Soy Wax Tunneling

Have you ever noticed a candle burning down the center, leaving walls of unburned wax on the sides? This is called "tunneling," and it can happen with soy candles if they’re not made or burned properly. Let’s talk about what causes tunneling and how you can avoid it.

What Is Tunneling?
Tunneling in a soy wax candle happens when the wax melts only down the center of the candle, leaving a ring of not yet melted wax around the edges. This creates a "tunnel" in the candle, which can waste wax and affect the candle’s overall burn. Here’s why it happens and how you can prevent it:

Improper Wick Size or Placement
If the wick is too small for the size of the candle, or off-center, it may not generate enough heat to melt the wax evenly, which can lead to tunneling. This often happens when the wick isn’t properly sized for the candle’s diameter. At Crum Canoe Candle Co., we carefully test and refine our wick sizes through trial and error to ensure they’re perfectly matched to your candle’s diameter and burn requirements. In our experienced opinion, wicking is the most challenging aspect of candle making, and we take it very seriously to ensure the best possible burn every time.

Insufficient Burn Time on the First Use
One of the most common causes of tunneling is not an error during the making, but user error. It is when the user does not allow the candle to burn long enough on its first use. We cast no judgment; we are these users on occasion too. Life happens. However, soy wax has "memory," meaning it will burn to the extent it did during the first session. If you extinguish the candle before the entire surface melts because life happened (i.e., the wax pool reaches the edges), the candle will "remember" this and may continue burning only down the center in subsequent uses, creating tunneling.
Prevention Tip: On the first burn, let the candle burn for 3-4 hours or until the wax has melted all the way to the edges. This will establish a full melt pool and prevent tunneling in the future.

Drafts or Airflow
Candles burned in areas with drafts (like near vents, open windows, or fans) can cause uneven burning. The flame might flicker, causing the wax to melt unevenly and leading to tunneling.
Prevention Tip: Keep your candles in a stable, draft-free location. If possible, avoid burning them in places where wind or airflow might interfere with the burn.

Temperature Fluctuations
Extreme temperature changes, especially in rooms that are too hot or cold, can affect how the wax melts and contribute to tunneling. If the wax is too hard from being kept in a cold space, it may not melt evenly. 
Prevention Tip: Store soy wax candles in a moderate, temperature-controlled environment to help ensure an even burn.


Now that we've covered what tunneling is, why it happens, and how to prevent it, let's talk about what to do if it’s already occurred. Keep diving in to find out how to fix it and get your candle burning evenly again! Here are a few ways to fix your tunneling candle so you can get your candle burning evenly again: