The Wick
How a cotton braid decides everything downstream.
Wick selection is where most new makers spend money they did not need to spend. They buy one wick size, it fails, they buy the next size up, it fails differently, and they blame the wax. The matrix on this page is the shortcut I wish I had been given in year one.
Read the matrix, then ignore it
The decision matrix crosses vessel diameter against wax family and drops a starter wick size into each cell. Start there. Do not stop there. The matrix cannot know your fragrance load, your vessel wall thickness, or your room temperature. It gets you within one size, which is close enough to begin testing.
For a 75 mm soy vessel the matrix suggests a CD-12. Buy the CD-10, CD-12 and CD-14. Three sizes, three identical candles, one weekend of testing. That is the three-wick test and it is not optional. Anyone who tells you they picked a wick right first time is either lucky or lying.
Wick anatomy matters
A wick is not a piece of string. It is a braided structure engineered to bend a specific direction as it burns, which pulls the ash away from the flame. That is why CD wicks curl one way and HTP wicks curl the other. Do not mix families mid-range because the burn character will shift and your protocol notes stop being comparable.
The trim ritual
Trim to 5 mm at a slight angle before every burn, including the first. The angle matters. A flat cut mushrooms because the ash has nowhere to fall. A 45-degree cut sheds ash cleanly into the melt pool where it burns off. The trim guide on this spread is annoying to read the first time and second nature after ten pours.
Trim while the wax is still warm from the previous burn. Cold wicks are brittle. They shatter under wick trimmers and leave a jagged base that mushrooms on the next light.
- Three consecutive wick sizes ordered (matrix ±1)
- Three identical vessels, same wax lot, same fragrance load
- Trim tool and 45° reference guide on the bench
- Burn log printed and dated per candle
- Camera position marked with tape for repeatable photos
- CD (cotton, paper core)
- Self-trimming curl. Good for soy and coconut blends. Curls toward flame; ash falls into pool.
- ECO (flat-braid, paper thread)
- Rigid stand, minimal mushroom. Soy and parasoy containers, 50 mm to 90 mm diameter.
- LX (flat-braid)
- Vegetable and paraffin blends. Consistent flame; sensitive to fragrance load above 8%.
- HTP (paper-cored, twisted)
- Curls opposite to CD. Runs hot; suits dense soy and pillar blends. Watch for mushrooming above 4-hour burns.
- CDN (cotton, no core)
- For high-fragrance-load soy. Neutral curl, minimal soot when trimmed at 45 degrees.
- RRD (rigid, ribbon)
- Large-diameter vessels (90 mm+). Requires vessel wall thickness above 3 mm to stay safe.
- Wooden (single or booster)
- Wide flame, audible crackle. Requires flat pour surface and a fragrance load between 6% and 9% to stay lit.
| Symptom | Likely cause | Fix | Prevent |
|---|---|---|---|
| Mushroom head larger than 3 mm after four hours | Under-wicked, or fragrance load above the wax's rated ceiling | Step up one wick size and hold fragrance load constant for the next test | 45° trim to 5 mm before every burn; log mushroom size at hours 1, 2, 4 |
| Sooting on the rim within the first burn | Flame height above 35 mm or fragrance oils above the wax's rated load | Drop one wick size first; only then drop fragrance load by one percentage point | Photograph flame height at 30 minutes; compare against the ASTM ceiling |
| Flame drowns in its own pool by hour two | Over-wicked, or wick trimmed below 5 mm | Step down one wick size; re-trim to a clean 5 mm before relighting | Keep the trim reference guide on the bench; do not eyeball the length |
| Flame dances or forks constantly | Wick off-centre by more than 2 mm, or draft from a nearby vent | Re-centre with a wick bar during the next pour; move the burn test away from vents | Use a centring bar, not chopsticks; mark the pour position on the bench |
| Hard carbon ball forms at the wick tip | Wick family mixed mid-range (e.g. CD to HTP) so the curl no longer sheds ash | Return to a single wick family and re-run the four-burn protocol from candle one | Order all three test sizes from the same series; never substitute mid-range |
The wick is the failure surface. Everything else is decoration.
Waxverse Studio