How To Make Cold Process Soap: A Beginner's Guide to DIY Natural Soapmaking

Cold process soap making allows you to create gorgeous, handmade glycerin soaps entirely from scratch. By making your own soap, you can fully control the ingredients to create customized bars packed with skin-nourishing oils, beautiful colors and fragrances, and a gentle cleansing experience free of harsh detergents.

Though it requires some special equipment and safety precautions, cold process is not overly complex or difficult with the right guidance. In fact, it can be a fun, rewarding hobby and creative outlet! This beginner's guide will walk you through every step of the cold process method, from choosing your ingredients to cutting the final soap bars. Let's dive in to the wonderful world of from-scratch soapmaking!

Getting Started: Equipment and Ingredients You'll Need

Before making your first batch, it's important to stock up on some basic soapmaking supplies. Having the right gear and ingredients on hand will make the process smooth and safe. Here's an overview of the key items you'll need:

Protective Equipment

Goggles and gloves: Lye can be very irritating to the eyes and skin, so eye protection and gloves are a must when handling the raw sodium hydroxide. Go for goggles that fully seal around the eyes, and rubber gloves that cover the wrists.
Mask (optional): Some soapmakers choose to wear a particle mask as extra protection from breathing in lye dust. This is especially recommended if making large batches frequently.
Long sleeves and pants: Wear clothing that covers the arms and legs to avoid skin contact with splashes or spills.

Tools and Workspace

Digital scale: Precisely weighing your ingredients is vital for soapmaking. Look for a scale that measures in grams with a capacity of at least 4-5 lbs.
Silicone spatula: This heat-resistant rubber spatula will help incorporate the lye solution into the oils and assist with mixing.
Stick blender: A stick blender allows you to quickly reach "trace" (the point where the soap thickens to leave a trail behind when drizzled). Budget models work fine for soap.
Loaf mold: This mold produces easy-to-cut bars. Wood, silicone, and plastic molds all work well.
Mixing containers: Heatproof containers for the lye solution and oils, ideally stainless steel or plastic.
Table and surfaces: Cover your work area with newspaper or butcher paper in case of spills. Work in a well-ventilated space.

Soapmaking Oils and Butters

Coconut, palm, olive, sunflower oils: A combination of saturated and unsaturated oils creates a hard, moisturizing bar. Run recipes through a lye calculator before using.
Shea or cocoa butter (optional): These add skin-nourishing vitamins without becoming greasy. Limit to 10-15% of your oil weight.
Castor oil (optional): Just a spoonful adds great bubbly lather. Use sparingly at 5% or less, as it can make soap sticky.

Lye and Water

Sodium hydroxide lye: Also called NaOH, this caustic base is diluted with water to create the chemical reaction that forms soap. Only use lye specifically formulated for cold process soap.
Distilled water: Tap water can create soda ash on bars. Distilled gives you clear, clean-looking soap.
Lye safety equipment: Have a dedicated lye container, and work carefully to avoid spills. Never breathe in lye fumes or let lye touch bare skin. Keep children and pets away.

Additional Ingredients

Essential oils: Not required, but 5-10 drops of essential oil per pound of base oils makes a lovely scented bar.
Colorants: Use natural colorants like clays or herbs, or liquid soap dyes formulated for cold process.
Additives (optional): Ingredients like oatmeal, coffee, rose petals, etc. can be mixed in for exfoliation or visual appeal.

Step 1: Creating the Lye Solution

Once you have all the ingredients and equipment, it's time to get soaping! First up is preparing the lye solution, which will later get combined with the oils to form soap. Here's the process:

Weigh the lye. Use your digital scale to carefully measure out the amount of sodium hydroxide lye specified in the recipe. Remove rings and watch; lye can react with metal.
Measure the water. In a separate container, carefully measure out the distilled water called for in the recipe. Never add water to lye; always add lye to water.
Combine and stir. Put on your safety goggles and mask. Slowly pour the lye into the water while stirring constantly with a silicone spoon or lye spatula. Never lean over the container, as the mixture will create harsh fumes.
Cool the mixture. Allow the lye solution to cool until it is clear and reaches 90-100°F. This brings it to the ideal temperature to combine with the oils later.

