Soap making molds come in various shapes, sizes and materials. It’s crucial to consider what kind of mold you’ll be using when designing a soapy project. The mold will determine how big your batch needs to be, and may influence ingredients and cure time. One of the most popular soap mold options is a silicone mold. They are easy to clean with no lining necessary and come in a variety of shapes and sizes. Other mold options include recycled containers, plastic and wood molds. Each have benefits that may affect your soaping experience.

Silicone Molds
Pros: Easy to unmold soap with flexible material, easy to clean, no need to line mold, long lasting, professional looking bars
Cons: Soap takes slightly longer to unmold, soap can speckle with bubbles if soap overheats

Silicone molds are extremely popular due to their ease of use. Sturdy yet flexible, silicone molds make unmolding both cold process and melt and pour soap easy. The key is to break the airlock by gently pulling away the sides of the mold from the soap. If you experience any resistance when removing cold process soap, stop and give it a few more days in the mold. It’s not worth it to tear the sides or bottom of your project!

Soap does take longer to harden in silicone molds because there is no air in contact with the soap. Sodium lactate is a key additive to use when working with silicone molds. Sodium lactate is a liquid salt that helps produce a harder bar of soap that lasts longer in the shower. Sodium lactate also helps the soap harden faster in the mold. This means that instead of waiting 3-4 days to unmold your project, you can often unmold the very next day! We recommend adding 1 tsp. of sodium lactate per pound of oils in your recipe to cooled lye water. Click here to read more about sodium lactate, and how to use it in your projects.

In addition to easy unmolding, silicone molds are easy to care for. After removing your soap from the mold, hand wash the silicone mold with hot water and dish soap. Allow to dry and the mold is ready to use for your next project! While silicone molds are sturdy, we do not recommend placing them in the dishwasher. Also avoid any harsh scrubbing materials such as copper sponges, as they may scratch the glossy finish inside. Click here to read more about caring for molds.

Recycled Molds
Pros: Create unique shapes, cost effective, eco friendly
Cons: Shapes not consistent, may need to line mold, mold may only be good for one use

Just about any container can be turned into a soap mold with proper lining. If the container is plastic, the soap can be poured directly without lining. Popular options include yogurt containers, pudding cups and tofu containers. Cardboard milk containers are also a good option, as the inside is normally lined with a nonstick coating. Check out the How to Recycle Your Recyclables post for more ideas. Recycling objects and boxes in your home is a great way to save money on molds and create eco-friendly and unique looking bars.

One negative aspect of recycled molds is they may not be very sturdy, and may produce bars that are not completely straight or uniform. If you are looking to create professional looking bars consistently, other mold options are better choice. The container should not be used for food storage once used to make soap. Depending on the sturdiness of the container, it may only be good for one soaping recipe.

Most recycled containers will need to be lined with freezer paper to ensure the soap does not stick. Lining also helps ensure the soap does not leak. For example, both the Creamy Orange Cold Process Soap and the Simple & Gentle Cold Process Soap tutorials were created in a USPS Medium Flat Rate Box. If the soap was poured directly into the cardboard, the soap would stick to the box. To prevent this, freezer paper was used to line the box. The How to Line Any Mold blog post has tips on turning any box into a proper soap making mold.

Metal or glass containers are not recommended for cold process soap molds. One reason is they are extremely hard to remove your soap from. If using rigid molds, they should be lined with freezer paper…otherwise you may never get the soap out! The other reason is that lye reacts with many metals, including aluminum, tin and zinc. The sodium hydroxide lye reacts with the metal releasing hydrogen gas which is very dangerous. Avoid all metal containers for soaping with.

Wood Molds
Pros: Easy to insulate/gel phase, long lasting, produces large batches of soap, professional looking bars
Cons: May need to line mold, can soften over time when exposed to raw soap from drips & normal use, prone to overheating

Another popular soap mold option are wood molds. They are sturdy, cost effective and act as great insulators for cold process soap. They can also last for years and years with proper storage and care. Bramble Berry wood molds are made out of top grade Birch plywood that is both sturdy and durable, click here to learn how to care for them.

