Why is my coil heating up so slowly
If you've gotten into coil building on mech mods or on regulated mods and have wondered why some coils heat faster than others, then this article is for you. So Why is your coil heating up so slowly ?
Are you a Mech Vaper or are you regulated ?
This is the first question you need to answer as it determines what you can and can't do with your setup. Mech Mods are limited by resistance and the continuous discharge rate of the battery in use. So what you need to do, is find a sweet spot between coil to wick coverage,ramp up time as well as temperature and battery life.
Regulated devices are easier to work with as they will collect and store power for deployment at your desired wattage (Voltage) regardless of the coil you have fitted. A Mech's wattage is determined as a direct result of the combination of the coil and the batteries voltage being pushed through them.
Knowing what watts are.
A lot of people think that when you talk about watts you are talking about electric energy. This is incorrect. Jules are electric energy. Watts are a product of electrical charge being pushed through a resistor. The product is still energy but in the case of a coil this is heat and light or radiation. Primarily in the infrared spectrum but also as visible light.
Regulated mod makers do not explicitly tell you this so most people don't know it. So think of your regulated wattage setting on an adjustable device as the wattage when used with the average basic coil. Or as the truth which is a voltage setting. If you fit a more complex coil it will not produce the same outright temperature in the same time frame.
Simpler is better for Mechs
A single 18650 tube mechanical mod can produce a maximum discharge rate of about 25A continuously. It can do this between the remaining charge level of 4.2v fully charged to about 3.7v or so remaining. This is your limiting factor. If you add loads and loads of wire in your build you'll still push the same volts using the same amps through the coil. However your surface area which is larger and more complex in say dual clapton coils requires more time to ramp up with the available power.
So the best thing to do is to keep a mech mod build reasonably simple. One of the best builds I can recommend for a great balance in ramp up time, flavour and battery life is a simple dual parallel coil for a dual coil layout or a simple 5 to 6 wrap single clapton coil. You can see there is a compromise between single and dual mode in that approach. Dual Parallel coils involve wrapping two strands of wire side by side without twisting them. 5 or 6 wraps over a 2.5mm to 3mm diameter coil jig will do nicely. One in each side of the tank or dripper for dual mode.
Because there are two strands in each coil in parallel, this drops your resistance so you get the battery life. It also doubles your surface area to wick ratio over a standard coil so you get more flavour and vapour . Crucially though it still ramps up at a similar speed to a regular coil which is better for battery safety. It's also more convenient to vape on as you don't have to wait for the vapour temperature to build up each time you press the button. This helps keep you safe with your batteries as well by preventing thermal overload.
With mech mods you generally want to avoid builds that are so low in resistance that they encourage short circuit like behavior from the battery and you need enough resistance that the coils ramp up to the kinds of temperatures needed to vape , but the compromise is that you need the surface area coverage over your wick to produce good flavour without over burdening the battery with excessive load.
Excessive load means holding the button down forever while the coil never really heats but you're well within safety limits of the cell. Low Resistance will allow heat to be produced fairly quickly but if the resistance is too low the battery may not be able to keep up and this is where you can venture into dangerous territory with battery safety. So it needs to be a balance.
As a general guide line the best 18650 cells are usually quite safe and perform well between 0.2 ohms and 2.1 ohms . If you build at 3 ohms the vape quality will be underwhelming at best and if you go below 0.2 ohms you're venturing close to the limit of the discharge rate of the battery which can lead to thermal overload.
So let's look regulated devices
Regulated devices do ultimately follow the same principles as Mechs but with a wider range of flexibility and safe guards. So for example if you build a coil with resistance too low for the device it simply wouldn't allow you to use that coil. However if your coil was just slightly pushing the battery towards the limit of it's output capability the chip would do it's best to "manage" the power output to deliver your request.
It does this by essentially storing and deploying the power that using various transformer like stages through the various components on the printed circuit board. Essentially functioning like a step up transformer but one that you can adjust to your needs within reason. So on a regulated device you can punch above your weight a bit. Similar rules apply though.
If you're using a device limited to 100 watts or less you may struggle to run dual claptons for a meaningful amount of time but the device will run them as long as it can run around 60 to 80 watts in it's offered settings. So it's better to use a dual battery mod for something with complex wire used in a dual configuration as you'll get a whole day between charges even running up to 100 watts for big builds.
If your device only offers up to 50 watts then I'd suggest sticking to simpler builds like single Clapton for example or the dual , dual parallel build described earlier.
To some things up.
So, if you're looking to use complex coils for ultra dense vapour, use a regulated device. One with dual 18650's at least to make battery life manageable between charges. If however, you like the reliability and simplicity of a mech mod or love to collect them, then just keep the coils simple. Dual parallels or twisted wire work well for dual coils setups. Single clapton's will also fair pretty well . Get ones with Nichrome 80 cores to keep the resistance load down as much as possible .
Remember to keep your mech builds for single battery devices above 0.13 ohms as the ultimate low resistance mark for use with a good cell like a VTC5A or better. If your cell is questionable then stay above 0.2 ohms for safety's sake. The same applies to complex coils. If you have to hold the button down for ages, remember that that in itself can push your cells into thermal overload on a mech. So if it's getting crazy hot, then you need to accept your devices limitations and consider simplifying the coil layout or raising the resistance.
So remember:
The more complex your coils, the harder you need to push power into them. Only Amps and Voltage can do that. If you don't have enough amps (Mechanical) then you need a chip to help you so go regulated. Watts is just smoke and mirrors really. It's something that helps to sell mods and in reality the manufacturers are talking about voltage. If you prefer mechs then know your cells and build simple enough coils that respect the laws of physics and you'll be okay.