Trimming the wick and burning evenly

A candle burns evenly when the melt pool spreads to the edge of the top. Trimming the wick and the first burn decide whether this happens. Both steps are simple, but the faults they prevent are hard to correct once a candle has burned unevenly.

Steps

1. Let the candle burn for a short time, until the melt pool covers the top from the wick to the edge.
2. Put the flame out with a snuffer or a metal lid placed over it. Do not blow hard, since this spatters hot wax.
3. When the candle is cool, trim the wick to a few millimetres above the surface of the wax. Use a clean cut, not a pull.
4. Remove the blackened tip, and brush away any loose soot from the top of the candle.
5. Light the candle again and watch the pool. Let it spread to the edge before the flame is put out.

What can go wrong

• Tunnelling: the candle burns down the centre and leaves a ring of wax around the edge. Each later burn makes the ring deeper.
• Mushrooming: a ball of carbon forms on the wick tip, which gives smoke and a flickering flame.
• A long wick gives a high flame, smoke, and soot on the walls near the candle.
• A short wick drowns in its pool, and the flame goes out.

A candle is burning correctly when the flame is steady, the pool reaches the edge, and the smoke is light or absent.