Candle Tunneling: what it is, how to fix it and preventing it

Candle Tunneling: what it is, how to fix it and preventing it

What is candle tunneling?


It is quite possible that during the process of making candles, you have come across an instance where your candle failed to burn evenly, creating a ring-shaped 'tunnel' that extended from the wick to the candle's core. 


We call this incredibly frequent occurrence "tunneling." Whether you're burning a highly expensive or a cheap corner store candle, all candles have the ability to tunnel.


Candle tunneling, although unappealing and resulting in wasted unburned wax, is rather common and preventable with proper candle care. 


What are common causes of candle tunneling?


The section that follows highlights a few of the most frequent causes of candle tunneling. Knowing the reason behind your candle tunneling will help you avoid it in the future.


  • Irregular burning practices: Candles should always burn for long enough so that the wax pool has enough time to reach the edges of the candle vessel. Extinguishing a candle too early may lead to the formation of a tunnel.
  • Incorrect wick size: Using a wick that is too small for the amount of wax or the width of your vessel is a frequent cause of tunneling. Even with the best of intentions, a wick that is too small could not have the power to burn the wax all the way through.
  • Unsuitable wax blend: An often-overlooked element as a cause for candle tunneling is the type of wax used in the creation of the candle. Some waxes have been developed to be intentionally 'harder' meaning it has a higher melting point, making it more suitable for warmer climates, pillar candles or melts. On the other hand, certain blends of wax are noticeably 'softer' making it more appropriate for container candles and cooler climates.
    It's crucial when choosing your wax, you choose one 'fit for purpose' to try and prevent issues like tunneling.

How to fix a tunneling candle

There are several methods for fixing a tunneled candle, such as blasting the edges with a heat gun to remove any remaining wax, but our favorite is the method with tin foil.

In essence, you may use tin foil to form a dome around the top of the container candle. This will reflect heat back onto the unburned wax, allowing it to melt and combine with the pool of wax that has already begun to melt.


How to prevent candle tunneling

We've covered what candle tunneling is, its causes, and how to solve it; but, as they say, prevention is always preferable to treatment. When creating candles, always take the following precautions to avoid candle tunneling:


  1. Make sure the wick you're using fits within the dimensions of your jar (always test!)
  2. Choose the right kind of wax depending on the kind of candle you're crafting. 
  3. Avoid packing too much thick, sticky fragrance oil into your candle as this may make it more difficult for the wax to burn through.

When on-selling your candles, always mention to your customer to burn the candle from edge-to-edge. Perhaps you can add a label or a little note with burning instructions. When you shop with SoulKey Co, all of your candle care instructions are specific to letting your candle burn for 3-4 hours for the first burn to avoid tunneling. You can always refer to our instagram pinned post about candle care!

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