So it really doesn't matter if the coils are touching each other when rebuilding coils?

[supermarket]

So, now that microcoils have become a thing....it is obvious (I guess) that it is okay for the wraps on the coil to touch each other. This is pretty confusing, because before micro-coils became a thing...I read on here tons of posts about making sure there is enough space between each wrap, so that the coil doesn't touch metal to metal.

Can someone clarify what the deal is with this?

The reason I am so interested, is because to me....it seems like it would be COMMON SENSE that the MORE wraps you have, the more SURFACE AREA is covered on the wick, thus causing a better vape.

Right now, with rebuilding coils for my pro tank, I use about 4-6 wraps of 32g kanthal. If the coils are okay touching each other, I would MUCH RATHER use 30g kanthal, and add more wraps, to cover more of the wick.

Honestly, it would seem to me, that the more wraps you can do, the more of the wick that gets covered by the coil, thus you will have better flavor, more vapor, etc.

Hoping some others can clarify this for me.


Also, another question. If it doesn't matter if the wraps touch each other....what is the benefit of spacing the wraps out? I know for me, it would be MUCH, MUCH easier to wrap my 32g kanthal with each wrap touching the one before it....

 

[Nermal]

Disclaimer: I have never wrapped a coil in my life.

With that out of the way, it sure seems to me like every place one wrap touched the next, you would have greatly lowered resistance per coil. If all were touching one another, it sounds like an almost zero ohm condition. If someone could tell me why I'm wrong, I would definately take time to read.

Sorry Supermarket, but at least I bumped the thread up for you.

 

[alangoooo]

I've watched countless videos over and over again, and microcoils DO create more vapor but I also think it depends on the materials used and the voltage and all that. but I also noticed microcoils have extremely low ohms. personally I think that's super advanced stuff and not yet for me, and I admit I tried making microcoils from a video but it wasn't that much better than my normal coils I wrap. but I'm sure it's because I didn't make good microcoils.

 

[retired1]

Moved to Rebuildable Atomizer Systems

 

[Ryedan]

This was my first micro coil:



I'm still using that coil after over a month BTW. I do a better job of wicking it now though

I believe at least some of the coils are touching. I did torch it while holding the coils together to get them as tight as possible. It works. No shorts and no changes of resistance. It's totally stable and vapes very well.

I have never tried many coils on a standard build, so no idea how much you would gain from that. My other vape is a AGA-T with SS wick. I have the 3/4 coils about evenly spaced with about a mm between them. I would not worry too much about coils touching as micro coils do, but I would not cross coils. I suspect that could become a short risk and be unstable. Hopefully someone who has tried it will see this and let us all know

 

[Jazzi Mike]

With microcoils, it actually is good that the coils touch each other and helps give it its better vapor. However, if you are building a normal coil, it probably would not work out well if some of the coils were touching.

 

[Spazmelda]

With microcoils, it actually is good that the coils touch each other and helps give it its better vapor. However, if you are building a normal coil, it probably would not work out well if some of the coils were touching.

Yeah, but why? I wanna hear some physics!

 

[timk]

Yeah, but why? I wanna hear some physics!

With all of the coils touching, the mass has been condensed. You now have tube that heats up as one unit instead of a coil of wire heating up at what seems to be random. I know this isn't much for physics but it's a start. All I know is microcoils heat evenly and predictably every time.

 

[LucentShadow]

It would be exceptionally difficult to get a helix (coil) with any significant mechanical friction between each turn. They will naturally tend to keep a very small gap no matter how tight you wind them. Why? Don't know, don't care, but I'd guess that it's a property of the helical shape and metal composition.

Both Kanthal and Nichrome form a very thin layer of metal oxides on the surface. Largely aluminum oxide for Kanthal, and Nickel oxide for Nichrome. These oxide films increase when the wire is heated, but form in the presence of oxygen, and are electrically non-conductive. It does not take much mechanical friction to remove them, but there generally isn't much to be had in this application.

I would try to avoid any twisting or crossing in any place where you would not want a short, as I think it would be more likely there.

Whatever type of coil that you make, even spacing of the turns is generally a good idea, as it promotes a more even temperature across the coil. 'Micro coils' tend to concentrate a lot more heat in the middle of the length of coil than a more spread-out coil does, though, due to the close proximity of the individual turns.

