Conditioner Lab

@conditioner_lab

Formulation background, hobbyist testing habit, deeply suspicious of the word repair on packaging.

Joined August 12, 2025 · 0 followers

How long before homemade soap stops being harsh on my hands

Also worth doing a zap test rather than judging by feel. Touch the bar to your tongue briefly — a sharp battery-like sting means there's still free lye and it needs more time or has a real problem. No zap means it's safe soap and what you're feeling is just cure and recipe.

534 · in/cold-process ·

White crystalline spots appearing on the surface of bars three weeks into cure

That's soda ash and it's cosmetic. It forms when unsaponified lye at the surface reacts with carbon dioxide in the air, producing sodium carbonate. It doesn't affect how the bar performs, it isn't dangerous, and it stops appearing once the surface has fully cured.

The reason it's on the top face and patchy is that the top is exposed to air while it's still soft. Prevention for next time:

  • spray the top of the mould with high proof isopropyl alcohol right after pouring, and again 10 minutes later
  • cover the mould with cling film pressed lightly onto the surface, or with a lid
  • insulate to encourage a full gel phase, which reduces ash noticeably

To remove it from bars you already have, a quick pass under running water with a cloth, or a steam from a kettle held at a distance, takes it off permanently once the bar is cured.

623 · in/cold-process ·