mixing the lye
- Accurately weigh the caustic soda.
- Add the caustic to the water.
Important - read the safety instructions for handling lye before mixing.
When measuring the ingredients into the jugs be sure to remember to tare or zero the scales.
1. Weigh the water into the first jug.
2. Weigh the caustic soda into the second jug and set aside.
3. Carefully pour the caustic soda into the water (not the water to the caustic soda) in a well ventilated area and stir gently until completely dissolved. Cover and set aside to cool (this may take several hours).
Measure
Accurately weigh the oils, place in the stainless steel pot (do not ever use aluminium as it will react with the lye) and heat slowly to 400C. Remove from heat.
- adding the lye
Mix Lye into Oil
Carefully pour the lye solution into the soapmaking oil in a steady stream and gently stir. The mixture will thicken and become opaque.
- Stick blender makes stirring easy!
Stirring
Keep stirring until you can drizzle some of the mixture from the spoon back onto the surface leaving a pattern. This is known as "tracing" and it looks a bit like a thick custard or pudding mix.
Recipes higher in saturated fat (coconut,palm etc.) will reach tracing more quickly than those containing unsaturated oils such as olive oil (see notes).
A hand held blender, or "stick" blender, can shorten tracing time considerably. For instructions, see notes.
Tracing
- Heavy trace
- add nutrient oil
Once tracing occurs keep mixing till the soap has reached the consistency of thick (but not stiff) custard, and then add any additives (nutrient oils, colouring, vegetable solids, etc.) and stir thoroughly to combine.
- add essential oil
Add Essential Oil
Lastly add any essential oils and only stir enough to just combine the essential oil with the soap mixture. Over stirring at this stage may cause seizing.
