Building Your First RDA - A Bombies Tutorial

[Alex]

Building Your First RDA - A Tutorial
Posted by Bombies on September 28, 2015

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A good chunk of our crew likes to use their RDAs over their tanks while they’re at home or at the office. RDAs provide a ton of freedom for controlling the characteristics of your vape, and often times provide significantly better flavor than tanks (although it should be noted that this is changing, with new RTAs getting closer and closer to the flavor and vapor production of RDAs). For many, however, getting into dripping seems a daunting task. Rebuildables require an intimate knowledge of ohm’s law and at least a modicum of patience. No one does a perfect build on their first try, but stick with it and you’ll find that rebuildable atomizers not only offer more freedom and control, but save you a good chunk of money over prefab coils. With pre-built coils costing almost $5 a piece, rebuildables reduce the cost of vaping by more than $4 a coil. A spool of wire costs around $7, and that’s for 100 feet of the stuff. Cotton is another $8, and assuming you have a screwdriver set and some wire snips (or nail clippers, if you’re in a pinch) - the sum total of investment required for rebuilding is only around $20. That’s the cost of a 5-pack of coil heads for many of the popular atomizers on the market right now.

So, you want to get started rebuilding? Well, grab your RDA and build supplies, cause it’s time to talk about:

Rebuildable Dripping Atomizers: Getting Started


Let’s assume for a moment you know nothing about drippers . It’s ok, we all started at that spot. You’ve heard things from the guy or gal at your B&M, or online. You want to dabble in it and see if it’s for you, but you don’t know where to even begin. What do you buy?

Well, recently we did a post about our five favorite atomizers. This post included three drippers: the Derringer, the Mutation V4 and XS, and the Vector RDA. Each of these choices offers a unique set of features that will help increase flavor, cloud production, and make building easier. If you’re just trying to get your feet wet, I’d suggest the V4/XS for its easy to build on 4 post deck, multitude of airflow configurations, and easy-on-the-wallet price point.

Building terminology

If you already know all this terminology, feel free to skip down to the build tutorial!

When you read about new builds, or people mention their builds online, there might be some terminology you’re not familiar with. Chances are you’re at least partially familiar with the term “ohms” (represented with the Ω symbol). Ohms are a term for electrical resistance across a circuit, which in our case is the coil. In an analogy, coil resistance is a lot like a hose with water coming through. The smaller the hose, the more force is needed to push the same amount of water through in the same time. In this analogy, that force is voltage, and that water coming out is measured in watts (as a measure of power of the water leaving the hose). If I have a 1/8th inch hose, and need to push 1 quart of water through it in a set timeframe, it will take a lot more force than if I’m using a 1/4th inch hose. Likewise with wire, if I’m trying to fire my coil at 30 watts, the coil with more resistance will require more voltage (force) to achieve this.

• Ohms - Electrical resistance across a circuit
• Volts - Electrical force behind a current
• Watts - Measure of electrical energy across a circuit

There are multiple guides out there that can explain Ohms, Volts, and Watts in much better detail than I can - and they will also cover Amps which are vital to battery safety. I highly suggest reading or watching one before diving into building.

Now, for some more terminology.

Wires

• Gauge - Wire gauge is a measure of the thickness of a wire. The thicker the wire, the lower the number. 24 gauge is thicker than 26 which is thicker than 28. With wire gauge, resistance per inch increases when the size decreases. So 24 gauge (sometimes written AWG) is less resistant than 26 AWG which is less resistant than 28 AWG and so on.
• Nichrome - Nichrome is a wire material that uses a blend of nickel and chrome. Nichrome is lower resistance per inch than kanthal at the same gauges, allowing mechanical mod users to achieve higher wattages from the same builds. Be advised though that Nichrome can be dangerous if you have nickel allergies.
• Kanthal - Kanthal A1 is the standard coil wrapping wire in vaping. It’s a blend of typically Iron, Chromium, and Aluminum, and has a slightly higher resistance per inch than nichrome wire of the same size
• Nickel - Nickel wire is used exclusively for temperature control. Nickel wire is very low resistance, but has the unique property of changing resistance as it heats up. Temperature control enabled mods read this resistance as it changes to moderate the temperature of the coil and prevent wicks from burning. DO NOT BUILD WITH NICKEL WIRE UNLESS YOU ARE USING A REGULATED DEVICE WITH TEMPERATURE CONTROL FUNCTIONS.
• Titanium - Like nickel, titanium wire is ultra low resistance wire used for temperature control applications. It’s an alternative to nickel for those with allergies. DO NOT BUILD WITH TITANIUM WIRE UNLESS YOU ARE USING A REGULATED DEVICE WITH TEMPERATURE CONTROL FUNCTIONS.