Stirring regularly, it should take about 30-60 minutes to cool sufficiently. You want the lye solution and oils to be within about 10°F of each other before combining. A thermometer comes in handy for checking temperatures.

Note: Always add lye to water in a well-ventilated space and avoid breathing the fumes! If you notice any solid lye beads that won't incorporate, allow more time to cool and stir occasionally. Prepare this solution the day before soaping if you want a head start.

Step 2: Prepare the Oils and Butters

While your lye solution rests, you can move on to melting and combining your oils and butters. Here are some tips:

Weigh out each oil called for in the recipe using a digital scale. No need to be exact to the gram, but close measurements are best.
Melt any hard oils or butters like coconut oil, shea butter, or palm wax in a double boiler or microwave at low power. Heat just until melted and no hotter.
Add liquid oils like olive or sunflower oil straight to your mixing container. Measure essential oils if using.
Once all oils are melted and combined in the mixing bowl, let them also cool to 90-100°F, stirring now and then. Use this time to clean up any dishes used for melting the hard oils.

Having both the lye solution and oils at about 95°F is ideal. This warm (not hot!) temperature allows the soap to get to trace faster once combined. If the solutions cool off too much, simply reheat briefly until warm.

Step 3: Combining the Mixture and Reaching Trace

Now for the fun part - mixing the lye water and oils together! Have your stick blender plugged in and ready to blend. Here's the process:

Slowly and carefully pour the lye solution into the oils, angling the pour along the side of the bowl to avoid splashing.
Gently stir with your spatula to fully incorporate the lye into the oils before blending. This prevents pockets of high pH that can accelerate trace too quickly.
Start stick blending in short 5-10 second bursts. The mixture will start to thicken up into a creamy emulsion.
Continue blending in bursts until trace. Trace is when the mixture leaves a visible "trace" on the surface that holds its shape for a few moments when you drizzle it. This can take 2-5 minutes. Don't blend so long that it accelerates trace time.
If adding clays, flower petals, oatmeal, or other add-ins, do so after tracing and stick blend briefly to fully incorporate them.
Lastly, add essential oils or fragrance if desired and give it a final stick blend to fully mix in. Work quickly once adding scents to prevent acceleration.

And that's it - once at trace, your soap is ready to be poured into molds!

Step 4: Pouring and Insulating the Soap

Now that the soap has emulsified and thickened to trace, swift action is required to get it into the mold before further thickening prevents pouring. Follow these steps:

If using a wooden mold, line it with parchment paper or a silicone mold liner to help easy unmolding later. If using a silicone mold, no liner is needed.
Carefully pour your traced soap batter into the prepared mold. Tap the sides of the mold gently on the counter to release any air bubbles.
Use your spatula to scrape every last bit of soap out of the mixing container - don't waste any!
Once filled, place the mold on a flat surface. Insulating it helps prevent cracking and cold spots as the soap cures and releases heat from the chemical reaction. Here are some insulation options:
1. Place it inside an insulating soap mold box, covered securely.
2. Wrap the mold fully in towels or blankets.
3. Partially fill a cardboard box with towels, set the mold inside, and cover the top.
Allow the insulation to trap heat and prevent cooling for at least 24 hours while the soap cures. Resist peeking!

If poured correctly at trace, the soap should gel fully inside the warm mold and develop a smooth, even appearance throughout the bars. Well-insulated soap won't overheat or volcano out of the mold.

