Grate a 14.1 oz bar of zote or 5.5 oz bar of fels-naphtha like cheese, put in sauce pan with 4 cups warm water stir over medium heat until soap dissolves. Fill 5 gal bucket 1/2 full with hot tap water, add melted soap, 1 cup super washing soda, 1/2 cup borax. Stir til all powder is dissolved. Fill bucket to top with hot tap water while stirring. Cover and let sit overnight to thicken. Fill discarded containers 1/2 full of soap mix and top off with water. Shake before each use.
Top loaders use 5oz soap for 180 load yield, front load 2 oz for 640 load yield.