Soap making materials
Everything you need to make your first batch, and a fair amount you don't. Plenty of it is already in your kitchen - though a few things in there should never come near lye.
Essential you shouldn't start without it · Likely at home check the kitchen first
Safety gear
Non-negotiable. Buy this before you buy anything else.
- Chemical splash goggles
Sealed goggles, not safety glasses and not everyday spectacles. A lye splash to the eye can blind. Wear them from the moment the lye container opens until everything is washed down.
- Chemical-resistant gloves
Nitrile or dishwashing gloves. Latex is thin and tears. Keep a spare pair - you will occasionally need to peel one off mid-batch.
- Long sleeves and closed shoes
Raw batter is caustic until it saponifies. Cover your arms and don't work barefoot.
- Ventilation
An open window and an extractor fan, or mix the lye solution outdoors. The fumes in the first minute are genuinely unpleasant and shouldn't be breathed.
- Running water nearby
For flushing skin or eyes immediately. Know where the tap is before you start, not while you're squinting.
Weighing and measuring
Soap making is weighed, never measured by volume. This is where accuracy actually matters.
- Digital scale, 0.1 g resolution
A 5 kg capacity scale reading to 1 g works for oils; 0.1 g is better for lye and fragrance. A tare button is essential. This is the one piece of equipment worth spending on.
- Small jeweller's scale (0.01 g)
Optional but useful for colourants, additives, and small fragrance amounts where 1 g of error is a large percentage.
- Thermometer
Infrared or a probe thermometer. You'll be matching lye solution and oils, usually somewhere around 90-120°F / 32-49°C.
Containers and mixing
Material matters here more than anywhere else. Lye attacks some of what's in your kitchen.
- Heat-safe lye pitcher
Polypropylene (#5 plastic) or stainless steel with a handle. The solution reaches near boiling on its own, so thin plastic will warp.
- Large mixing bowl or stock pot
Stainless steel or heavy #5 plastic, big enough that the batter fills it halfway at most. Room to blend without splashing is worth the extra size.
- Stick blender (immersion blender)
Turns hours of stirring into minutes. A basic model is fine. Stainless shaft preferred; look for one whose bell doesn't trap air.
- Silicone spatula
Scrapes the bowl clean and handles heat and caustic batter without degrading. Buy two.
- Stainless steel whisk or spoon
For stirring the lye solution and for hand-mixing additives.
- Small containers for additives
Little glass or plastic pots for pre-weighing fragrance, clay, and colourant so you're not fumbling once the batter is moving.
What not to use
This list prevents more accidents than any tool on the page.
- Never aluminium
Lye reacts with aluminium, producing hydrogen gas and ruining both the pot and the batch. No aluminium pots, foil, utensils, or foil-lined moulds.
- Avoid glass for lye solution
Repeated exposure etches glass and it can fail without warning while full of caustic liquid. Use #5 plastic or stainless instead.
- Not wooden spoons for lye
Lye degrades wood - it roughens, splinters, and sheds fibres into your batch. A wooden spoon is fine for stirring oils only. Use stainless or silicone for anything caustic.
- No non-stick, tin, zinc, or copper
Non-stick coatings scratch and flake; the reactive metals corrode. Stainless steel, silicone, and #5 plastic are the safe set.
- Don't share with food
Keep a dedicated set of soaping equipment. Cross-use with cooking gear isn't worth the risk, and fragrance oils are stubborn about leaving.
Moulds and cutting
You can start with what's in the cupboard and upgrade later.
- Silicone loaf mould
The usual starting point. A 1 kg oil batch fits a standard 10-inch silicone loaf. Unmoulds cleanly with no lining.
- Lined cardboard box or loaf pan
A shoebox or bread tin lined with freezer or parchment paper works perfectly for a first batch. Don't use bare metal tins.
- Individual silicone cavity moulds
Handy for testing small batches or making guest bars, though bars cure more slowly with less airflow around them.
- Knife or soap cutter
A large non-serrated kitchen knife cuts fine. Dedicated cutters and mitre boxes give straight, consistent bars if you're selling.
- Insulating towel or blanket
Wrap the mould to encourage gel phase; leave it uncovered or refrigerate to prevent gel.
Ingredients to start with
A small, cheap shopping list makes a genuinely good bar.
- Sodium hydroxide (NaOH)
For bar soap. Buy soap-making or food-grade purity, at least 98%. Drain cleaners often contain additives and shouldn't be used. Potassium hydroxide (KOH) is for liquid soap.
- Distilled water
Tap water's minerals can cause dull bars, orange spots, and inconsistent results. Distilled costs almost nothing and removes a variable.
- Olive oil
The backbone of most beginner recipes. Pomace works and traces faster; plain supermarket olive oil is fine.
- Coconut oil, 76°
Provides hardness and big bubbly lather. The standard solid-at-room-temperature type.
- A hard fat: palm, tallow, or lard
Adds hardness and creamy lather. Lard and tallow are inexpensive and behave beautifully; sustainably sourced palm is the vegan equivalent.
- Castor oil
Five percent transforms lather. A little goes a long way - above about 10% bars turn sticky.
- Shea or cocoa butter
Optional luxury. Adds hardness and a creamy feel.
Colour, scent, and additives
Skip all of this for your first batch. An unscented bar is a good bar.
- Fragrance or essential oils
Check each one's maximum usage rate with the supplier. Some accelerate trace, some discolour, some rice. Essential oils have usage limits too.
- Clays (kaolin, French green, rose)
One to two percent of oil weight. Adds slip, gentle colour, and helps anchor scent.
- Micas and oxides
Soap-safe colourants. Disperse in a little oil first or you'll get speckles.
- Activated charcoal
Half to one and a half percent of oils for grey through black.
- Colloidal oatmeal, honey, milk powder
Gentle additives that add creaminess. Sugars in honey and milk make the batter heat up, so keep things cool.
- Sodium lactate
A teaspoon per pound of oils in the cooled lye solution makes for a harder bar that unmoulds sooner.
Cleanup and curing
The unglamorous half nobody photographs.
- Paper towels or newspaper
Wipe raw batter out of bowls before washing. Sending caustic grease down the drain is bad for the plumbing and the water.
- Curing rack
A baking rack, a shoe rack, or slatted shelving. Bars need airflow on as many sides as possible for four to six weeks.
- Parchment or freezer paper
For lining moulds and resting cut bars on.
- Labels and a notebook
Write down what you did while it's fresh: temperatures, how fast it traced, what you'd change. Lye.rs stores notes with each recipe for exactly this.
Ready to mix
Work out your lye and water for whatever oils you've got, then follow the method on the Learn page. The Classic Trinity in the recipe library is the usual first batch.
Equipment guidance, not a safety certification. Read your lye supplier's data sheet, and work at your own risk.