Seam lines occur when two mold parts don’t close perfectly or when excess filling creates pressure. Trim the joint with a warm knife and glaze or spray-coat the surface for a flawless finish. Proper filling technique helps prevent seam lines altogether.
3D molds can show a “joint line” where the mold parts meet. Causes include:
Overfilling, forcing the mixture out
Misalignment of the two parts
Uneven freezing, causing expansion
Fixing the seam:
Once frozen, trim gently with a hot knife.
Apply velvet spray, mirror glaze, or neutral glaze to hide micro-defects.
For chocolate, ensure correct tempering for clean contraction.
To prevent seam lines in the future:
Do not fill to the brim (leave 2–3 mm).
Check mold alignment before freezing.
Use clamps or elastic bands for rigid 3D molds.
