Why does the wick in my candle matter?
Pretty much every store sells candles. Discount stores, grocery stores, specialty stores – they are everywhere! If you’re like me, you can’t help but stop and smell all the different candles when you are out shopping, especially if they have interesting scent combinations. You read the name, look at the color, sniff, and decide if you like it enough to add it to your growing collection of candles. But have you ever really looked at the most important part of a candle – the wick?
Wicks are what allow the candle to burn. They are typically made of braided cotton and may have a light coating of wax on the outside. Most wicks have a thin piece of zinc or tin wire inside to act as a stiffener so they don’t fall over. Candle wicks do not contain lead! The US banned the manufacturing, importing, and selling of lead-wicked candles almost 20 years ago. Wicks can also be made out of tightly woven paper fibers or even wood strips. Lighting the wick causes the wax around it to melt, which becomes the fuel that keeps the candle burning. The wick acts kind of like a spongy straw, soaking in the melted wax so it can travel upwards to the flame.
So why doesn’t the wick burn up? Because the liquid wax that surrounds it burns first and essentially protects the wick. Have you ever seen chefs on cooking shows use alcohol to set a pan on fire?
The food doesn’t get burned to a crisp, despite all those flames on it, because it’s the alcohol on the surface that is actually burning. It’s a similar thing with candles. The wick IS burning, since it gets shorter over time, it just doesn’t burn as fast as the melted wax does.
So don’t all wicks do the same thing? Mostly, but it’s more complicated than that. Wicks come in a lot of different sizes. The length needed depends on how deep the container is. The thickness of the wick is important too and is based on the diameter of the finished candle. Think about a tea light compared to a big jar candle. The type of wax (paraffin, soy, beeswax, etc) also matters, but that’s getting way too technical!
PRO TIP: If the candle has only 1 wick, compare its thickness to the diameter of the container. If it looks really skinny and small, put that candle back on the shelf and walk away!
At some point, you’ve probably had a candle that just burned straight down the middle, leaving a lot of wax around the outside. This is called tunneling and it’s caused by having a wick that is too small for that container size. This creates a very inefficient candle, since about half the wax never melts! Now, with free-standing pillar candles, this can be a good thing. Tunneling keeps the edges of a pillar candle from melting and spilling the wax down the sides, so there are less drips and mess.
PRO TIP: To be safe, you should always burn a pillar candle in some type of dish or container to catch any drips and to keep it from falling over and setting a fire.
So why not just use the bigger wicks? Because a wick that is too large for the container can create a dangerously large flame that makes a lot of black soot and smoke and can even crack the glass container if it gets too hot! We saw that happen during wick testing for our Botanical Collection. The wick we used was too large, so the candle burned too fast, the glass got too hot, and the container shattered. Wick testing allows candlemakers to know they are using the proper sized wick for each container.
PRO TIP: This is also why you don’t want to try to burn every last drop of wax in your candle. Always leave about ¼” of wax unburned.
It’s not always possible to find a wick that can burn efficiently and safely in a larger container. That’s why some candles have 2 or 3 wicks, which we will look at in Part 2.