sodium hydroxide

Overview
The chemical sodium hydroxide (NaOH), commonly called soda lye, is an essential ingredient in soapmaking. Sodium hydroxide was previously available on grocery shelves as Red Devil lye, but this product has been discontinued.

Production

 * How to Make Lye
 * Making lye from wood ash: this link claims that lye made from wood is potassium hydroxide, but this contradicts the WikiHow page above and Harena's understanding

Purchasing
see also lye: places carrying more than one type of lye are listed here
 * Where to Buy Lye (David Fisher, about.com)
 * Texas Natural Supply