Turning Soap Scraps into a New Bar of Soap (Hand-Milled Soap)

Today I'm sharing a recipe with you that I use all the time! I always have soap scraps and shreds around my house, and I don't like the little pieces to go to waste. Most of the time I put my scraps into a linen soap saver bag (you can find them HERE) but sometimes I save the scraps until I have enough for a project.

And that project is making hand-milled soap!

This is also a great soap project to do with kids, as there is no lye involved in this process! So without further delay, here's my process for turning soap scraps into a new bar of soap:

You'll need:

-a cutting board

-a box grater (or sharp knife)

-microwave safe bowl

-a spatula

-measuring cups or kitchen scale

-a silicone mold (or any heat safe container)

-distilled water

-essential oils (optional)


Step 1: 

Grate or chop your soap scraps as small as possible. This will help your soap soften and blend better later on. If you plan to grate a lot of soap, consider setting aside a grater specifically for soap. Soap can dull the blades of a nice kitchen grater, and you may not want to use your best equipment for this project. Thrift stores often have box graters available! 

Step 2: 

Measure out your soap either on a scale or with measuring cups. Use 2 parts soap to 1 part water. Pour soap and water into a microwave safe container. (for example, if you have 1 cup of soap scraps, you'll only need 1/2 cup of water) 

Step 3:

Microwave your soap on high in 30 second increments. After every 30 seconds, stir your mixture thoroughly. Eventually, it should start to look gloopy. Adjust the amount of water as needed. You may need to pour off some of the water. 

Step 4:

Once your soap starts to resemble a gloopy bowl of oatmeal, it's time to pour it into your mold. At this point, if you want to add a scent to the soap, you can add a few drops of your favorite essential oil. Stir in thoroughly, and then pour your soap into the mold. I use silicone molds because they are easy to clean, and the soap pops out easily. But you can use almost anything! Some people like to use recycled food containers. You can also line a pan or another container with parchment paper, and pour the soap into that. 

Step 5: 

Let your soap set up in the mold until it is hard enough to remove. Then find a well-ventilated area (out of direct sunlight) and let your bar of soap sit for about 4-5 weeks. This lets the extra water evaporate out of the bar, and will give you a harder, longer lasting bar. If you're impatient, and you don't mind squishy soap, you can technically use your hand-milled soap right away. After all, there is no active lye in this process that needs to saponify. 

Step 6:

Enjoy your own hand-milled bar of soap!!

Some pro tips:

-Hand-milled soap works best with handmade soaps. Standard commercial bars don't cooperate quite as well. 

-Essential oils are highly concentrated, and some can irritate the skin. Avoid oils like cinnamon or clove, and only use oils that you have used safely before.

-If you want to change the color of the soap, feel free to mix in some food-safe colorants like cocoa powder, or activated charcoal powder. Cosmetic-grade clays like rose clay, or French green clay can also add some nice color.

Final Note:

This isn't the most beautiful soap. My hand-milled soap is almost always this shade of gray, and personally I think it looks like a slab of concrete. However, it's for my own personal use at home, and what it lacks in aesthetics, it more than makes up for in function!  You could absolutely sort scraps by color and make several lovely soaps. But the goal of this project is to provide a super easy method for using up scraps of soap :)

Until next time,


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