 

[ScottP]

The reason the coils can touch without shorting is two fold. First is "surface tension" much the same way a car can hydroplane on the surface of water even though it should sink there is a slight layer of surface tension where the wires touch that keeps the electricity flowing through the wire instead of between the coils. Second is oxidation. As the coils are torched, flamed, and dry burned to get the shape right they build an oxidation layer around the wire that creates a thin layer of insulation that also helps keeps the electricity from jumping coils. These work due to the relatively low voltages we are working with. If we were trying this with higher voltages, say 110v, we would need more insulation/oxidation/space to prevent the shorting.

Interestingly I have a 15,000 (15kv) volt transformer (from a helium neon sign) that I built a Jacobs Ladder out of. With that level of voltage you can create arcs across several inches of space.

EDIT: For those interested here is an interesting article that explains how a jacobs ladder works: The Physics Behind The Jacob’s Ladder | Deskarati

 

[Nermal]

Thanks, Scott. I've seen the same effect when a sleeve or something like that is pressed into a larger part.

 

[Rmcgloth]

It's all about flow. Electrons take the easy path, and generate heat when backed up. When coils are spaced evenly, tight or loose, it looks like a well ordered freeway, some resistance due to the structure and density of the wire, but not too much in any one place. A crossed coil may act like a crossed lane on the freeway, collisions and slowdowns, causing a hot spot. Other sections get bypassed and have less flow through them, staying cool and not vaporizing. All similarly close, wether tight or loose, the whatever floats your boat.
Btw all oft he above posts are correct, as a music teacher I tend to go for the common analogies before the science. I do love that there are people here that can describe things in correct terms! ( even though I haven't used the term mechanical friction since high school

 

[supermarket]

Thanks for the answers everyone...although I think I'm still just as confused, lol.

 

[super_X_drifter]

It matters greatly. I'm not sure about what gains you will see in coils with a larger inside diameter than 1/16" but when you wrap one that is 1/16" ID or slightly smaller with touching wraps you produce a micro coil - like this:

It's one sweet vaping hotspot

 

[vang0gh]

I've watched countless videos over and over again, and microcoils DO create more vapor but I also think it depends on the materials used and the voltage and all that. but I also noticed microcoils have extremely low ohms. personally I think that's super advanced stuff and not yet for me, and I admit I tried making microcoils from a video but it wasn't that much better than my normal coils I wrap. but I'm sure it's because I didn't make good microcoils.

Micro coils aren't just for low ohm builds. In fact, I believe the guy above me (inventor of the micro coil btw) builds his micros in the 2.0 ohm range. My micro coil preference usually runs between 1.2 and 1.4 ohms. Personally, I find that building a micro coil is easier than wrapping a coil around a piece of silica wick.

 

[vang0gh]

Thanks for the answers everyone...although I think I'm still just as confused, lol.

The simple answer is that, for whatever reason, they can touch. In fact, if there's a gap between the coils in one of my micros I heat it and squeeze all of the wraps together with tweezers until all of the gaps are gone.

 

[Plumes.91]

I've actually wrapped coils in a repeating X pattern and they have lasted just as long as coils wrapped & evenly spaced. I used to think coils couldn't touch until I gave a new builder some rebuilding advice and said "make sure the coils don't touch" and I got a couple responses below me to the tune of "The coils can touch, whoever said coils couldn't touch is a vaping sadist that doesn't want you to have fun rebuilding" and ever since then I have worried less (or not at all) about my coils touching. The key is even spaces if you do space them out and avoid hot spots, which can be caused from spacing them out except for 1 area of the wick which causes a hot spot that will burn or short/snap due to the extreme heat in the 1 area.

 

[panomano]

In micro coils current does not travel through the wrap because the coils are touching. I have ohmd out the wire before and after coiling it in a micro coil and its the same. The reason you want the coils touching is because the closer they are, the more concentrated the heat is when firing. You can have a micro coil setup that throws out as much vapor as a sub ohm traditional coil setup due to this.

 

[Kyi]

How many spirals for something around 2.0 (give or take) with 32, 30, and 28 gauge wire? I would like to try this on my VV mod.

 

[Plumes.91]

How many spirals for something around 2.0 (give or take) with 32, 30, and 28 gauge wire? I would like to try this on my VV mod.

The question is relative to each one of those wire gauges, the circumference of your wick, and the space within your rebuildable.