For beginners and more advanced candlemakers alike (even though they won't always admit it), the most confusing and difficult aspect of candlemaking is the choice of the right type and size of wick!
And indeed, the correct burning behavior of your candles will depend for more than 90% on the correct wick choice: too small a wick and the melting pool will be too narrow, the flame will bore a hole through the middle of the candle (called tunneling) and leave most of the wax intact. The flame might even die out due to a lack of oxygen or be put off by too much liquid paraffin.
Too thick a wick and it will produce smoke, mushrooming and generally melt the wax too quickly...
Without a wick, a candle would be nothing more than a block of paraffin. Scented perhaps, colored undoubtedly, decorative possibly but still, just a block of paraffin.To bring it to life, you'll have to give it a wick.
Nowadays, most candle wicks are made of braided cotton threads.
Historically, one of the most popular wick types has always been the flat braid.
It's used mainly in taper candles, those long, thin candles created by repeatedly dipping wicks in a pot full of melted paraffin.
Flat braid wicks are also used for pillar candles.
Its big sister is the square braid wick.
The square braid is almost identical to the flat braid except it's braided in such a way that its section is square instead of flat, which allows it to stand up straight in the candle's melt pool. It's used primarily in pillars and is also the recommended wick when using beeswax.
In certain types of candles, especially container candles where the proportion of melted wax can be important, it is crucial that the wick stands up straight so that it would not fall into the melt pool and die out. To achieve such rigidity, we use cored wicks. They have either a zinc, a paper or a cotton core around which the cotton threads are braided.The core not only provides the required stiffness, it can also (depending on the type) make the flame burn hotter.
Cored wicks must be centered at the bottom of the container before the wax is poured. To make this possible, the wick is attached to a round piece of metal called a wick sustainer tab that gets glued in place at the bottom of the container, either with a small amount of melted wax, a glue gun or glue dots.
The family of wicks we will explore next are based on the same principle.
There are dozens upon dozens of variations on the previous three types of wicks and each variation is a better fit for a specific type of candle or type a wax than another. Together, these variations form the extended family of specialized wicks (to name but a few, meet the RRD, TCR, CD, ECO, HTP or LX series of wicks). They will be the topic of their own article where I explain their characteristics and the recommended usage for each series of wicks.
Recently, a new type of candle wick has become increasingly popular: the wooden wick.
Used almost exclusively in container candles, made of soywax or paraffin wax, a wooden wick is made of one or two very thin strips of wood (different essences are used but cherry seems to work well) pressed together and treated with a secret blend of additives to ensure an even combustion.
When it burns, a wooden wick crackles like a tiny wood fire and smells just like one too.
An important notion when wicks are discussed is their burn rate, in other words how much wax a wick can consume in a given time. The burn rate is expressed in grams per minute.
This is an interesting data because people will usually choose (and buy) the longest lasting candle they can find. Here again, experimentation will teach you a lot. For example, the burn rate will go up or down whenever you use another wax formula and/or another type of wick.
To calculate the burn rate of a wax / wick combination, start by weighing your candle and write its weight down. Example: 420 grams.
Light the candle and let it burn for exactly one hour. When done, blow it off and weigh it again, including any wax that may have dripped. Example: 350 grams.
The wax consumption is thus 420 - 350 = 70 grams in one hour, which means 70 / 60 = 1.16 grams per minute.
We can say that this particular wax / wick combo has a burn rate of 1.16