It seems simple on the surface when you see a burning candle. It burns, it melts, and it gives out light. There’s actually more at play behind what looks like a relatively simple activity than many people realize. Physics, chemistry, and candle design all have a hand to play in the way your candle works as it burns. Knowing these things is key to the development of your candle design skills, as they explain the reasons behind well-performing and non-performing candles.
How Candles Burn
A candle doesn’t technically burn the wax. Rather, the candle flame warms the wax closest to the wick, liquefying it. This liquid wax is then absorbed into the wick due to capillary action. As the liquid wax is absorbed into the flame area, it turns to vapor and then burns. This cycle continues so long as the right wick-to-wax relationship is maintained. If the balance is wrong, you won’t get a properly functioning candle.
The Role of Wax
Wax isn’t just a solid material used to hold shape; it affects the burn rate, how stable your candle flame is, and even how well your candle performs fragrance-wise. Wax is solid at room temperature and can be melted down into liquid wax.
However, all waxes aren’t the same. Different waxes melt at various temperatures and act differently as they are warmed. Soft waxes melt quickly, but may tend to burn quicker than harder waxes, which might require more of a consideration of wick size. The waxes you work with can have a major impact on the rest of your candle.
The Importance of Wick Selection
The wick of your candle acts as the engine in the way your candle is functioning as it burns. It controls how much of the melted wax is absorbed into the wick and how evenly it burns. If the wick is too small, it won’t create a large enough flame to melt sufficient wax, and you risk a tunneling problem. If it’s too large, it may create a flame that’s too hot, produce smoke, or lead to issues with candle stability.
Different wicks also work differently depending on the candle design. Cotton wicks, wood wicks, and braided wicks all burn at different rates and create different patterns. Choosing your wick isn’t purely a technical consideration, it’s also a part of your overall design.
The Need for Balance in Candle Design
There’s always a delicate balance of candle components. The right wax, wick, and shape work together as a candle system. Changing one of the variables is likely going to affect the other two. That’s why candle design isn’t just done through luck but requires testing and modification. Every variable of a candle design affects the outcome, from things as small as container to even how much a room is heated at any given time. Candle designers must become familiar with this kind of interaction through experience.
A Part of Testing as Candle Design
Every candle must go through burn testing to be truly finished. This tells you how your candles will work over time rather than how they just look when they first start. The main considerations you’re testing for are the way the candle burns, whether or not there is proper melt pooling, how fragrance does as time passes, and whether you’ve got a residue in the final state of the candle that you like.
Burn tests are the bridge between candle design and candle creation. The theoretical design can only be fully verified in testing and testing. As such, iteration is essential for developing a candle as it should be.
Conclusion
Candles burn as a controlled system rather than randomly. Knowing how your wax, wick, and flame will work together gives you control over your candles in design. At this point, you’re able to develop candles based on intentional design rather than trial and error.