It’s a very underrated and extremely misunderstood, but highly important piece of candle equipment.
The humble wick tab plays a really important role in the safety of your candles.
If you have ever taken the time to actually look at and compare your wicks, you would have noticed the wick tab changes size depending on the size of your wick.
At ACS we use three main sizes - 15mm x 3mm neck, 20mm x 3mm neck and a 20mm with a 6mm neck.
It’s really the neck size we want to focus on.
Tabs are designed not only to hold your wick in the bottom of your jar, but also to stop your candle from burning to the very bottom of the glass.
When performing correctly, the wick tab will
stop the wick from burning once the flame reaches the neck, leaving a couple of mm of wax in the bottom of the glass.
The size of the neck will determine how much wax will be left. The bigger the jar and wick, the taller the wick tab neck needs to be.
Over the years we have had many queries, complaints and questions on how to stop wicks from burning out before they have used all of the wax in the bottom. Customers saw it as a waste of candle product.
It is however a massive safety feature. Burning your candle all the way to the bottom can be very dangerous and can cause the glass to super heat and crack or even explode. The little amount of fuel left in the bottom of a candle becomes hot enough to vaporize and will no longer need a wick to burn. This phenomenon is called ‘flashover’. This super heated fire is what can and does cause candle glass to crack or explode violently.
Next time you test burn your candle do some temperature measurements on the glass and the melt pool when it’s nearing the bottom. It is so so hot.
Sometimes the wick tab does it’s job but sometimes it doesn’t.
Customer education should include extinguishing candles before they burn completely, leaving at least 1cm of wax at the bottom.
Back before pre-tabbed wicks (in the olden days) 😱😂 we used to tab just about all of our wicks we were using in candles with a 6 mm tab just to be sure.
As a guide, Tealight wicks usually have a very small tab 15 x 3mm. Smaller candle wicks up to Acs 4.0/4.5 or cdn 10 will have a 3mm neck and the rest a 6 mm neck.
When purchasing your wicks make sure it has an appropriate tab size to fit the wick size and make sure you educate yourself and your customers on this little known but very important candle burning fact.