Terre de Bougies offers a complete range of professional equipment and raw materials for making candles at home. That said, candle making is a world full of technical details that you won’t always master straight away, so your finished candles may not turn out quite as you expected at first.
Have you made candles with soy wax or coconut wax and noticed a few problems? Is that normal? Don’t worry, we’re here to help. We’ve rounded up the most common issues you may come across when making plant-based wax candles. Follow our advice and you’ll see: no more nasty surprises, ever!
Why is my candle frosting?
Frosting is caused by tiny crystals growing on the surface of the wax. It’s perfectly normal, as all soy waxes frost over time, but fortunately it’s a purely cosmetic issue and doesn’t affect how your candle burns or smells.
Possible causes include too much oil in the wax or wax that cools too quickly.
Stir your melted wax more gently:
Stirring melted soy wax too vigorously can increase and/or speed up crystallisation, which creates that frosted look.
Preheat your glass containers:
Preheating your glass containers can help reduce how quickly and how much your soy wax candles frost. You can easily preheat glass containers in a warm oven set to its lowest temperature.
Make sure you don’t heat your containers above 40°C, and take care not to burn yourself when handling hot glass jars.
Lower your pouring temperature:
Pouring your wax at a lower temperature can help reduce crystal formation as it sets.
Let your poured candles cool more slowly:
Make sure your candles cool at room temperature (ideally 20 to 25°C) somewhere free from draughts. You can stand them on a cooling rack: they will cool more evenly than on a solid surface such as a table. Solid surfaces can also draw heat away from the bottom of the container and make the wax cool too quickly.
My candle has wet spots on the glass
What look like wet spots on the sides of candles in clear containers are actually areas where the wax has pulled away from the glass as it cooled, which gives that damp appearance. This happens because the wax cools faster in some parts of the container than in others: some of it comes away from the glass while the rest stays stuck to the sides. It’s the most common glass adhesion issue with poured candles. It doesn’t affect how your candle performs and can easily be hidden with a label.
To avoid wet spots in your next batch, try the steps below:
Clean and preheat your glass containers:
It’s always a good idea to wash your containers in mild soapy water, then dry them thoroughly before use. Preheat your jar in a warm oven at 35°C before pouring your wax, so that it cools more slowly and doesn’t pull away from the sides.
Pour your wax slowly:
Pouring your wax gently into your containers reduces the risk of adding air to it (which prevents even cooling). It also helps to tap the sides of your containers lightly just after pouring, to release any air bubbles that may have formed.
Space out your candles while they cool:
While your candles are cooling, leave about 10 cm or more between them. Glass containers placed side by side hold on to heat, so their sides cool more gradually than the rest of the container. Letting air circulate around your candles as they cool encourages even cooling.
You can also stand your candles on a cooling rack rather than a solid surface. Solid surfaces can draw heat away from the bottom of the container, making the wax cool too quickly, shrink and pull away from the glass.
The surface is rough…
It can be very frustrating to find a rough, not-so-pretty surface on your cooled candles. It’s a common sight when working with soy wax. As your poured candles cool, the wax naturally starts to form solid crystals. Ideally, these crystals are fine and uniform, giving the wax the smooth, creamy look soy is known for. But if the wax cools too quickly or too slowly, or contains tiny air bubbles, your candle is likely to end up with a rough finish.
Don’t worry, there are several things you can do to prevent and fix these imperfections:
Avoid over-stirring:
Stirring too vigorously can create air bubbles in your melted soy wax, which can lead to imperfections in your finished candles. If you notice air bubbles, gently tap the container just after pouring the soy wax to help them rise to the top and escape.
Adjust your pouring temperature:
Finding the perfect pouring temperature may take a little trial and error. Start by adjusting it up or down by 5°C. Once you’ve found the right temperature, your candles will cool more evenly, making imperfections less likely.
Cover the imperfection with a layer of wax:
When pouring your candles, especially if you’re a beginner or often get uneven results, it’s always a good idea to set aside some of your wax so you can remelt it and cover any imperfections once your candles have cooled. Top your candle with about 3 mm of melted wax to cover surface imperfections.
Remelt the surface with a heat gun:
Minor imperfections can easily be fixed with a hot air gun, also known as a heat gun, available in our shop. Set the heat gun to a low temperature and hold it fairly close to the container, over the flaw you want to fix. Let the soy wax melt slightly: this will smooth out most small surface imperfections.
My candle has cracks
It’s common to spot a very fine circular crack about 2.5 cm from the wick. It’s caused by the wax shrinking slightly as it cools, combined with tiny air bubbles trapped at the bottom of the container. Once the wax has set, it sinks a little where the air bubble left a gap. Don’t worry, it won’t affect how your candle burns.
Tap the container gently:
Gently tapping your container on your work surface helps release any air bubbles trapped in the wax. Of course, don’t tap too hard or your glass will break!
Raise your container off the surface:
While your candles cool, stand them on a cooling rack to lift them off the surface. Solid surfaces can draw heat from the bottom of the candle and make it cool too quickly. Better airflow underneath gives more even cooling.
