How to Make Lye for
Soap Making from Wood Ash
you how to make lye which is perfect
natural soap including some old, pioneer soap recipes. It isn't
difficult, although if you have access to
commercial lye, you may prefer to use that instead. This is because
commercial lye will give you consistency in your lye soap
recipes. However, if you live in an area where it is difficult to
source, and you have the right wood available to you, then you can
follow these steps to making your own lye.
You can also make your own lye using slaked or unslaked lime. See
recipes for these below.
The problem with making
lye from wood ash, although it is a
simple process, the end result can be that your lye water is either too
strong, or too weak. Either way, it could spoil your batch of homemade
Having said that, none of
our ancestors had access to
commercial lye and they made soap just fine. We will also give you a
couple of tests to do that will take a lot of the guess work out of the
process, making sure that your lye is of the right strength.
What is Lye?
Lye is a strong alkali that is used in soap making, among other things.
It is also known as caustic soda or sodium hydroxide.
The ingredients for making lye are wood ash and water.
Preferably rain water, as it is soft, although tap water will work just
as well. The ash should come from hardwoods as soft woods are too
resinous to mix with fat.
Wood for Making Lye
Only certain woods are
good for homemade lye. You will need to any hardwoods, not softwoods
such as Fir or Pine. The following common hardwoods can be used, along
with all other hardwoods, Hickory, Sugar Maple, Ash, Beech and
wood give some of the better results.
- Australian Red Cedar
- Sugar Maple
Traditional Method of Making Lye using a Wooden Barrel
Take an old wine barrel
and make sure that it is clean. Steaming it will give good results.
Elevate it so that you can then place a bucket or similar
underneath the leaching hole at the bottom of your barrel to collect
the lye water when it is ready to emerge.
Place a bung in any existing opening in the wine barrel, and drill a
smaller hole into the barrel that is only 1/8th inch wide.
What you are aiming for is a hole wide enough for the water to drip
through but small enough for the ashes not to fall out. Keep
this hole closed up with a small bung until later.
Now pack the bottom of the barrel with clean river stones. Make sure
that you get a good mix of both large and small stones as this will
work as a filtration system. If you don't have stones, you can also use
a thick layer of charcoal instead.
After a good layer of stones you will need to place a generous layer of
straw on the top of the stones. Your straw should take up at
least half way up the barrel.
Shovel in your ashes until the barrel is as full as you want it. After
that, pour over some hot rain water in small amounts so that the whole
contents are wet and soaking but not flooding. Using hot
important as the hot water will draw out more potash from the wood ash
than cold water, making your lye stronger.
a little lime was mixed with the ashes to 2 - 5% which then guaranteed
that you would have good lye for soap making.
On day 2 you can add
more ash and water after allowing the ash from the previous day to
- If your ashes start floating to the top then you know
that you have added too much water.
- Also, adding hot water to your ashes makes your lye
stronger than adding just cold water.
- To make your lye potash more like caustic soda you
can sprinkle a little quick lime onto your ashes before pouring on the
hot water. (Not easy to get in small quantites these days, and treat
with caution as it needs to be handled with extreme caution.)
On day 3, make sure your receptical is ready under the opening on the
barrel, remove the bung and wait for the lye water to slowly trickle
Don't expect to have a
bucketful. You will only be getting a small amount as this should give
you the right strength needed to make good natural soap.
At this stage you need to get it to an even strength to use for your
soap making. Boil this liquid again until you are able to do the "float
test" and get it to work. See instructions below.
Traditional Equipment used in
Picture courtesy of Carla
Emery from the Encyclopedia of Country Living
How to Test the Strength of your Lye
To make lye and be
successful at soap making your lye has to
be at the right strength. Now there are 2 ways in which this can be
done, both of which indirectly involve chickens. If you live on a farm
and keep chickens, then this test is fine for you. If not, then you can
use the second test.
This is a simple test.
Take a chicken feather and place it in
the lye. If the feather dissolves, the lye is strong enough and you can
use it for your soap. If not, you will have to re-boil the lye water
when it emerges and repeat the process until your chicken feathers
This test involves using a
fresh, whole egg or a potato works just as well. Take the egg or potato
of similar size and place it in the cold lye water. If it sinks,
your lye is not strong enough and you will have to repeat the process
until it does.
If the potato floats with
just a little of the lye water
above it; about an inch showing above the water, or the head of the egg
sinks to just half-way down, then the strength is just right. If the
potato or egg floats too high,
almost on top of the lye water, then the strength is too strong. You
can compensate by adding a little bit of fresh water to the lye water
and try again.
With the first test, I
would still back this up with the "egg
floating" test, just to make sure that my lye water was not too strong.
Modern Method of Making Lye using A Plastic Bucket
Traditionally, as you have just read, people used
wooden buckets or casks lined with straw and small rocks to make lye.
everyone has access to these things, so I am going to show you how you
can make lye just as easily in an old nappy bucket or something similar.
Take your old plastic nappy bucket and drill a neat round hole, about
an inch off the bottom on one side of the bucket. It shouldn't be very
big, about the diameter of a small iron nail - about 1/8th of an inch.
Make sure that the size of the hole is the same size of the nail that
you will use to stop up the hole when needed.
Using cold wood ash,
take a spade and carefully place the ash into the stopped-up bucket.
