DIY Silicone Mold

There are different methods for creating food- and cosmetic-safe silicone molds that include the 1) starch and 2) soap methods. Select a method based on certain desired characteristics of the mold. For instance, if you need an extremely flexible mold that can be peeled away from a hard object with much ease and also one to capture very fine detail, the soap method is a good fit. Conversely, if you need a mold that is very firm and strong, whose structure can remain (largely) unchanged even when filled with water, the starch method is ideal. I particularly like the starch method because of its versatility. Specifically, adding oil as an option provides considerable flexibility without compromising the strength too much. I enjoy using this method for making my own loaf-shaped molds for DIY soap making.

Items for Making a DIY Silicone Mold (Corn Starch Method):

• the object to be used for creating a silicone mold
• Corn starch, an amount that is very roughly 50% of the silicone
• Gloves, like rubber gloves, NOT latex because the silicon sticks to latex.
• Silicone, 100% pure ~  . The entire tube of 280 ml sufficed for a soap mold with a surface area of 94 square inches (using a stick blender box of 3*3*14 inches. my mold also small tabs on its 4 sides).
• Small strip of cling wrap or plastic. This can be used to seal off the tip of the silicone tube. Most tubes continue to ooze silicone after you have squeezed the amount you want. 
• caulking gun (if the silicone comes in a caulking tube)
• Oil, a dash. any type that includes sunflower oil, baby oil or pure mineral oil ~ (to allow the mold to stretch and flex, characteristics that make it considerably easier to handle the silicone mass). Since the process if messy, you may want to put the oil in a small dish aside. (optional)
• Colour, mixing container and pop-cycle stick (for stirring). Examples include food dye or acrylic paint. Examples of a mixing container include a plastic cup or bowl. (optional)
• Flat working surface covered with a protective barrier like parchment paper --or-- a mixing bowl --or-- for a no-mess way of containing and kneading the silicone dough, a zip lock bag from which the mass can be piped through a new hole. NB however that you will lose a bit of the dough to the sides of the bag.
• Rolling pin. This is useful for making log soap molds. (optional)
• A ruler. This will come in handy with the rolling pin. (optional)
• Good ventilation
• Advanced. mineral spirits, to thin out silicone. Mineral spirits are usually used for cleaning up interior jobs. You must however combine all ingredietns as follows: 1 part silicone, 1 part corn starch and 0.5 part spirits. (optional)

Steps for Making a DIY Silicone Mold (Corn Starch Method):

1. Prepare the mold object on the work surface. There is a short time window to work once the silicone is ready.
2. (optional). To have an even colour, put the silicone in a small container aside (like a plastic cup or bowl). Mix in the colorant. You may combine the colour by adding it on top of the silicone when adding the silicone to the corn starch later.
3. Place a layer of corn starch onto the work surface.
4. Make a depression in the corn starch
5. Pour the silicone into the depression and onto itself. Do not spread the silicone flat as it can become over-saturated with cornstarch and hard to collect into a single mass.
6. Dust more corn starch on top of the silicone
7. Be prepared to work quickly since corn starch accelerates the hardening process of the silicone.
8. Oil the finger tips of your gloves and or work a small amount into the silicone dough. The more oil you use, the more the oil will allow the mold to stretch and may help in un-molding creations (like soap) without cracking the edges of the mold.
9. Knead until the mass feels like bread dough. Do not worry about the kneading all of the starch. The excess should be left behind.
10. Add more oil as needed.
11. Without delay, place the mass over the shape and spread it as required. If need be, you can pinch pieces from one area to add to others. Pay special attention to reinforcing corners because they are more susceptible to tearing.
12. NB. Create a thick lip which you can use for making it easy to release your creation (soap, concrete shape, etc) from the mold.
13. As an option, create slits in the lip to anchor vertical separators
14. De-mold when the mass springs back when squeezed.

Items for Making a DIY Silicone Mold (Detergent Method):

• Silicone, 100% pure ~  
• Small strip of cling wrap or plastic. This can be used to seal off the tip of the silicone tube. Most tubes continue to ooze silicone after you have squeezed the amount you want. 
• A bucket or other water holding container
• Water 
• Detergent (dishwashing liquid. I do not believe that soap powder will work)
• A smooth surface. Examples include a plastic cutting mat, plastic projector sheet
• Colour, mixing container and pop-cycle stick (for stirring). Examples include food dye or acrylic paint. Examples of a mixing container include a plastic cup or bowl. (optional)
• Gloves, like rubber gloves, NOT latex because the silicon sticks to latex.
• Flat working surface covered with a protective barrier like parchment paper- or - a mixing bowl
• Good ventilation

Steps for Making a DIY Silicone Mold (Detergent Method):

1. Prepare the mold object on the work surface. There is a short time window to work once the silicone is ready.
2. Make very soapy water into the water container. The soapier the water, the less likely the silicone will adhere to the gloves (or hands) when you knead it.
3. In a colour mixing container aside, place the silicone, add the colour and then combine the 2 homogeneously. (optional)
4. Squeeze the silicone into the water
5. Pull all the silicone together
6. Knead the silicone while keeping it under water. Knead until the mass stops being stringy and has sufficient malleability. 
7. Without delay, place the mass over the shape and spread it as required. Be especially quick to proceed to this step if you need to capture a lot of fine detail. If need be, you can pinch pieces from one area to add to others. Pay special attention to reinforcing corners because they are more susceptible to tearing.
8. NB. Create a thick lip which you can use for making it easy to release your creation (soap, concrete shape, etc) from the mold.
9. As an option, create slits in the lip to anchor vertical separators
10. Spread the silicone mass over the mold.
11. De-mold when the mass springs back when squeezed.

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