Step 5: Unmolding, Cutting, and Curing the Soap

You've mixed, molded, and insulated your soap - but the final steps are important for perfect bars! Follow these guidelines:

Unmold within 24-48 hours. Carefully peel back the liner or turn over the mold to release the finished soap loaf. It should slide out cleanly if left to cure long enough inside the warm mold.
Cut into bars. Use a stainless steel knife or soap cutter to slice the loaf into uniform bars. Allow the bars to air dry for a few hours before moving them.
Cure the soap bars. Stack the soap loosely on a drying rack or cardboard box, allowing air circulation. Cure time can vary from 4-6 weeks. Longer cures yield harder, longer-lasting bars.
Monitor periodically. Check for excess moisture and signs of soda ash (a harmless white powder). Gently wipe any ash away with a soft cloth.

And that's it - your cold process soap is ready to use for an amazing lather and clean rinsing feel! With the right recipe and technique, handmade soaps make wonderful gifts or sale products too. Just wait the full 4-6 weeks cure time for nicely hardened and mild bars.

Troubleshooting Common Soapmaking Problems

Even experienced soap makers run into issues occasionally while perfecting cold process recipes. Here are some common problems and solutions:

Accelerated Trace

Cause: The soap batter seized up and thickened to trace too quickly, typically within 1-2 minutes. This can happen due to overheating, adding too much liquid, or high water dilution of the lye solution.

Solution: Let your lye solution and oils cool more before mixing, stick blend less, use chilled distilled water, and avoid water discounts above 30%.

Partial Gel

Cause: The soap loaf or certain parts did not fully complete the gel phase, where the batter heats up and becomes more translucent. Lack of insulation is the most likely cause.

Solution: Fully insulate molds for at least 24 hours. Wrap loosely with towels or use an insulated soap mold box.

Soda Ash

Cause: White sodium carbonate powder that forms on the soap surface. Usually caused by soaping at too low a temperature or contact with humid air before cure finishes.

Solution: Make sure to soap warm, around 95-100F. Wipe away ash with a damp cloth. Adding castor oil or sodium lactate can also help prevent soda ash.

Separation

Cause: The oils start separating out of the soap batter after mixing, leaving pockets of oil. Can be caused by not fully incorporating oils, soaping too hot, or adding too many soft oils.

Solution: Stick blend thoroughly to trace, soap under 110F, limit liquid oils to 30% or less of the recipe, and don't insulate the mold more than 48 hours.

With some trial and error, troubleshooting, and recipe tweaking, you'll be whipping up gorgeous batches of creamy cold process soap with confidence!

Take Your Soapmaking Skills Even Further!

Once you've mastered the basics of cold process soapmaking, the possibilities are endless for customizing your own bar recipes. Try out these advanced techniques for stunning creations:

Swirls: Add eye-catching swirls throughout the soap loaf using multiple colors and by layering and swirling with a spatula or chopstick.
Natural colorants: Infuse your soap with botanicals like rose clay, activated charcoal, spirulina, turmeric, and essential oils for naturally colored bars.
Embeds: Press delicate objects like dried flowers, jojoba beads, or soap curls into the top of the soap mold right after pouring.
Layers: Pour differently scented batters into the mold in layers, one after the other, for a "lasagna loaf" effect. Create stripes by pouring each layer from higher up.
Texture: Add natural exfoliants like oats, sea salt, coffee grounds, etc. to create a scrubby bar soap. Or make a creamier lather with milks or purees.
Mold shapes: Pour into unique silicone molds like seashells, pebbles, or geometric shapes for fun figurine soaps. Or carve a loaf into custom shapes.

The creativity involved in designing your own cold process soap recipes and techniques is limitless. And nothing beats the satisfaction of washing up with a bar of handmade soap you crafted yourself using nourishing ingredients.

We hope this beginner's guide gives you the confidence to venture into the fulfilling hobby of soapmaking. Just be sure to take the necessary safety precautions when handling lye, and have fun getting creative with colors, scents, and designs!

