Lather & Lye

Cold Process

Real soap made from scratch, explained patiently: how oils and a lye solution react (saponification), how to mix safely and reach trace, pouring, insulating, unmolding, cutting, and the multi-week cure that turns a soft loaf into a hard, gentle, long-lasting bar. A careful, confidence-building walkthrough for first-timers.

Cold Process

8 guides
Cold Process

Hot Process vs. Cold Process Soap: What's the Difference?

Hot process and cold process soap both use lye. Here's how the two methods differ, which one suits beginners, and what to expect from each batch.

July 1, 2026
Cold Process

How to Unmold and Cut Cold Process Soap

Learn when to unmold cold process soap, how to get bars out cleanly, and how to cut them evenly. Includes timing cues, tool tips, and safety notes.

June 28, 2026
Cold Process

How to Make Cold Process Soap: A Beginner's Step-by-Step Guide

Learn how to make cold process soap from scratch with this beginner-friendly guide covering lye safety, equipment, a simple recipe, and curing basics.

June 27, 2026
Cold Process

Gel Phase in Cold Process Soap: What It Is and How to Control It

Learn what gel phase is in cold process soap, how it affects your finished bar, and how to force or prevent it depending on your goals.

June 23, 2026
Cold Process

How to Mix Lye Solution Safely

Learn how to mix lye for soap the safe way: gear up, add lye to water, manage the heat, and understand lye-to-water ratios for cold process soap.

June 19, 2026
Cold Process

Curing Cold Process Soap: Why and How Long

Learn how to cure cold process soap properly: why 4–6 weeks matters, what happens during curing, and how to set up your rack for the best bars.

June 14, 2026
Cold Process

How to Use a Lye Calculator for Soap

Learn how to use a lye calculator for soap making step by step. Get accurate NaOH amounts, set superfat, and avoid caustic bars every time.

June 10, 2026
Cold Process

What Is Trace in Soap Making (and How to Reach It)?

Trace is the moment your soap batter emulsifies and thickens enough to leave a mark on its surface. Learn the stages and how to reach each one safely.

June 5, 2026

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