Wood molds also need to be lined with freezer paper to avoid the soap from sticking to the mold. To make this process easier, many of the Bramble Berry wood molds have silicone liners available. When lining any mold, keep in mind that freezer paper is much different from wax paper. Freezer paper is sturdier, and will not melt under high temperatures.

A wood mold is used in the Blue Rain Drop Swirl Cold Process to insulate the soap. Don’t forget to line your wood molds!

One of the best features of wood molds is they insulate the soap well. This makes it easy to achieve a complete gel phase throughout the soap. It’s important to keep this in mind when insulating wood molds; because they insulate the soap naturally, placing the mold on a heating pad may not be necessary. If you want to avoid gel phase completely, you may want to place the mold and soap into the fridge or cool place. Learn more about gel phase and when to insulate your soap in this post.

Plastic Molds
Pros: Wide variety of shapes and designs, cost effective, great for small batches, professional looking bars
Cons: Can be difficult to unmold, requires more time to unmold, prone to soda ash, difficult to make large production batches

Best suited for melt and pour, plastic molds can also be used for cold process soap. Plastic molds come in a wide variety of shapes and sizes. In fact, Bramble Berry has more than 400 plastic molds to choose from. If you can’t imagine it…there is probably a plastic mold for it! The majority of plastic molds are individual cavity size. The smaller size means that the molds do not insulate the soap as well as large slab or loaf molds. We don’t recommend placing plastic molds on a heating pad, as they can melt or warp if they get too hot. Instead of using gel phase to help prevent soda ash, you can spritz the soap with 99% isopropyl alcohol every 15 minutes for an hour. That helps create a barrier to protect the top of the soap. You can also decrease the superfat level to 3% or water discount at 10%. Read more tips for preventing soda ash here.

The trick is that cold process soap can be a little bit tricky to remove from plastic molds. Cold process soap can require up to a week to unmold from plastic molds. If using a plastic mold for your cold process project, we recommend using a large amount of hard oils (palm oil, coconut oil, cocoa butter, etc) to help the soap harden. Adding sodium lactate also makes a huge difference; check out the Unmolding Cold Process Soap from Plastic Molds for more tips and an experiment with hard/soft oils and sodium lactate.

Sometimes it takes a little time to find the right type of mold for you. Personally, silicone molds have become my new go to after years of using wood molds. But if I want my soap to go through gel phase, wood molds are still my favorite. When using plastic molds I make sure my recipe contains solid oils, and I always use sodium lactate. When teaching friends how to soap, I usually recommend trying out the craft with recyclables first, just to make sure they enjoy the process. Each mold has its positives and negatives, and so much just depends on personal preference! =)

What kind of molds do you prefer? I would love to hear your thoughts in the comments below. 

The post Back to Basics: How to Choose a Soap Mold appeared first on Soap Queen.

First and foremost, patience is key. While soap in silicone or wood molds is ready to unmold as early as 3-4 days, cold process soap in plastic molds can take up to 2 weeks. If your soap is still soft when you try to unmold it, it can leave drag marks or holes. Some of the details may be left in the mold as well. So, if your soap doesn’t want to come out of the mold, let it sit for another day or two.

The recipe you use plays a huge role in determining how long the soap needs to stay in the plastic mold. Soap with a lot soft oils – oils that are liquid at room temperature – takes longer to harden. Soap with mostly soft oils, like olive oil and sweet almond oil, can take even longer than 2 weeks to unmold. Also, some of the details may not be as clear. Recipes with a lot of hard oils – oils that are solid at room temperature – will pop out of the molds faster. Hard oils include coconut oil, palm oil, cocoa butter and shea butter. Read more about hard and soft oils in the Formulating Cold Process Recipes post.

Sodium lactate is incredibly helpful when unmolding cold process soap from plastic molds. Sodium lactate is the sodium salt of lactic acid. Adding 1 tsp. of sodium lactate per pound of oils to your cooled lye water speeds up the unmolding process. It also produces harder, longer-lasting bars of soap. I use it every time I make cold process soap in plastic molds. To learn more, click through the Sunday Night Spotlight: Sodium Lactate.

