How To Choose A Candle Wick

Published by Kevin Fischer on

With the exception of wax melts, every candle needs a wick.

It’s really not a candle without one, but where do you start? The only way to really know if you have the right wick size is through testing, but you can use this step-by-step guide to get started on the right track.

If you’re making taper candles or small votives, parts of this process may not apply.

Most of this guide targets container and pillar candles (and your acceptance criteria may vary depending on your intended outcome).

The selection process (and this guide) usually goes something like this:

  1. Pick a wax type
  2. Use the Wick Series Selection Table to find a wick series to start with
  3. Measure your candle diameter
  4. Use the Wick Size Selection Table to find three wicks to start with
  5. Design your candle (fragrance, dye)
  6. Test the candles
  7. Choose the best wick OR make adjustments

Wicks play an enormous role in the candle.

The market offers so many different wick types to compliment the variety of waxes, containers, and fragrances.

Why Wick Type Matters

Not every wick pairs well with every wax.

Commercial wicks (which you buy from a supplier) have a few notable traits that make them good or bad for specific waxes:

  • Fiber or thread makeup. A lot of wicks are cotton, but you can also find wicks made from wood, fiberglass, or “natural fibers”.
  • Braid design. Most wicks have threads that are woven in a specific pattern or density, which impacts the burn behavior and temperature of the wick.
  • Wax coating. Commercial wicks have a coating of a high melt point wax, commonly paraffin, to add structure (stand up straight in a melt pool) and make it easier to light. Some wicks come without any of this, and some candle makers intentionally “prime” their wicks by dipping them in melted wax, though this isn’t a requirement either.

The reason these factors matter is each wax has different properties, such as density, melt point, and viscosity (whether it flows like water or molasses).

They come together when the wax melts and has to travel up through the wick.

How that wick is built determines how easily, and how much, of the melted wax moves through the wick over time.

Wicks that can’t handle the wax will improperly balance the combustion of the candle, leading to excessive heat, smoking, or even self-extinguishing (if enough wax can’t make it to the flame).

Step 1: Pick a wax type

The candle market is full of different waxes! Everything from vegetable wax, like soy or palm, to traditional wax like paraffin or beeswax.

They all come with pros and cons, so picking the right wax depends on your application.

Wax manufacturers typically design their wax for a specific application, so make sure you’re selecting one that’s appropriate for your candle.

The list below includes a few of the most popular wax blends for container candles of each wax type, but you can seek different suppliers for anything you want, especially if you aren’t making container candles.

Soy Wax

  • NatureWax C-3
  • Golden Brands 464

Paraffin Wax

Palm Wax

  • IGI R2332A

Paraffin-Soy Blends

  • IGI 6006
  • ProBlend 600

Wax selection plays one of the largest roles in your wick type because liquid wax (as the fuel) transports through the wick into the flame.

Step 2: Choose a wick series (or two)

Generally speaking, wicks work well in one set of waxes but not others.

You’re going to pick a series to start with, but might change your mind later.

Why?

Factors that change the burn behavior, that is fragrance oil, dye, and container, can react negatively to a wick commonly known to be okay for a wax type.

That is to say, if you choose to use CD for NatureWax C-3 soy, it might be okay for some designs but not others.

Wick selection is merely a starting point.

It’s a place to gather data for you to react to. The best candle makers know this, and usually won’t fret over their first few choices in wicks; every design has differences.

The following table isn’t exhaustive, but may help if you’re using an included wax or similar:

Wax Name Wick 1 Wick 2
Golden Brand 464 CD ECO
Golden Brands 444 CD ECO
Golden Brands 415 CD ECO
Cargill Naturewax C-1 HTP ECO
Cargill Naturewax C-3 CD ECO
Cargill Naturewax C-6 ECO CD
IGI 6006 LX CD
IGI 6046 ECO CD
IGI 4625 LX zinc
IGI 4630 LX CD
IGI 4627 CD LX
IGI R2332A CSN CD
ProBlend 600 ECO zinc
Coco Apricot Créme ECO LX
Beeswax Coco Créme ECO CD
Virgin Coconut Soy ECO CD

 

At this stage, select one or more wick series to start. You’ll choose the size in a bit.

If you’re combining several waxes into one, consider starting with the wick series for the wax making up the largest percentage of your blend.

You’ll know soon if your choice was insane or not.

Step 3: Measure diameter

Whether you’re using a mold or a container, find the diameter in inches.

Diameter, for those of you who may not remember (don’t feel bad), is the distance from one end of the circle to the other, straight across:

the diameter of a circle is the length across the middle

Now you’ve arrived at the intersection of art and science in candle making.

One wick, or multiple wicks?

Larger diameter containers, which are unofficially anything larger than 3-inches, typically benefit from multiple wicks in the candle. Regardless of your choice, the diameter plays a key role in your starting wick size(s).

If you’re using a square candle shape, us an approximation of the area. Here’s one suggestion:

use the estimated diameter of a square container

It’s not a perfect system since we don’t have wicks that burn in a square pattern (yet). Don’t stress over this too much – the nuances with square containers works itself out during the burn test.

Step 4: Choose three wick sizes

If it wasn’t clear before, this process involves a lot of “trying things out” to see if they work.

Most candle makers start with making three candles at once, each with a different size wick to see what happens.

Now, you don’t have to choose three wick sizes, but if you’re trying out something new or you haven’t done this before, building three candles at once helps narrow down the wick selection.

It can be a lot of work, but building a safe candle that performs well requires a fair amount of effort.