Wicks

• Japanese Cotton - Japanese cotton is a type of cotton pad that has all of its fibers aligned in a more or less parallel fashion, allowing for faster wicking an easier wick sizing. Japanese cotton is often touted as “one of the best” options for wicking.
• Cotton Balls - Cotton balls or just loose cotton is a common wicking material, and it fairly easy to work with. Just pick off a small amount and roll and shape it to size for your coil. Straightforward and simple. The downside with some cotton is that it retains a very strong cotton taste for awhile. It’s important when using cotton balls or loose cotton to find non-bleached, non chemically treated cotton.
• Rayon - Rayon is a synthetic alternative to cotton for those with cotton allergies. It doesn’t have a strong taste like cotton does, and is said to wick rather well. It’s also cheap as sin.

There are many other alternative wicking materials out there - enough to do an entire article on in and of itself - so do some research if you don’t find any of these suggested options to your liking.

Let’s bring all this terminology together now with an overview on building your first coil.

The Moment of Truth: Building your first coil

You will need the following to get started building:

• Wire (for this example I am using 24AWG Kanthal)
• Wicking Material
• An RDA (The pictured RDA is a Mutation X V4)
• A precision screwdriver set or drill bit set
• Tweezers or Needlenose Pliers
• Wire Snips (or nail clippers if you’re in a pinch)
• Scissors (optional)
• Ohm Reader (especially if you’re building on a mech mod)

We’ll start off with a simple .3 ohm dual coil. This should be safe to run on any quality battery like a Samsung 25R or LG HE2, and will provide plenty of flavor and vapor. For this build, I use 24 AWG wire. If you don’t have 24 AWG, that’s fine - these build “mechanics” apply to all wire gauges.

Start by cutting two lengths of wire around 6 inches each. Using a drill bit or precision jeweler's screwdriver that’s 2.4mm in width (roughly equivalent to a 3/32 drill bit). With one hand, hold the drill bit or screwdriver firmly. Take one length of wire and lay it over the bit, so that it’s perpendicular to the driver. Make sure there’s at least half an inch of wire hanging off the edge - this is your lead, you’ll need this to secure your coil to the RDA later. Holding the wire to the bit or driver firmly, take your other hand and use it to tightly pull the wire around the bit so that you’ve completed one wrap. Now repeat this process again. You should have two wraps parallel to each other, touching but not overlapping.

Keep wrapping until you have done this process 8 times.

Now, repeat the same process again with the other length of wire. You should end up with two 8 wrap coils. It’s important that the number of wraps on each coil be the same, or one will heat up much faster than the other.

Now, grab your RDA and feed the leads from one of your coils into one negative post and one positive post. If you’re using a 4 post RDA, you can go ahead and tighten down the screws once the coil is sitting above the deck, not touching the posts but also not hanging too far off the side. If you’re not using a four post RDA, you’ll have to wait till the other coil is installed before tightening the screws.

Once both of your coils are inserted and secured, use your drill bit or screwdriver to maneuver the coil towards the center of the atty. This helps the airflow hit the coil evenly, providing better flavor and clouds.

Now, once both coils are positioned, use your ohm reader to check the resistance. It might not show .3 ohms right now - that’s OK. Just make sure it’s not reading wildly low or high, as this can be indicative of a short. If you’re using a regulated mod you can check the resistance on the mod itself, but don’t fire until you’re sure it’s not shorted - just to be safe.

Now, assuming you have no shorts, put that sucker on your mod and get ready to mold these coils to perfection. Fire your mod so that the coils begin to glow. Ideally they’ll glow from the inside out evenly, but this almost never happens at first. Don’t worry! We can make it happen. Using your tweezers or pliers, pinch the coils while they’re still hot ( NOT WHILE YOU’RE FIRING YOUR MOD. NO POWER SHOULD BE RUNNING THROUGH THE COIL). Fire, pinch, fire, pinch. You shouldn’t pinch with enough force to collapse your coil, but it should start to even out and eventually glow from the inside out. Occasionally during this process, check to make sure the screws are still nicely tightened, as the heat from the coil can cause the screws to back out somewhat. If your coil still isn’t heating evenly from the inside out, brush or “strum” them with your screwdriver or tweezers. This helps relieve any spots where the wire is under more tension than the surrounding area. Keep it up until your coils glow evenly from the inside out. Both coils should heat up at the same rate and intensity.

Now that your coils are ready, it’s time to wick. I use japanese cotton, but you can use whatever your preferred material is. Get a strip of cotton roughly the same size as your coil, and roll up one end to make it easier to thread through. Pull the cotton through the coil. Make sure that it’s not too tight, though there should be a little resistance. If there’s no resistance when you pull your cotton through, try again with a slightly wider piece. Now, trim the ends of your wick so that they are just long enough to touch the deck. It doesn’t need to go everywhere on the deck, just long enough to wick what’s sitting in the well.

Now all you need to do is juice it up! Get your wicks nice and wet, and fire her up!

Don't worry if it tastes a little bit cottony at first, after a little bit it should clear up and all you'll taste is delicious e-liquid (maybe even ours). Hopefully this guide has helped you get your feet wet in the world of dripping. There’s a lot of stuff to explore, like fancy builds, and unique wicking techniques like the scottish roll. The only direction from here is up!
http://www.bombies.com/blog/building-your-first-rda-tutorial/