Make sure that what you are placing in the bucket is the fine, white
ash, as opposed to any charcoal bits. This you don't need. Make sure
that the ash is well compacted in the bucket.
Boil water half of the
capacity of the bucket and pour gently over the ashes. As soon as the
water makes contact with the ash it will start hissing and bubbling.
This is perfectly normal.
You may find at this stage
that the water is
just sitting on top of the ash, without it appearing to do anything.
Just leave it, without disturbing it, and come back later to see when
you can add the rest of the water.
Once you have used all the
water elevate the bucket so that you are able to place a glass or
plastic container under the hole that you previously drilled and
stopped up with a nail. Place your receiving container under the hole
and remove the nail. Do not expect lye water to come out of here. This
could take hours, if not days.
Once you have enough lye
water use the nail to stop up the hole. Take the lye water to the
kitchen and boil carefully.
Take care at this stage as
the lye is
caustic and if it splashes onto your skin and into your eyes it will
burn. You will need ot wear gloves and safety glasses at this
Once you have heated up
your lye water take it back to your bucket and
carefully pour it back over the ashes in the bucket. This helps
strengthen the lye.
Wait for the lye to emerge
Drying Lye to Form Crystals
When you buy commercial lye it is in
the form of crystals. When you make lye at home you will want your lye
to be in crystals too. This is very easy to do. Take your lye water and
place it in the sun until the water has evaporated. What you are left
with are your lye crystals that you can use quite happily in your soap
How to Make Lye using Unslaked Lime (Calcium Oxide)
Unslaked lime is a chemical compound known as calcium oxide and also
known as lime or quicklime.
Put a half pound of unslaked lime into 2 gallons of water. Add 6 pounds
of washing soda and boil gently for 1 hour or so. When cold, pour off
the liquid part which is your lye.
Take 10 quarts water, 6 pounds quicklime, (shell lime if possible),
and 6 pounds of washing soda. Boil for 1 hour or so. When cold, pour
off the liquid which again is your lye.
How to make Lye using Quick Lime (Calcium Hydroxide)
Calcium hydrixide is a chemical compound known more commonly as slaked
lime. It is formed when calcium oxide is mixed with water.
Put 3 pounds of washing soda, 3 pounds of slaked lime, and 12 quarts of
water into a large pot. Boil for 20 minutes. Wait for the contents to
cook, and when cold, pour off the liquid part which is your lye.
How to Use Homemade Lye in Soap Recipes
In the end your homemade lye is softer
on the skin. It is potassium hydroxide as opposed to sodium hydroxide.
When following soap recipes make sure that you use the right type of
hydroxide, as although both are lye, they cannot usually be used in
place of the other in certain recipes.
The potassium hydroxide molecules are
larger than the sodium hydroxide molecules. It is this size difference
that enables the potassium hydroxide to maintain a liquid
Potassium hydroxide is normally used to
make liquid soaps.
And when our ancestors made soap using homemade lye, most of
the time they ended up with liquid soap because the lye they were using
wasn't strong enough.
However, you can make a hard
soap by adding common salt at the end of the boiling
process. If you want to add salt to harden your bars of soap, weigh out
the water you are going to mix your lye with.
Before you add the lye, add ½ tsp. of
salt per pound of oil/rendered fat in your recipe. Stir well to make
sure that all of the salt is dissolved. Add your lye to the salted
water, making your lye solution, and resume your normal soap making
procedure. Both types of hydroxide, however, are extremely corrosive
and must be handled and stored with care.
The traditional ratio is 2 pounds fat
or grease (such as bacon fat) to 1 gallon homemade lye.
Natural Soap Recipe using Homemade Lye
Here is an original pioneer soap recipe using your homemade
2 pounds fat
1 gallon homemade lye water
2 tablespoons white vinegar
1/2 cup hot water
Place the fat and lye
water in a large
pot suitable for soap making (not aluminum) Add the vinegar mixed in
with the water.
Keep on a
until thick and slimy. This can take several hours.
If at this stage you
want to use it was soft soap it is ready after
straining through several layers of cheesecloth before placing in
storage containers. 1 cup of homemade liquid soap per load is all that
If you want hard soap
you will need to add 1 teapoon salt dissolved in
a little water to the mixture at this stage and boil for
longer. Skim the foam off the top and place the liquid into molds and
allow to set.
Another Pioneer Soap Recipe using Homemade Lye
Fill a pot
2/3rds full of homemade lye. Place on the stove over a medium heat and
ladle in ladlefuls of melted lard and stir until your mixture
creamy. Now add handfuls of salt to the mixture and stir until a ring
of soapy mixture is left behind and very evident on the stiring spoon.
from the heat and allow the soap to harden. After it has hardened you
will need to drain the remaining lye water off the soap.
You can make soft soap in the same manner if you don't add the salt at
the end of the process.
Making Soap page for more information on
how to make soap at home. You will also find
Soap Recipes for the three main types of
soaps; hand-milled soaps where you do not have to use raw lye, cold
process and hot process soaps.
Other Resources on Soap etc. that you May be Interested
from Lye from Wood Ash to Soap Recipes
to Homemade Laundry Soap Detergent
to the Saponification Chart
Go to Traditional
Buying Lye off the Internet
If you can't be bothered to make lye the old-fashioned way then perhaps
you may be interested in purchasing these products through our partner
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