remember correctly, most of the flow happens near the "skin" of the metal, so the larger the circumference of your wire, the more it can conduct. A simple analogy would be a water pipe: the smaller the pipe, the more it will resist you trying to push water through it.

 

[edyle]

Erm, maybe I just didn't understand the guage vs thickness. I would have thought higher guage meant thicker wire. But at the same time, I also would have thought thicker wire meant higher resistance, more wire to actually resist. Clearly some more digging is(was) in order.


That...Explains alot. Essentially, I would never get below 2 ohms with my current wire. The fact that I got 2.6 at the moment is actually kind of impressive for me


Thanks.

the higher number gauge is actually the thinner wire;
(it's kinda like they decided 10 means 1/10 inch, 20 means 1/20 inch etc; but those arent the exact humbers; its actually related to resistance? I think, and specific to the wire alloy type)

for those coils you want 32 or 30 gauge; 30 gauge is an all round useable gauge.

You can use your 36 gauge as follows:

cut 2 six inch lengths and twist wrap them together; that will simulate a thicker gauge wire.

As for varying ohms, you are compressing the wire against metal with a rubber/silicone grommet and in a wet environment; corrosion also occurs on the surface of the wires, so electrical contact can vary anyway, especially the longer you use it.

 

[edyle]

I generally just use 32 gauge. six wraps on a micro coil gets me about 1.8 ohms.

A quick, copyable chart showing wire size and ohms per inch:

Kanthal A-1 Wire Specs: (Ohms Per Inch)
•28 AWG- 0.439 Ohms/in, 0.0508 Diameter (in.)
•30 AWG- 0.696 Ohms/in, 0.0100 Diameter (in.)
•32 AWG- 1.091 Ohms/in, 0.0080 Diameter (in.)
•33 AWG- 1.383 Ohms/in, 0.0071 Diameter (in.)
•34 AWG- 1.758 Ohms/in, 0.0063 Diameter (in.)

the above list illustrates the important thing: Ohms/inch.
the amount of wire you end up using is about 1 to 2 inches so the appropriate gauge to use if you are looking for about 2 ohms is 30 or 32 gauge.

 

[edyle]

Oh by the way, its a whole lot easier to keep rewicking with cotton; the coils last alot longer than the silica wick which falls apart after a few weeks of usage; you just poke the cotton through the coil; I resisted even trying cotton for 3 months until after I had a coil that did not work at all, and even with my old blurry eyes I found it turned out to be easy to do.

 

[techtimb]

The # of the American Wire Gauge denotes the number of times it is drawn (pulled) through a die. Therefore the higher the number the smaller the wire.


Tim

 

[AzPlumber]

the higher number gauge is actually the thinner wire;
(it's kinda like they decided 10 means 1/10 inch, 20 means 1/20 inch etc; but those arent the exact humbers; its actually related to resistance? I think, and specific to the wire alloy type)

for those coils you want 32 or 30 gauge; 30 gauge is an all round useable gauge.

You can use your 36 gauge as follows:

cut 2 six inch lengths and twist wrap them together; that will simulate a thicker gauge wire.

As for varying ohms, you are compressing the wire against metal with a rubber/silicone grommet and in a wet environment; corrosion also occurs on the surface of the wires, so electrical contact can vary anyway, especially the longer you use it.

The AWG numbering system was original set by the number of dies a wire had to pass through to reach that diameter. So a 28 gauge would need to be feed through 28 progressively smaller dies.

 

[KenD]

The AWG numbering system was original set by the number of dies a wire had to pass through to reach that diameter. So a 28 gauge would need to be feed through 28 progressively smaller dies.

Now if you guys could only use the metric system...

 

[AzPlumber]

Now if you guys could only use the metric system...

That would certainly eliminate confusion internationally but confuse the crap out of everyone here.