lemonade learning The Science 
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An Important Note About Lye and Safety

Lye, also known as sodium hydroxide or caustic soda, can be quite dangerous to work with. If it is not handled properly, it can create a volcanic effect and burn skin severely.

  • When handling lye, always follow the safety precautions on the container.
  • Wear gloves, long sleeves and eye protection when handling.
  • Always do your initial mixing outdoors or in a well-ventilated area.
  • Keep a bottle of vinegar handy to quickly help neutralize any spills.
  • The addition of the lye should be done by an adult.
  • Children who help should be insructed on basic safe handling procedures.
  • Move slowly and deliberately when handling the lye.
  • Always add the lye to the water, not the water to the lye in order to avoid a sudden volcanic reaction.
  • Do not use aluminum containers or utensils as the reaction can create hydrogen and explode
  • Keep the lye away from painted surfaces as it may damage them
  • Avoid inhaling fumes, particularly as you combine ingredients.
  • Do not handle soap with bare hands for the first few days after it sets as it may still burn your skin.
  • Do not substitute drain cleaners for lye as they will not be pure and could cause burns, skin irritation etc.
  • Once the soap has cured for three weeks, it is perfectly safe to handle.

Soap making is accessible to children, but proper protection, instruction and supervision is an absolute must, particularly when handling lye. A responsible adult should be the one to combine the lye and water as this is the most dangerous step; pouring into moulds should also be done by an adult. The measuring, melting and stirring are ideal jobs for a child helper.

soap making


saponification: means "making into soap"; it is the reaction that happens when lye (sodium hydroxide, and also known as caustic soda) mixes with oils or fats.

trace: this is the point at which the mixture will not settle out when left to sit; it can be tested by dribbling a little on the surface: when it stays there for a few seconds before sinking, the mixture has reached "trace".

lye: this is the common name given to sodium hydroxide, and is also known as caustic soda. Be sure to use only pure varieties (you can get this at Home Hardware, particularly in farming communities)

essential oils: these can be purchased at health food stores

Unusual oils such as sweet almond, jojoba oil, etc. can also be found at health food stores and anywhere that sells natural cosmetics.

soap making

Oatmeal Soap

5 oz. water
2.11 oz. lye crystals
6 oz. olive oil (don't bother with fancier types as those features are lost in soapmaking)
5 oz. sunflower oil
4 oz. coconut oil
1 oz. beeswax
2 tablespoons steel cut oats: a quick pulse in a blender with make these smoother; use them as is for maximum abrasion
optional essential oil: lavender, pine or lemongrass

large pyrex measuring cup or heatproof large glass jar
digital kitchen scale
kitchen thermometers (ideally 2, but if you keep an old cloth around for wiping, you can get away with 1 in a pinch)
stainless steel or pyrex pot, or a second large (4 cup) pyrex measuring cup
mould(s): you can use silicone bakeware, the bottom of a milk or juice carton, or line a wooden box with parchment paper
rubber gloves for each person
safety goggles for each person
a stainless or wooden spoon for mixing
optional: a stick blender

This is a gentle soap suitable for both face and body.

  1. Measure out your oils into a saucepan (including the beeswax)
  2. Measure the water into the measuring cup or jar
  3. Heat the oil to melt the beeswax and coconut oil and stir together (it will naturally layer as it sits)--you can do this with short bursts in the mircrowave or on the stovetop. Heat the oil until it is all melted, then bring it to a target temperature of 100 degrees F.
  4. While the oil is heating, don your protective clothing and add the lye to the water. Before adding the lye, let the kids (who have their own gloves on now) feel the outside of the container. Once the lye has been added, wait a moment then let them feel the container again. It will be remarkably hot, since the combination of sodium hydroxide and water creates a quick exothermic reaction, which will bring the solution close to the boiling point. This is another reason why the gloves are important!
  5. Measure the temperature of the oil and of the lye/water. Once both have reached 100 degrees Farenheit, pour the oil into the lye solution and stir.
  6. The soap will appear cloudy. Stir in a figure-8 pattern or with a stick blender until it begins to trace. Depending on the ambient temperature, humidity, etc. this can take from about 10 minutes to an hour. You will know it has traced when you can drip some on the top and it does not immediately sink.
  7. Now you may stir in 6-12 drops of essential oil and the oats.
  8. Pour into moulds and cover with a layer of waxed or parchment paper and let sit for a couple of days to harden.
  9. Remove from moulds and cut as needed. Let sit for 3 weeks from the start of the process before using to allow the lye to finish neutralizing.
  10. Enjoy!

Note: You may adjust the oil amounts to meet your own needs; use the lye calculator link in the menu above to determine how much water and lye to use with your own personal oil ratios.

Do It Yourself Soap Recipes

You can make your own soap recipes by using the lye calculator link at the top of the page.
Some guidelines you should follow for optimal success:

Bar Shampoo

The convenience of bar shampoo hit home years ago when I took a bar I'd purchased from Lush in traveling with me. No worry of spills, and many washes from a single bar make it not only a luxury, but also very practical.

4 oz. castor oil
2 oz. coconut oil
2 oz. jojoba oil
2 oz. olive oil
1 oz beeswax
3.5 oz. water or chamomile tea
1.24 oz. lye crystals
essential oils of your choice, ~8 drops (yling ylang, patchouli and/or peppermint are especially nice)

see "Oatmeal Soap Recipe" above

Method: Follow the method for "Oatmeal Soap Recipe" above. When considering moulds, aim to make the bars somewhat smaller than regular bar soap.
To use: lather a little in your hand or rub the bar directly on your head. Lather, rinse, and repeat as desired. The castor oil improves the lathering and the jojoba and coconut oils help moisturize your hair. Using chamomile tea in place of water will help bring our blond and reddish highlights.