WHY DOES TUNNELING HAPPEN?

People sometimes mistake tunneling as an issue of candle quality.

It’s true that tunneling is more likely to occur in cheap candles compared to higher quality luxury candles. However, the truth is that tunneling can happen to ANY candle — even the most expensive ones.

It’s important to burn the candle long enough to let the entire surface of the candle melt before blowing or snuffing it out. This usually takes at least an hour or two, depending on the size of the candle.

If you don’t do this, you’re almost guaranteed to get tunneling.

Why? That’s because wax contains a certain amount of “memory.”

Wax isn’t always as “hard” as it seems. Even in its solid, unmelted state, wax will continue to harden over time. Candle wax that was melted and cooled again yesterday will always be softer than candle wax that has been sitting around for a week.

So If, on the first time, you only let the wax in the center melt before blowing the candle out, on the second time you burn it, only that small center portion of wax will continue to melt. That’s because it’s “softer” than the wax around it and therefore requires less thermal energy to melt again. The surrounding wax that didn’t melt the first time is “harder” in comparison, so it won’t melt and voila — you have tunneling.

To prevent tunneling, all you need to do is burn your candle long enough each time so that the entire top surface of wax is melted. This is especially important the first time you burn your candle!

How long that takes depends mostly on the size of the candle. A good rule of thumb to remember is that you should burn your candle for one hour per every inch of its diameter. So if your candle has a diameter of 3 inches, you should plan to let it burn for 3 hours before putting it out.

HOW TO FIX CANDLE TUNNELING

What should you do if your candle has already started tunneling?

Conceptually speaking, in order to fix candle tunneling, all you need to do is melt the outer wax surrounding the tunnel and make the surface even again.

If the tunneling is severe (i.e. the sinkhole is 1-2 inches deep), it may be difficult to salvage. You might need to spend a lot of time to melt down and remove the extra wax.

But if the sinkhole is still pretty shallow (ideally 1/2 inch or less), you can fix the tunneling without too much trouble.

OPTION 1: THE HAIR DRYER METHOD

For this method, we use an external heat source (a heat gun is ideal, but a hair dryer can also work) to melt the harden wax around the edges of the container. This "resets the memory" of the wax, so to speak, widening the melt pool that reaches all the way to the edges.

For your safety, especially if you're doing this for the first time, make sure you're wearing eye protection and clothes that can be washed if a bit of wax gets on it. And lay some old newspaper beneath the candle to protect your table or floor.

Lastly, when using your hair dryer, don't turn it on directly over the candle — hold it far away and slowly move it closer to an appropriate distance where it won't be blowing melted wax all over the place.

Trim the wick and remove any debris inside the tunnel.
Using a heat gun (if you have one) or hair dryer (on low speed & high heat settings), gently heat the top surface of the candle from an appropriate distance.
You can carefully scrape at the unmelted wax on the sides with a wick dipper or small metal spatula to help it melt faster.
Continue heating until the entire top surface of wax has completely melted and smoothed over. This may take several minutes depending on how hot your hair dryer gets, so prepare to be patient.
Relight your candle and allow it to burn for at least 30 minutes or until you can no longer see any tunneling.
Set your candle aside and let the wax harden over the next few days. 2 weeks for soy wax to reach full hardness.

OPTION 2: THE ALUMINUM FOIL METHOD

Rather than using an external heat source, this method traps and reflects the candle's own heat to achieve the same effect of melting the extra wax and smoothing over the top layer.

Like with the method above, please put safety first whenever you're dealing with lit candles and hot wax. The candle container WILL get very hot.

Trim the wick and remove any debris inside the tunnel.
Cover the top of the candle with aluminum foil.
Cut or fold a small opening (around 1-inch) in the center of the aluminum foil.
Remove the aluminum foil, light the wick, then place the foil cover back on.*
Allow the candle to burn for a few hours until the top surface of wax has completely melted and smoothed over.
Set your candle aside and let the wax harden over the next few days to reach full hardness (see above).

*Note: If your flame goes out put the foil on, that means the opening you cut in step 3 might be too small for your candle. Widen the hole a little bit and try again until your flame stays lit.

