Tuesday, May 14, 2013

Making Soap From Wood-Ash Lye


The key to staying clean is using soap. Soap helps break the chemical bonds of dirt and stains to fabric and other items. It also helps to kills germs, including dangerous bacteria, which serves to keep us healthier. However, when you’re living amongst the trees, miles from any town or store, soap is difficult to come by. And even if you live down the street from a store and have access to soap, you may wish to make your own, for the experience and to save a little money.

A story I read says that the ancients noticed that when washing their clothes in the river, the clothes usually got cleaner after a rain. So, initially it was thought that rain water helped clean the clothes. However, later it was realized that this cleaner process only occurred in the river downhill from the area where animals were sacrificed as burned offerings. Now, whether this story is factual or not, it describes the three very basic ingredients of soap: 1) Water (rain water is preferred); 2) Fat (any animal or plant fat); and 3) Lye (homemade or commercial).

Wood Ash Lye vs. Commercial Lye

There is a difference between homemade, or original lye, and commercial lye. Homemade lye is Potassium Hydroxide and can be made rather simply at home from wood ashes Potassium Hydroxide makes a softer soap, so the fat or oils used will need to be beef tallow (beef fat) or even lard (pig fat). You can use other fats, but the finished product will be much softer.

Commercial lye is Sodium Hydroxide, which is much more complex to manufacture, and is often used in drain openers. In order for commercial lye to work properly in soap, it must be pure sodium hydroxide, which is becoming difficult to find in grocery stores. If you are not sure if your lye is pure, you can look at the crystals. If you see flecks of gray or black, you should avoid it when making soap. You can also ask the manufacturer.

Safety Precautions

Both types of lye are very caustic and can cause serious burns and injuries when they come in contact with skin and eyes. In my experience, commercial lye is extremely caustic and unforgiving. Take it seriously and wear eye protection, protective gloves, and keep all skin surfaces covered when working with any type of lye.


When the right amounts of lye, water, and fat are mixed together, a process called saponification takes place. Saponification is where the chemical compounds of these ingredients change places to form a different product, which we call soap.

Cold Process or Cooked Process?

There are two types of soap making processes: 1) the cold process, and 2) the cooked process. With the cold process, the right amounts of ingredients are put together, mixed for long periods of time, depending on the fat/oil used, poured into a mold, and then dried. The cooking process works well for re-batching, usually because you want to either 1) fix a soap batch that didn’t work so well; or 2) recycle left over soap cakes and slivers by adding them to a new batch of soap.


There are also many possible additives to soap, such as colorings, herbs, flowers, honey, oatmeal, abrasives, essential oils or fragrant oils . An essential oil is the natural oil that is extracted from a plant for its fragrant or medicinal properties, whereas, a fragrant oil is a man-made chemical which smells like a plant. The mint essential oil actually comes from the mint plant, while the mint fragrant oil was made in a laboratory and smells like mint. Typically, the fragrant oils are less expensive, but obviously not natural. To date, I have not added any coloring, fragrant or essential oils to my soap recipes. Glycerin is sometimes added to soap, and milk is sometimes used in place of the water.


When making soap, I’ve always used homemade lye. There are many different recipes, and many combinations of ingredients. Various combinations of fats and oils will result in very different soaps. I have used straight olive oil, which produces a much softer soap when made with homemade lye. I’ve also mixed beef tallow , lard, and olive oil. Straight beef tallow renders a harder soap. Other popular oils for use in homemade soaps are palm oil and coconut oil.

Toss It In, or Measure First?

Now, here’s where your personality will actually affect your end product. I use one of two basic techniques when I make soap. One method requires that each ingredient be meticulously measured. With the other “technique” you just add a little of this and a little of that until it looks the way you want it to look. I must say, not measuring takes a lot more time. I’ve found that I inevitably add too much fat, for example, and then I must compensate by adding more lye, and then maybe a little water.

Once you learn the properties of the different ingredients, you’ll develop your own style of making soap. With homemade lye, you can have the fun of unpredictable soaps, or you can work on more consistency with each batch.

Enough Soapbox. Let’s Make Soap!

Making Lye In The Fast Lane

Toward the end of this article, I’ll give specific recipes for making soap, both with commercial lye and with homemade lye. There are countless recipes for making soap, but this will serve as a guide.

For this batch of soap, I made a fast batch of homemade lye. Today, the lye-making took approximately 2-3 hours, instead of 3-5 days for a normal batch of homemade lye from wood ashes. If you’d like to try the regular method of making lye from wood ashes , see the June/July/August 2007 issue of Frontier Freedom Online Magazine .

First, I began with a 5 gallon bucket of rain water. It was raining that day, so I took advantage of the situation and collected it from the gutter downspout. While nature and gravity were working together to provide me with soft water, I grabbed an old pillow case and filled it with wood ashes. You could also melt snow instead of using rain water if you live in a colder climate.

Next, I placed the pillow case full of ashes in a separate 5 gallon bucket. I then boiled about a gallon of rainwater. With the pillow case stretched open to the same size as the bucket, I poured the boiling hot rain water into the ashes. I then boiled more rain water and repeated this process until the ashes were completely covered.

With the hot water covering the ashes, I closed the pillow case and lifted and lowered the pillowcase in and out of the water, like making tea.

This dipping process continues for some time --- about one and a half hours. Then lift the pillow case out of the bucket, strain it, and pour the water into your pan. I used my enameled pot. Using my propane grill, I cooked the contents of the pan, which contained water and lye (Potassium Hydroxide). The reason for cooking this mixture instead of going straight to combining it with my fat was to boil the water away so that I could use the lye faster. In the regular method , you would allow the water to evaporate out of the lye until the potassium hydroxide was dry. Then you could easily store it for making soap anytime. But, today, we’ll make the lye quickly, then use it in a batch of soap.

