What Causes Candles To Crack? Is It Dangerous?

You might be searching this topic as an avid candle lover who is despairing at cracking candles. Or, maybe you are a candle maker and you want to understand why your wax is cracking. What is going on? Of course, there is also the worry of wondering whether a cracked candle is still safe to use. There are ample reasons for candles to crack so let us get straight into this topic and look at prevention, too.

Candles can crack for a plethora of reasons but none of them offer any immediate danger. Most commonly, it is caused by imperfections in the design and there are tiny air bubbles that can cause crackling. It is dangerous if it is the glass that is cracked and this should be discarded immediately.

Why did my Candle just Crack? Top 6 Reasons

Let us begin by taking you through the 6 most common reasons for your candle to crack. You can then try and work out where you have gone wrong.

1.    Your stirring was a little too enthusiastic

While stirring the melted wax, it is essential to do this gently. Stirring it with too much gusto will create problematic air bubbles. Instead, stir your wax slowly and lightly without being tempted to speed up the process.

2.    Water has made its way into the wax

Unwanted water inside a candle can be a pain and will affect the burn time. It can also create an uneven cavity to appear. Ideally, any candles you suspect of containing water should be drained or not sold.

3.    The cooling process was too fast

The cooling process is a very important part of achieving a flawless candle. Never be tempted to speed this process up by sticking them in the fridge. Ideally, candles should be cooled at a room temperature of around 18℃.

4.    The container was too cold

Pouring your wax into a cold container can cause candles to crack. Warming it up a little before you get to this stage can help prevent cracks or holes from appearing in the wax as it cools.

5.    Your environment is humid

If humidity is high where you make your candles, then this can account for air bubbles getting into the candles. You can prevent this by popping a dehumidifier nearby.

6.    The temperature is wrong at the time of pouring

It will help to have the correct temperature for pouring. Too hot or too cold will cause cracks to appear. The ideal temperature to pour the wax into the container is between 120℉ and 165℉. This may vary depending on the room temperature and also how warm the container is.

Are Candles supposed to Crackle?

There are a few reasons your candles might be crackling. Let’s tackle each of these common reasons.

  • You might have purchased a candle with a wooden wick. Wooden wick candles are popular because of their crackling sounds. So, check your wick first. You can read more about them in our article; Wooden Candle Wicks – A Crackling Choice.
  • The candle may have uneven parts in it or even tiny holes. This can cause crackling sounds as the air bubbles pop with the heat.
  • Unsuitable wick size. You might have a wick that is too long and needs trimming. Or you might have failed to care for the wick after each burn, causing it to mushroom. This build-up of carbon can cause the flame to burn erratically.
  • Sometimes, something may have gone wrong during the candle-making process. In this situation, there is not a lot you can do except ask for a refund.
  • Excess moisture can cause your candle to crackle. Humidity or a room with excess moisture can contribute to this. Try moving your candle to see if this helps.
  • It might be something simple such as dirt or dust collecting on the candle’s surface. Once the candle has cooled, give it a quick clean and then pop a cover over it.

Why did my Candle Crack when cooled?

You may have followed the instructions for making your candle to a T, so why has your candle cracked during the cooling process? This can often be a direct result of the wax you have chosen to use. Beeswax, in particular, can be met with this problem. When the wax pool starts to cool down, it shrinks which can cause cracking. This is more so the case if the candle has been cooled down quickly.

It could also be that there were some impurities inside the candle that caused air bubbles to form. The other main reason is being short on time and trying to rush the cooling process. Despite what you may read, never put candles in the fridge or freezer to cool them quickly. There are no shortcuts to cooling them down and attempting to do so can result in a faulty candle being sold.

How do you stop Candles from Cracking?

We’ve covered the possible reasons for candles to be cracking but let’s talk a little more about prevention now. There are things you can do to stop candles from cracking. This is good news as no one wants to buy damaged candles.

  • You can preheat your candle molds. This helps ensure the cooling process is nice and slow.
  • Keep the room you are working in at a steady 64℉ and 68℉ anytime you are making candles.
  • It is acceptable to use a heat gun for any small surface imperfections. This can be enough to heal any visible cracks.
  • Slow and steady are key throughout the process. This includes the pouring and stirring steps. Pouring too quickly or stirring too hard can cause issues.
  • Beeswax candles are more prone to cracking. In most cases, however, the burning process will fill any holes when the wax liquefies.

Can you Light a Candle with a Crack in It?

You may have put off burning your candle as you’ve noticed there is a crack in it. You may even be worried it is unsafe to use. There are different answers to this, depending if we are talking about the candle itself, or the glass container.

Let’s start with cracks in the wax. Burning a candle with cracked wax can be a little annoying as it can cause an irregular burn. However, it is not unsafe to do so. There might be some noise such as crackling but the hot wax will even out any small imperfections.

On the flip side though, you should never burn a candle that has a cracked glass container. This weakens the glass and it is more prone to smashing under the heat. Also though, the hot wax can escape through the tiniest of cracks and end up on your furniture. This can prove very tricky to scrape off as it sets pretty fast.

You also run the risk of something called a candle jar explosion. This is when the intense heat from a burning candle puts too much pressure on the damaged glass. This can be severe enough to cause a serious fire or injury to those in its vicinity.

It can be frustrating to throw away a perfectly good candle due to a damaged container. More so if you haven’t yet lit the candle at all. Don’t fret though, you have a few options. You can ask for a refund or replacement if the breakage happened in transit. Or, you can pop the candle in the freezer, and then the wax will fall out. You can then reuse it in another suitable container.