FAQ: Why does my candle have a rough, lumpy top?

In the majority of cases a lumpy top on a candle is the result of pour temperature. Many people do not place enough importance on pour temperature, some not even using a thermometer.
If you want a great looking soy candle with smooth tops and good glass adhesion, investing in a good quality thermometer is a must.

The weather is also an important factor in how your candle will set.  Many candle makers are caught by surprise, when after a couple of months of pouring, their candles all of a sudden develop holes or pits when they have changed nothing. They may not have changed anything but the weather may have changed. The season and your ambient temperature of the room you are pouring in, all play a big part in how your candle dries. You may use air conditioning in summer and a heater in winter. This will all affect your candles. On a particularly cold day you may also have to heat your glass or container slightly so it is warm to touch.

Lumpy tops can usually be fixed by increasing the pour temperature in increments until the problem disappears. The recommended pour temperature is a recommendation only and should be used as a guide for a starting point. If the recommended pour temp does not work you will have to experiment to find the correct temperature for your conditions and fragrance.

Fragrance and essential oils can also cause holes and lumpy tops. Fragrances like vanillas and essential oils such as lavenders and rose geranium are notorious for 'curdling' the top of soy candles. This can be overcome by pour temperature adjustment once again, however if this does not work, you may have to adjust the amount of FO or EO you are using.

It does come as a surprise to many, but pour temperature is absolutely critical for your candles and may change with the seasons. Extensive testing and a detailed diary is a must for all candlemakers!

Frequently Asked Questions

What actually causes a lumpy top on a soy candle?

In most cases it comes down to pour temperature. Many makers do not place enough importance on it, and some pour without a thermometer at all. If you want smooth tops and good glass adhesion, a good quality thermometer is essential.

How do I fix a lumpy or uneven top?

Lumpy tops can usually be corrected by increasing the pour temperature in small increments until the problem disappears. The recommended pour temperature is only a starting guide, so you may need to experiment to find what works for your conditions and fragrance.

Why did my candles suddenly develop pits when I changed nothing?

The weather most likely changed even if your process did not. The season and the ambient temperature of your pouring room play a big part in how a candle sets, and using air conditioning in summer or heating in winter will affect your results.

Can fragrance and essential oils cause lumpy tops?

Yes. Vanillas, along with essential oils such as lavender and rose geranium, are notorious for curdling the tops of soy candles. Adjusting your pour temperature usually helps, and if it does not, you may need to adjust the amount of oil you are using.

Should I warm my container before pouring?

On a particularly cold day, yes. Heating the glass slightly so it is warm to touch helps the wax set more evenly and adhere better to the container.