Occasionally, I checked the strength of the mixture with a chicken feather. The rule is, the lye is strong enough to make soap when a chicken feather begins to dissolve in the solution. Today, my feather began to dissolve in the solution, so it was ready.

If the feather had not dissolved, I would have taken the following steps:

  1. Put the pillowcase of ashes back into the 5 gallon bucket
  2. Poured the contents of the pot back into the pillow case.
  3. Continued dipping the pillow case repeatedly, and then retest the mixture until I obtained the results I wanted --- a feather beginning to dissolve.

However, since I was happy with the results, I continued to boil the mixture down to almost nothing. Be careful when the level of liquid gets low, as you can scorch the lye.

Mixing Fat With Lye

After the lye has passed the “Feather Test” and the water has boiled off, we’re ready to go. Now, if you’ve already made lye using the regular method, you can skip the “Fast Lane Lye” section, and start right here.

When the lye was ready, I added some beef tallow, which I melted in another pan. I also added an olive oil soap mixture that I had been working on, but that was simply too soft for me right now. Using my wooden stirring stick, I stirred the fat and lye water mixture until thickened.

(Editor’s note: By the way, a soft batch of soap is not lost. There are several ways to use it, depending on how it turns out. You could scoop it into a dish or short, wide mouth jar. If it’s pourable, you could pour it into a squirt bottle or a liquid soap pump dispenser. Soft soap can also be used to wash dishes or your laundry.)

After some time of stirring it looks thick, as shown in the picture --- about the consistency of sour cream, or maybe melted chocolate. Then I let the soap rest in the pan to begin setting up while I prepared the empty soap mold.

Soap Molds

The mold I used here is homemade. The interior of the mold measures 11”L x 2 ¾” W x 2 3/8”H. It was made from some scrap boards I had around, and a piece of paneling for the bottom. You’ll want to have a mold handy before you begin making soap. If you don’t have a wood mold available, you can use a shoe box, other type of box, baking pan, plastic food storage containers, or just about anything else you can think of. Just be sure to line it with plastic wrap before pouring in the soap. There are all sorts of things you could use for individual soap molds, as well, such as candy molds or those plastic dividers that are often used in tins of cookies.

To prepare the mold, I line it with plastic wrap to make it easy to remove the soap later.

Once the mold is prepared, I pour in the molten soap, spreading it around so that it’s even with the top of the mold. Even though this soap looks like refried beans, it dried to a nice, semi-soft white-gr
ay soap. For harder soap, I would omit the olive oil. But, I’m getting ahead of myself. As soon as the soap is poured into the mold, it should be covered with something to allow it to cool and harden slowly ---- cardboard, Styrofoam, towels or blankets will work.

Cutting and Curing the Bars

After the soap has dried in the mold at least 24 hours (in this case, it was more like 72 hours, but some soaps go much longer), it should be removed, cut, and stacked for drying. If you use plastic wrap to line your molds, the soap should come out easily. Then you can unwrap the soap after you remove it from the mold.

If you use one large mold, like I do, you’ll need to cut it into bars. The easiest way to cut soap is with a wire or piece of fishing line, as shown in the pictures. Do this before the soap becomes too hard. If it’s too hard, it will crumble or break when you try to cut it. If it’s too soft, you’ll have trouble cutting it without mashing it out of shape.
This block provided ten bars of soap. These bars will sit in my basement, stacked as shown, on a shelf covered with wax paper or plastic wrap while they cure and dry for the next 4-6 weeks. Uncured soap is called ‘green soap’ and can cause skin burns. Also, as the soap cures, the saponification (chemical reaction) is still taking place. You cannot hurt the soap by allowing it to cure too long.

The Standard Batch Soap Recipe

Below are two standard recipes. One calls for commercial lye, and the other is for homemade lye. Both will yield an excellent hard soap for bathing and laundering.

The following recipe yields roughly nine pounds of soap, enough to make about 36 bars. The soap can be molded separately or poured into one large container and cut into bars later. A combination of half tallow and half lard is usually suggested. Most other soaps are variations of this standard recipe.
Commercial Lye Crystals Homemade Lye
13 ounces of commercial lye crystals

1 1/2 pints of water
6 pounds of fat
18.2 ounces of homemade lye

2 1/2 pints of water
6 pounds of fat

  1. With either recipe slowly add the WATER to the LYE.
  2. Bring both the lye water solution and the tallow to about body temperature.
  3. Combine the two in a glass bowl and mix until the consistency is about that of sour cream. The lighter the oil, the longer the mixing will take. For soap that floats in water, add sodium bicarbonate (baking soda) to the mixture.
  4. Add color and scents, if desired.
  5. Pour the mixture in a mold(s) and place in a warm location.
  6. Cover the mold(s) with cardboard, Styrofoam, or blankets.
  7. After at least 24 hours, or when the soap is firm enough to handle, remove soap from mold(s).
  8. Leave uncovered in freely flowing air for at least 2 to 4 weeks to cure. Many soap makers allow their soap to cure 6 to 8 weeks. Remember, soap that has not cured long enough can cause skin burns. It won’t hurt the soap to let it cure longer.

The Single Bar Recipe

If you don’t want to try a large batch of soap just yet, then here is a recipe is for a single bar of soap. You could also use this as a guide if you want to experiment with a new recipe:
Commercial Lye Crystals Homemade Lye 
2 heaping tablespoons of commercial lye 
1/2 cup soft water

1 cup melted beef tallow (fat)
3 heaping tablespoons of homemade lye 
1/2 cup soft water

1 cup melted beef tallow (fat
Instructions for making a single bar are the same as for the larger recipe, above.

Enjoy your soap making! Once you get the basics, you’ll have fun experimenting.