The Burn Test

One burn tells you nothing. Two burns tell you what you want to hear. Four burns tell you the truth. The 4-burn protocol is the smallest amount of evidence I trust before I sign a wick off for a range, and it is what every wholesaler I have ever pitched has asked to see.

The worksheet opposite is the exact template I use. One row per burn, five columns per row. If you cannot fill in a cell honestly, you have not run the test, you have watched a candle.

The five measurements

Duration, melt pool depth, mushroom size, flame height, and vessel temperature. Each one catches a different failure mode. Duration proves you honoured the one-hour-per-inch rule from Act 1. Melt pool depth tells you whether the wick is working the wax or overheating it. Mushroom size flags carbon build-up before it becomes soot. Flame height is the fastest read for over-wicking. Vessel temperature is your safety ceiling.

Aim for a melt pool between 8 mm and 12 mm deep by the end of burn three. Flame height 25 mm to 35 mm. Vessel temperature under 80°C at the glass, measured with the probe pressed flat against the outside near the melt line.

Reading mushrooms honestly

A small mushroom at the tip of the wick after a four-hour burn is normal. A mushroom the size of a pea after 90 minutes is not. Under-wicked candles mushroom because the flame cannot draw wax fast enough and starts eating the wick itself. Over-fragranced candles mushroom because the fragrance is thickening the melt pool. The mushroom reference card on this spread shows the four sizes I score against.

Between burns

Trim the wick to 5 mm while the wax is still warm. Wait at least four hours before the next burn so the candle returns to room temperature. If you burn again before it has fully reset, you are testing a hot candle, not a fresh one, and the melt pool will read wider than reality.

The wick that passes four burns in your kitchen is the wick that survives a customer's Sunday afternoon.