Sometimes you get lucky, but don’t settle for an unsafe candle just because you’re frustrated by the process.

Suggestions for troubleshooting annoyances are located at the end of this if you get stuck.

Single Wicking

  1. Navigate to a wick chart of your choosing. The CandleScience chart is a good start for most.
  2. Find the wick size that matches your series, wax, and diameter. This is wick size #1.
  3. Also select both the wick size up and down from the wick you chose above. These are wick sizes #2 and #3.

Multi Wicking

This approach is far simplified, but offers a decent starting point with multiple wicks:

  1. Divide your diameter by the number of wicks you intend to use. For example, if you want to wick a 3″ candle with 2 wicks, the answer would be 1.5″ (3″ ÷ 2).
  2. Use this number (1.5″ in the example above) as your effective diameter.
  3. Navigate to a wick chart of your choosing. The CandleScience chart is a good start for most.
  4. Find the wick size that matches your series, wax, and effective diameter. This is wick size #1.
  5. Also select both the wick size up and down from the wick you chose above. These are wick sizes #2 and #3.

Multiple wick designs are nuanced, and deserve an entire section – so consider this a rough starting point.

Step 5: Design your candle

This step is by far the easiest part of the process. Once you choose your wick (or wicks), finish laying out your candle design on paper.

Assuming you pour everything from a single batch, the remaining factors are:

  • Fragrance oil blend
  • Fragrance load
  • Color, if applicable
  • Container or molds (these should all be the same!)

Then just create your three candles, allow them to cure for a proper amount of time, and continue to the burn test.

Step 6: Burn test

The only way to know if your choice in wick worked is through a proper test.

Perhaps the most important part of testing is thoroughness. Many candle makers burn the candle a few times, think it’s fine, then turn around and sell it!

The best candle makers choose a wick, burn test, then react (described later on) to make sure the wick is safe and performs well in the candle.

This means testing the candle from start to finish – no exceptions.

We cover burn test tips in pretty significant detail here. There are many ways to burn test a candle, including but not limited to:

Industry Standard Burn Test

This test follows the procedure outlined in ASTM F-2417, which is commonly accepted in the United States as the industry standard for candle making.

It’s not the law but if you’re selling candles and not testing this way you should think twice.

In a standard test, the candle burns for four hours at a time until the end of it’s life or if it fails by exceeding one of five criteria:

  • Candle tips on its own
  • Surface the candle sits on is damaged
  • Flame height exceeds 3″
  • Vessel cracks or shatters (usually due to high heat)
  • Candle has more than one flame per wick

If four hours pass and nothing fails, extinguish and allow to cool back to room temperature before starting another 4-hour test.

Chaos Test

This test throws all standards out the window and burns the candle for extended amounts of time.

Also called a stress test, the candle is burned to prove that left unattended, or burned for a long time, is not detrimental to the user.

Normal Burn Test

Far less dramatic than the chaos test or standard test, the Normal burn test is exactly what it sounds like… normal.

Most people burning a candle tackle this endeavor without any structure or rules.

Trim the wick? Maybe – if you feel like it.

Blow it out after four hours? Only if you feel like it (or it makes it that far).

The purpose of a normal burn test is just to simulate a somewhat random approach to the candle.

Most people won’t burn their candles in any formal manner, so testing it informally (as you would burn a normal candle for recreation) is one further strategy to see how it behaves.

Step 7: Adjust if needed

Your wick is the right size if you can say “Yes” to the following questions:

  • Did you test the candle from start to finish?
  • Is the candle safe – does it pass all criteria in your test?
  • Was most of the wax consumed by the candle through its life?
  • Did the candle have an acceptable hot throw?
  • Was the candle free of any tunneling, sooting, or excessive heat?

If you couldn’t say yes to all those questions for any of the wicks you tested, choose a new wick (or several wicks) and make more candles (or use some of these hacks).

Wick Corrections Guide

You can use the following guide for recommended actions to take if your candle gives off a “signal”.

Signal Correction
Mushrooming Incomplete combustion leaves carbon on the tip – first adjustment is usually to lower the fragrance load if no other signals appear. Otherwise, wick is too large.

Lower FO or decrease wick size
Tunneling Wick is too small – not enough fuel to create enough heat to melt enough wax

Increase wick size
Sooting Unburned particles – sometimes means too hot. Could also mean too large. Typically not associated with too small of a wick.

Decrease wick size or change wick type
Tall Flame (>3″) Wick is too large and is generating too much heat.

Decrease wick size
Damaged surface or cracked container Wick is too large and generating too much heat.

Decrease wick size
Not tunneling, but leaving wax on the sides in excess Wick is too cool to melt all wax.

Increase wick size
Fuel smell Wick is burning too hot for the fragrance and is evaporating top and middle notes, possible some base notes too.

Decrease wick size
Self Extinguishing Wick is probably too small or it was trimmed way too short and doesn’t have time to draw fuel up.

Increase wick size

If your original three wick sizes all fail, check the chart above for corrections.

Sometimes failure might indicate there’s no real size in that series that could work (for instance, the wick size up and down from what you tried both lead you to believe you should choose a wick you’ve already used), consider changing wick series completely.

If nothing you’re doing seems to work – you’ve tried every series and size – make a bare naked candle (no fragrance oil or dye) and see if the same thing happens.

Most of the time, the key suspect is the fragrance oil, which is known to impact the burn tremendously.

Once you choose a wick that satisfies all criteria, you’re done! Enjoy the fruit of your labor.