As a candle burns down vertically it will burn further out horizontally. When the candle is about 1″ down the flame will start to melt more of the “hang-up” on the sides of the candle. As the candle burns down and the flame nears the bottom of the candle the trapped heat is the greatest.
We use about 6 different types of wick and many different sizes. In all we have about 20 – 24 jars burning at a time. That is 10-12 (wax, wick, scent,) jars with a duplicate.
Candle makers often talk about test burning candles. It seems like common sense that a candle maker who sells a product would know how their candles burn. A lot of candle makers have different ideas about test burning.
Burn multiple candles with the same wick.-Another important component of testing is to make sure that you can duplicate your results. You may get an unreliable burn if the wick was not primed correctly, something got into your candle, the wick incorrectly labeled, braiding tension was faulty, etc. Thus, if you have two or more of the same wick/wax/scent/ dye combinations and they are burning the same you can be more assured of the accuracy of your results.
It seems like common sense that a candle maker who sells a product would know how their candles burn. A candle that seems to burn well at the beginning of its life could become a flamethrower as the wick nears the bottom of the candle. As the candle burns down and the flame nears the bottom of the candle the trapped heat is the greatest. You don’t want your candle to burn all of the way out to the edge until the candle is about 1″ down. When the candle has reached it’s full burn time (2 hours for a 2 inch diameter, 3 hours for a 3 inch diameter candle) in zone two it will leave very little wax on the edges.
If you plan on selling a product you should know that product! Here are some things to consider when test burning candles.
In the first zone the candle should feel warm on the top portion and should burn out to within 3/4″ – 1″ from the edge within it’s given time period. When the candle reaches the second zone the top wax “hang up” will start to melt. When the candle has reached it’s full burn time (2 hours for a 2 inch diameter, 3 hours for a 3 inch diameter candle) in zone two it will leave very little wax on the edges.
When you test 5 different wicks from different wick families that are supposed to perform well in the same wax and burn the same diameter they will not perform the same. Different families of wick burn better in different wax/scent/dye combinations.
Make sure that you burn all of the candles at the same time. You will be able to see how each is doing compared to the others throughout the entire test. Remember not to put the candles too close to one another or their heats may affect each other.
The following details are for how a container Scented candles candle should burn. Pillar candles burn the same after the first inch. Whereas container candle have different burn zones.
When you have an entire line of candles it is usually not a good idea to try and use just one size or type of wick. Braiding tension, type of material used, possible inner core or flame retardant treatment all contribute to the burning properties of the wick. When testing choose many wick families that you think will work best with your candle and go from there.
After you have actually picked wicks, wax, ingredients as well as scent it is time to begin screening.
Just because two different waxes are 100% soy does not mean that they will burn the same, have the same scent throw abilities or even the same dying abilities. Now can you see burning either one of them? Some waxes will be easier to burn then others.
A three-inch diameter candle should take about 3 hours to burn as far as it is going to burn. The burning diameter will expand as the candle burns down. You don’t want your candle to burn all of the way out to the edge until the candle is about 1″ down.
When testing you will want to hold them constant as you test for wick size. Sometimes using too much scent can “lock up” the scent or change the scent as it is burning. Filler is cheap and will often be used in inexpensive scents to keep the price of a pound of wax low.
Simply put, the test burn is used to understand how a candle burns. A candle that seems to burn well at the beginning of its life could become a flamethrower as the wick nears the bottom of the candle. It is also important to understand, as the candle burns down the diameter burns out.