Adjust your pouring temperature:
As with the previous problem, finding the right temperature will help your candles cool more evenly, making imperfections less likely.
Top up with extra hot wax:
Melt down your leftover wax, or the wax you set aside earlier. Slowly pour a layer about 3 mm thick over the top of your candle to fill the holes and cracks and create a smooth top.
If you’ve run out of leftover soy wax, you can use a heat gun to melt the surface and fill the cracks. It may take one or two passes to smooth the surface completely.
Why is my wax lumpy or damp?
Soy is a natural material that can vary slightly from one batch to the next. Sometimes you’ll get oily flakes that clump together; at other times they’ll be very dry. When the wax is lumpy or oily, it’s usually down to the outside temperature or a higher oil content in the wax.
There’s no need to worry: you can carry on with your usual candle-making routine as long as you follow this tip.
Heat the wax to 85°C:
If the clumping you notice in your wax is caused by excess moisture, heat it to 85–95°C and hold it at that temperature for 5 to 10 minutes to help the moisture evaporate.
Air bubbles in the wax
During production, the soybean oil that eventually becomes soy wax is constantly stirred and agitated, which lets air into the oil. Some of this air can become trapped in the wax during processing and is then released when you melt it to make candles.
If your wax contains too much air, you may notice a slightly foamy look and bubbles rising to the surface as the soy wax heats up. You may also hear a crackling sound, a bit like frying.
Let the air bubbles escape:
Stir the wax slowly to help release the trapped air. Keep going until the crackling stops and there are no more visible bubbles.
Be gentle when stirring or mixing your ingredients:
Stirring the wax too vigorously will create air bubbles, so stir gently to avoid adding extra air.
Heat your wax slowly to 85–95°C:
If you hear a lot of crackling, heat the wax to 85–95°C to release the trapped air.
Why is my candle wax cloudy?
As explained above, soybean oil is constantly stirred during production, which lets air into the oil. When you melt soy wax, it usually turns clear as it melts. Sometimes, however, you may notice the opposite: the wax turns cloudy, just as it does when it cools and sets after pouring. This is because air or water was trapped in the wax during production.
Let the wax heat to 85–95°C:
Holding the wax at 85–95°C will allow any trapped moisture to evaporate.
Give the wax time to breathe:
If the cloudiness is caused by trapped moisture, leave your bag of wax open rather than sealed so the moisture can evaporate.
Store your wax in a cool, dry place:
Storing your wax in a cool, dry place lets excess moisture evaporate and stops it building up in the bag.
Why is my wax discolouring?
Whether you colour your candles or leave them undyed, sooner or later they will be affected by natural and/or artificial light! Just as sunlight yellows white fabrics and fades bright colours, undyed candles will start to yellow and coloured wax will eventually fade. In fact, fragrances high in vanillin and many citrus scents can turn wax yellow within 24 hours, while fragrances containing small amounts of vanillin and floral scents can cause gradual yellowing over time.
Use a UV inhibitor:
Sunlight fades coloured candles. A UV inhibitor acts like a sunscreen for your candle, blocking UV light to prevent fading and yellowing. Note that yellowing caused by the vanillin in fragrances is a separate issue and won’t be solved by a UV inhibitor.
Add a small amount of ivory dye:
If your candle is yellowing because of the vanillin in your fragrances, use a small amount of ivory or cream candle dye to help neutralise the yellow tint and achieve a more natural, even soy colour.
Keep fragrances containing vanillin to a minimum:
Vanillin is known to discolour wax. If you find that a UV inhibitor or ivory dye isn’t doing enough, consider using fewer fragrances that contain vanillin.
Sinkholes in the wax
Air can become trapped in soy wax during production. When you melt it at home, you may sometimes see or hear some of this air escaping.
As the wax cools and hardens, the air works its way up to the top and is released. However, if the surface of the candle sets before the air has had time to escape, it gets trapped inside. When the wax sets, the air pocket leaves a void and the surface above it caves in. These sinkholes are sometimes tiny, but they can also be as much as 2 cm deep.
Top up with more melted wax:
Reheat your leftover wax, or the wax you set aside for this purpose. Then slowly pour it over the top of your candle in a layer thick enough to fill the holes and create a smooth top.
Melt the surface:
If you’ve run out of leftover wax, you can use a heat gun to melt the surface and fill the holes. It may take one or two passes to smooth the surface completely.
Check the wax and get rid of existing air bubbles:
Keep an eye on the wax as it melts to spot any visible air bubbles, and stir gently to bring them to the surface. After pouring, tap the container carefully on your work surface to release any trapped air.
Pour at a lower temperature and warm your containers:
Lower your pouring temperature: the lower the temperature, the less the wax shrinks. Preheating your containers can also reduce shrinkage.
Conclusion
You now know all about the potential problems you may face when making soy wax candles. Feel free to get in touch with us or tell us about any other issue not covered in this article. In the meantime, discover vegetable stearin and its lesser-known uses.