Frequently Asked Questions About Cold Process Soapmaking

Interested in trying your hand at making cold process soap? Here are answers to some of the most common questions beginners have when starting out.

What is the difference between hot process and cold process soaps?

The main difference lies in the saponification method.

Cold process involves combining lye water and oils at warm temperatures around 100°F. The soap then thickens and cures over 24-48 hours in the mold as the chemical reaction completes. This results in a gentle, moisturizing bar.
Hot process uses external heat sources after trace to speed up saponification. The soap batter is cooked in a crockpot or on the stove at 130-160°F for 1-2 hours until it reaches a vaseline-like consistency. The bars harden faster after molding. Hot process soaps tend to have a rustic, homemade look.

What oils are best for beginners to use in cold process soap recipes?

When first starting out, choose easy-to-work-with oils like:

Olive oil (for moisturizing bars)
Coconut oil (for bubbly lather)
Sunflower, avocado, or sweet almond oils (for a smooth texture)

Avoid tricky oils like castor, palm, or neem oil until you gain more experience with how different oils influence trace times, hardness, and lather. Steer clear of animal-derived tallow or lard as a beginner as well. Stick to all-vegetable oil recipes first.

Can I design my own cold process soap recipe as a beginner?

It's best to follow tried-and-true recipes from experienced soapmakers when you first start out. Creating your own recipe requires an understanding of how each oil contributes to the final bar characteristics.

After several successful batches using proven recipes, you can start customizing your oil combinations and additives once you become more knowledgeable. Refer to online lye calculators to safely formulate your own recipes.

How long does cold process soap need to cure before use?

Curing time ranges from 4-6 weeks on average. Curing allows time for the last bit of saponification to complete and for excess moisture to evaporate. This results in a harder, longer-lasting bar of soap.

Using soap too soon can result in a slimy-feeling bar that dissolves quickly. Test your soap at 4 weeks - if it still feels soft or sticky, give it 1-2 more weeks. Well-wrapped bars can be cured for several months.

Can I rebatch a failed or old batch of cold process soap?

Yes! Rebatching lets you salvage old or unsightly bars of cold process soap by re-melting them, adding oils or milk, and repouring into molds. Grate or chop the soap into small chunks first. Melt together in a crockpot or double boiler with a bit of water, milk, or fresh oils. Stir regularly as it melts, then pour into molds and allow it to reset before cutting into bars.

How do I create fun color designs in my cold process soap bars?

Some options for colorful swirls and designs include:

Blend in natural colorants like clays, activated charcoal, etc.
Add liquid soap dyes specially formulated for cold process either before or after trace.
Reserve some uncolored batter, then pour colored batter into the mold first for a marbled look.
Layer batters of different colors in the soap mold one after the other.
Spoon or pipe small amounts of colored batter into white batter for a confetti or dot effect.
Swirl colors together with a chopstick or skewer after pouring.

Get creative with colors and designs - just be sure any soap dyes or mica powders you use are skin-safe and designed for cold process application.

What should I do if my soap seizes up and thickens to trace too quickly?

"Acceleration" happens when soap comes to trace within 1-2 minutes. Try these fixes to slow down trace next time:

Soap at cooler temperatures around 85-90°F
Use chilled lye water and distilled ice water
Don't let your lye solution go above 130°F
Stick blend for shorter intervals
Avoid fragrance or essential oils that are known to accelerate trace

Can I sell the cold process soap I make at home?

You can, but be aware of the legalities involved! Look up your state's cottage food laws to see if a home-based soapmaking business is allowed. Most states require the use of a commercial kitchen if selling soaps.

Liability insurance, packaging and labeling regulations, and ingredient safety testing may be required as well. Assess the time and financial commitment before selling your soaps - but by all means, share the soapmaking love by gifting your creations!

We hope these tips help answer some of the most frequently asked questions about making luscious cold process soap bars! Don't be afraid to experiment and find the techniques that work best for your artistic vision.