I've started to make soap at home few years ago.

When I was testing the waters to know whether or not I liked it, I didn't want to invest money in expensive gear. I started using Pringles cans as molds, but later on my soap-maker journey, I've decided to build my own mold. After a few iterations, I came up with the design I will describe here.

This mold yields approximately a 50 by 100 by 257 millimeter bar when using 1 kilogram of oil. It is big enough to double all my recipes if needed.

Supplies

You will need:

a 2-ply cardboard sheet (thickness of 7 millimeters)
painter tape (can be replaced by regular tape)
double sided tape (can be replaced by glue)
a pencil
a ruler
a triangle
a cutting mat (optional)
a cutting knife
scissors

Step 1: Draw the Different Elements

The mold is made of 6 different elements. One for the box, two for the lid, and 3 for the base. Draw each element from the template on the cardboard. Below, you can find the original dxf file and a converted pdf file.

Note that you don't need to use colors as I did. There are here only to help you go through the following steps. The black lines are for cutting. The red lines are for scoring.

Note that all measurements are in millimeters and are made to use 7-millimeters 2-ply cardboard. If you use a different cardboard, you'll need to adjust all dimensions.

Step 2: Cut the Different Elements

Cut each element on the black lines identified in the template. Do not cut on the red line for now.

Step 3: Create the Hinges

Now, you need to score the cardboard on the red lines. Cut almost through the cardboard letting only the outer layer of the cardboard untouched. The outer layer will be used as hinges.

Note that you need to create the four hinges on the same side of the cardboard.

Step 4: Reinforce Hinges

As they are made of the outer layer of the cardboard, hinges are pretty weak. Add a layer of painter tape to make them stronger.

To do so, open the hinge to expose the internal layers of the cardboard. Then add the painter tape on the exposed edge. Then close the hinge to make everything stick together.

Note that the tape overlaps in the corners.

Step 5: Build the Lid

Add a piece of double sided tape on the smaller element. Then attach it to the center of the bigger element.

Step 6: Put Everything Together

Insert the small base elements into the big base element. Fold the box and insert it in the base. Put the lid on top.

Step 7: Use It

Before making a batch of soap, line your new mold with parchment paper. It will protect it.

Introduction: Cardboard Soap Mold With Lid and Base