RBA vs pre-built - Please explain

[vapervince]

Had a look at that big complex coil but to me it looks like there's way too much metal and as soon as the gunk builds up on it the performance is likely to drop off a cliff.

I'm not sure how others on here feel but I feel it's better to expose some of the bear cotton rather than covering it all up with metal. In a mesh build all the holes in the mesh leave multiple gaps where the cotton shows through and the juice can get through and I get a similar effect with my spaced wraps on my normal coils.

BTW one other little tip I picked up was that every time you take a puff and heat the coil once you stop inhaling and the coil is cooling down it fries the juice on the coil so it gunks up quicker. To slow the gunking down, if you release the fire button about a second before you stop inhaling the plain air will help to cool the coil quicker so you don't fry the coil too much.

I`m not convinced that spaced complex coils work any better seeing that capillarity needs close contact for the effect to work, the denser the fluid the larger the gap it will work with up to a point.

 

[MarylinC37]

I`m not convinced that spaced complex coils work any better seeing that capillarity needs close contact for the effect to work, the denser the fluid the larger the gap it will work with up to a point.

If you think about an electric kettle it's not just the water touching the heating plate that boils. The heat transfers through the liquid. If you allow more juice to get through past the metal coil the more juice is likely to be heated and picked up by the airflow.

 

[vapervince]

If you think about an electric kettle it's not just the water touching the heating plate that boils. The heat transfers through the liquid. If you allow more juice to get through past the metal coil the more juice is likely to be heated and picked up by the airflow.

Heat transfer in a kettle is by conduction, the movement of liquids such as in vaping is by capilliary attraction.

 

[MarylinC37]

Heat transfer in a kettle is by conduction, the movement of liquids such as in vaping is by capilliary attraction.

I certainly wouldn't claim to be the best RBA builder around on POTV, far from it. That's why I'm very interested to hear the opinions of others who know much more than I do to help identify the flaws in my ideas.

Having tried spaced wraps though I do find the flavour has improved a huge amount. Not only that but the flavour quality keeps going for longer and my builds are lasting quite a bit longer.

As well as heat transferrance through the liquid, the other thing I feel helps a lot is the secondary function of the juice which is to act as a coolant around the wraps so you heat the coil just enough to produce lots of vapour but then more juice surrounding each wrap helps the coil cool down quicker which slows down the gunk build up. I also need less watts on my mod so for me, even on a complex coil, spacing the wraps has definitely helped a lot.

I see what you're saying about the movement of the liquid in a kettle but the juice in your vape isn'y static. The capillary action in your vape is also causing the juice to flow through the cotton as it sucks the juice through.

 

[vapervince]

Not everything can be explained by numbers, especially a vapers taste preferrence.

Capillarity works until your cotton and coil become saturated ( or the force of gravity outweighs the attraction), what appears to be suction is juice being replaced as the juice higher up the wick is evaporated.

 

[Crispycritters]

I find spacing means the centre of the cotton is less likely to burn through, occasionally when I come to re-wick/cleanup I find the centre of the cotton has burnt away when I use contact coils, I've never had this happen using spaced coils. On the other hand I find spaced coils a bit more prone to spitting, but this isn't absolute - most of the time I don't have spitting problems with either contact or spaced coils so it could easily be a case of me not getting the wicking right.

I can't say I've ever noticed any difference in capillary action - any time I've had a problem with the vape from an RTA feeling dry its because I've overstuffed the juicewells, or burnt out the centre of the wick/s.

 

[vapervince]

Compared to some of the building videos I use far too little cotton but I cant remember the last time I had a dry hit, and the last leak I got was through over squonking.

 

[Reti]

Before considering buying something like that it's probably first thinking of what the typical wattage is that you prefer to vape at AND are those coils going to fit in your RDA/RTA. Just looking at the specs - the cores are Kanthal 0.4 ribbon wires, probably 0.1 x 0.4, and there are an awful lot of cores - plus the frames, which as you can clearly see makes them really wide so you stand little chance of actually being able to fit them in in the clamping holes of your aromamiser. In addition to that they have a LOT of mass so they will take a long time to ramp up unless you throw a ridiculous amount of power at them which means a lot of heat so you need air inlets the size of the Mersey tunnel to keep the heat to acceptable levels. If you like vaping at up to 80 Watts I can pretty much guarantee you won't like a 160 Watt vape.

Sorry bud, a lot of complex coils are good but going larger and larger doesn't necessarily make them better - and those will only work for the tiny percentage of vapers that like extremely high power levels and like large wide open RDAs with no air restriction. Personally I would stay clear of them and would never put a coil that size in any RTA.

On the subject of Aliens - there are the good ones, like the ones in the pic, with the wavy outer wrap that generally have 2 or more cores. Alien refers to the 'S' shape of the outer wrap - there are many different types with different core wires but 'alien' refers to the outer wrap. Sometimes they are labelled 'snake aliens'.

Then there are the shit type - most that I have seen have a 0.3 x 0.8 single core wire and a 32ga outer wrap. The outer wrap of these coils will be regular clapton style - not the 'S' shaped outer core and multiple inner cores of the good ones. In reality they are flatwire claptons - but they're not good quality flatwire claptons. They're cheap nasty crap marketed by con men IMO.

the manufacturers of these flatwire 'aliens' claim that the very first aliens were a claptoned flatwire type and that is why they label them as such. even if they are telling the truth they are taking the piss, most vapers will automatically think of the 'good' type of aliens with the S/snake outer wraps and buy accidentally becausde they thought they were getting something else. i bought a 15 foot spool of it about 5 years ago and still have about 14 and a half foot left... I plan to use it to tie up my bin bags because it's shit. Don't fall for it mate - every coil in that coilology multi-pack is better, including the mediocre Juggernauts lol.

About that multi-coil pack. I noticed that some of the coils look just exactly the same as some other ones, despite being named differently. For example, the framed staples looked exactly like a fused clapton and just like a staple. I emailed the shop (SR Vapes) and mentioned this. He called me later in the day and explained that the coils are shit and he checked his other packs and they're the same. He said they're just there for new vapers to pick what kind of coils they like but not to expect anything good. He said they're all machine made, cheap shit coils lol. He said Coilology aren't shit and they have some good coils, but that multi pack isn't good.

I've ordered some nice hand made ones. Just need to wait for them to arrive.
But yes I have noticed some people selling coils on ebay are claiming fused clapton looking ones are aliense. I've ordered some proper handmade aliens from a shop with 100% positive feedback and lot's of sales.

 

[MarylinC37]

I agree with @vapervince about the numbers. I think we often get to obsessed with numbers and don't think enough about what else is happening inside our attys.

I also agree that the capillary action of the cotton won't really become better on it's own. Having all these nice coils with all their nice shapes and different amount of cores is great when they're all clean and new but then you have to factor in what happens when the gunk starts covering it all up.

With a contact coil, particularly where it has a covering of gunk, there is very little space where the juice can get to the surface except at the two ends. Heat transferrance will heat a certain amount of juice around the sides but almost nothing through the centre between the wraps because of all the metal and gunk covering the cotton.

 

[Reti]

I think silica is aka glass fibre.

Yes. Here's what a guy on another forum has said about their safety when I was Googling them...
The "dangers" of silica wicks | E-Cigarette Forum (e-cigarette-forum.com)

Safe apparently. But they shrink when wet rather than swell. But their good part is you can't burn them and dry hits aren't a thing.