And that's it! I hope this guide to fixing and preventing candle tunneling will help you enjoy candles that last longer and burn more beautifully.

Candle Tunneling: About

WHY DOES TUNNELING HAPPEN?

People sometimes mistake tunneling as an issue of candle quality.

It’s true that tunneling is more likely to occur in cheap candles compared to higher quality luxury candles. However, the truth is that tunneling can happen to ANY candle — even the most expensive ones.

It’s important to burn the candle long enough to let the entire surface of the candle melt before blowing or snuffing it out. This usually takes at least an hour or two, depending on the size of the candle.

If you don’t do this, you’re almost guaranteed to get tunneling.

Why? That’s because wax contains a certain amount of “memory.”

Wax isn’t always as “hard” as it seems. Even in its solid, unmelted state, wax will continue to harden over time. Candle wax that was melted and cooled again yesterday will always be softer than candle wax that has been sitting around for a week.

To prevent tunneling, all you need to do is burn your candle long enough each time so that the entire top surface of wax is melted. This is especially important the first time you burn your candle!

How long that takes depends mostly on the size of the candle. A good rule of thumb to remember is that you should burn your candle for one hour per every inch of its diameter. So if your candle has a diameter of 3 inches, you should plan to let it burn for 3 hours before putting it out.

HOW TO FIX CANDLE TUNNELING

What should you do if your candle has already started tunneling?

Conceptually speaking, in order to fix candle tunneling, all you need to do is melt the outer wax surrounding the tunnel and make the surface even again.

If the tunneling is severe (i.e. the sinkhole is 1-2 inches deep), it may be difficult to salvage. You might need to spend a lot of time to melt down and remove the extra wax.

But if the sinkhole is still pretty shallow (ideally 1/2 inch or less), you can fix the tunneling without too much trouble.

OPTION 1: THE HAIR DRYER METHOD

For this method, we use an external heat source (a heat gun is ideal, but a hair dryer can also work) to melt the harden wax around the edges of the container. This "resets the memory" of the wax, so to speak, widening the melt pool that reaches all the way to the edges.

For your safety, especially if you're doing this for the first time, make sure you're wearing eye protection and clothes that can be washed if a bit of wax gets on it. And lay some old newspaper beneath the candle to protect your table or floor.

Lastly, when using your hair dryer, don't turn it on directly over the candle — hold it far away and slowly move it closer to an appropriate distance where it won't be blowing melted wax all over the place.

Trim the wick and remove any debris inside the tunnel.

Using a heat gun (if you have one) or hair dryer (on low speed & high heat settings), gently heat the top surface of the candle from an appropriate distance.

You can carefully scrape at the unmelted wax on the sides with a wick dipper or small metal spatula to help it melt faster.

Continue heating until the entire top surface of wax has completely melted and smoothed over. This may take several minutes depending on how hot your hair dryer gets, so prepare to be patient.

Relight your candle and allow it to burn for at least 30 minutes or until you can no longer see any tunneling.

Set your candle aside and let the wax harden over the next few days. 2 weeks for soy wax to reach full hardness.

OPTION 2: THE ALUMINUM FOIL METHOD

Rather than using an external heat source, this method traps and reflects the candle's own heat to achieve the same effect of melting the extra wax and smoothing over the top layer.

Like with the method above, please put safety first whenever you're dealing with lit candles and hot wax. The candle container WILL get very hot.

Trim the wick and remove any debris inside the tunnel.

Cover the top of the candle with aluminum foil.

Cut or fold a small opening (around 1-inch) in the center of the aluminum foil.

Remove the aluminum foil, light the wick, then place the foil cover back on.*

Allow the candle to burn for a few hours until the top surface of wax has completely melted and smoothed over.

Set your candle aside and let the wax harden over the next few days to reach full hardness (see above).

*Note: If your flame goes out put the foil on, that means the opening you cut in step 3 might be too small for your candle. Widen the hole a little bit and try again until your flame stays lit.

And that's it! I hope this guide to fixing and preventing candle tunneling will help you enjoy candles that last longer and burn more beautifully.