You’ve made a recipe with mostly hard oils. It’s been in the mold for at least a week, and it has sodium lactate. What now? To unmold, pull on the sides of the mold. This breaks the airlock. Then, flip the soap mold over and press gently on the back of the cavities with your thumb or the heel of your hand. If the soap doesn’t want to come out, pop it in the freezer for about 10-15 minutes. Don’t leave it in there too long, or the plastic can crack. If the soap still isn’t budging, let it sit in the mold another couple of days. Remember, patience is key!

To demonstrate how different recipes perform, two cold process recipes were made in the Sand Dollar Mold. One of the recipes consisted of 70% soft oils, and the other recipe consisted of 70% hard oils. We then tested the same two recipes, but the second time we added 1/4 tsp. of sodium lactate to the lye water.

Soft Oils Recipe 
.5 oz. Coconut Oil (15%)
2.5 oz. Olive Oil (70%)
.5 oz. Palm Oil (15%)
.5 oz. Sodium Hydroxide Lye
1.2 oz. distilled water
Optional: 1/4 tsp. Sodium Lactate

Hard Oils Recipe
1 oz. Coconut Oil (30%)
1 oz. Olive Oil (30%)
1.4 oz. Palm Oil (40%)
.5 oz. Sodium Hydroxide Lye
1.2 oz. distilled water
Optional: 1/4 tsp. Sodium Lactate

Soft Oil Recipe
When unmolding the soap made with sodium lactate (shown on the left), they actually fell out of the mold! The soap is nice and firm, and all the details stayed on the soap. The soap on the right, without sodium lactate, didn’t fare as well. As you can see, several of the details are missing from the soap. There are also drag marks and holes.

Hard Oil Recipe
Again, the soap made with sodium lactate (shown on the left) fell out of the mold. It is firm and beautifully detailed. While the soap without sodium lactate did a little better than the recipe with mostly soft oils, there are still holes. One of the soaps is also missing a part of the sand dollar.

Experiment Results
The main takeaway from this experiment is sodium lactate is your friend when it comes to making soap in the plastic molds. With sodium lactate, both the hard and soft recipes came out of the mold easily after one week. The soft oil recipe without sodium lactate performed the worst – the most soap stuck to the mold and the design was extremely damaged. Soap made with hard oils and no sodium lactate did a little better, but the design was still damaged. If you choose not to use sodium lactate and want to use a plastic mold, be prepared to wait more than one week to successfully unmold your soap.

If you don’t have sodium lactate, you can use a salt water solution to harden your soap. To make the solution, mix 1 teaspoon of regular table salt into 1 ounce (by weight) of warm distilled water. Stir until the salt is fully dissolved. We recommend 1 teaspoon of salt in 1 ounce of water per pound of soap. Make sure to discount the salt water solution from your liquid amount. Then, add the solution at trace. The salt water solution was used in the Palm Free Vertical Twist Tutorial with great results.

We don’t recommend using any of our clear plastic molds for hot process soap. They can only withstand temperatures up to 145° F. Hotter temperatures can morph the plastic. The heavy duty molds can withstand temperatures up to 165° F, but may warp in the oven. The heavy duty molds work for rebatch, as seen in the How to Make Rebatch Soap video on Soap Queen TV. Because the molds are heat sensitive, we do not recommend gelling cold process soap in them. Instead, you can let your soap dry at room temperature.

Don’t feel like waiting? Melt and pour soap is a great option! It is ready to unmold a couple hours in the mold, or up to 12 hours. Check out these melt and pour recipes made with plastic molds:

Top row, left to right: Mermaid Shell Melt and Pour, Movember Mustache Melt and Pour
Bottom row, left to right: Painting Soap with Mica Powder on Soap Queen TV, Rainbow Unicorn Melt and Pour

Do you use plastic molds for cold process soap? Do you have any tips for unmolding? I’d love to hear them!

The post Unmolding Cold Process Soap from Plastic Molds appeared first on Soap Queen.