Structural
Candle surface cracks after cure
Cracking is a temperature problem. The wax shrinks faster than the surface can flex. Common in paraffin pillars and in soy candles cooled too quickly.
Written by Maya Holloway
Likely causes
- Cooled too fast (cold draft, cold surface).
- Cooled too slowly without surface support (paraffin).
- Excessive additive load (stearic, Vybar).
How to diagnose
- Note ambient temperature during cure.
- Inspect cracks for depth: hairline (cosmetic) vs deep (structural).
What to change next batch
- 01
Cure on a flat warm surface; avoid placing candles directly on cold stone or metal.
- 02
Heat-gun the top to seal hairline cracks.
- 03
For pillars, top-off pour to fill deep cracks.
Related symptoms
- Sinkholes form around the wick after pour
Caverns under the surface as the wax contracts.
- Rough or grainy tops after cure
Surface looks pitted, not glassy.