Silicone molds are always very popular because they are easy to use and come off easily. On the market there are various shapes and sizes and in the most varied designs, but sometimes finding the most suitable one for a personalized object is impossible, so you have to make it yourself. To do this, you can always buy a kit for two-component silicone molds in the shop or save more and create your own "homemade" mold!
Steps
Method 1 of 3: Use Silicone and Liquid Soap
Step 1. Fill a basin with water
The water must be at room temperature, neither too hot nor too cold, and there must be enough of it for you to dip your hands into.
Step 2. Mix some liquid soap with the water
You can use virtually any type of liquid soap, including shower gel, dish soap, and hand soap. Keep stirring until the soap has completely dissolved.
- Plan to use about 1 part of soap in 10 parts of water.
- You can also use liquid glycerin. This will react with the silicone and cause it to thicken.
Step 3. Add some building silicone to the water
Buy a pure silicone tube at a DIY store (make sure it's not the quick-set one) and put some in the bowl. It must be enough to cover your item.
- Building silicone may also be labeled "silicone sealant".
- If the tube does not have a syringe, you will need to purchase a silicone cartridge gun, insert the tube and cut the end to pierce it.
Step 4. Work the silicone into the bowl
Put on a pair of plastic gloves and dip your hands into the bowl to collect the silicone in your fist and squeeze it. Continue to work it in the water until you feel it is no longer sticky. This will take approximately 5 minutes.
Step 5. Shape the dough into a fairly thick disc
First, make a ball of the dough by rolling it between your palms and then press it onto a flat surface with light pressure. However, the thickness must be greater than that of the object you want to mold.
If the silicone is sticky, wear gloves and work the surface with a thin layer of liquid soap
Step 6. Impress your object in the silicone
Impress the object into the dough (making sure that the motif you are interested in reproducing is facing down) and gently press the edges of the mold against the object so as not to leave gaps.
Step 7. Let the silicone harden
Silicone will never become rock solid, it will always be flexible. Simply wait a few hours for it to stiffen enough so that you can bend it without it getting damaged.
Step 8. Take the object out of the mold
Take the mold from the edges and fold it back to detach it from the object. This should come loose or pop out on its own, so flip the mold over to get it out completely.
Step 9. Use the mold
Fill the mold with modeling clay which you will then extract and leave to dry. You can also try using resin with this mold, but you will need to let it dry and harden before taking it out.
Method 2 of 3: Use Silicone and Corn Starch
Step 1. Squeeze some building silicone into a plate
Buy a pure silicone tube at a DIY store (usually the container is shaped like a syringe) and squeeze some into a plate that you will then throw away. You will need enough of it to cover the object you want to mold.
- Construction silicone can also be found with the "silicone sealant" label. Make sure it's not the quick-setting one.
- If it does not have a syringe, you will first need to get a gun for silicone cartridges, insert the tube and cut the end to pierce it.
Step 2. Pour the cornstarch into the silicone (in a 2 to 1 ratio)
If you can't find cornstarch, try using cornmeal or potato starch. Keep the box handy as you may need more.
If you want to get a more colorful mold, you can also safely add a few drops of acrylic paint because it will not affect the effectiveness of the mold
Step 3. Put on a pair of plastic gloves and knead the two ingredients together
Keep kneading until the silicone and cornstarch form a smooth dough. It may be dry and crumbly at first, but keep kneading, adding a little more cornstarch if it's too sticky.
There may be some corn starch left in the dish, but it doesn't matter: it means that the silicone is now saturated with it
Step 4. Form a disk by rolling the silicone
First, make a ball of the dough by rolling it between your palms. Then place it on a smooth surface and flatten it, compressing it slightly; the thickness must in any case be greater than that of the object you wish to obtain the mold for.
Step 5. Press the object you want to mold into the dough
Make sure you put it face down and that the part you see is the back. Then, with your fingers, press the edges of the mold against the object so as not to leave gaps.
Step 6. Wait for the silicone to dry
This operation will take about twenty minutes. When the dough has hardened, you will be ready for the next step. As you can see, the dough will still be flexible, but you will no longer be able to dent it or change its shape.
Step 7. Take your object out of the mold
Take the silicone mold by the edges and gently fold it back to detach it from the object, then flip it over to pop it out completely. If necessary, pull it out with your fingers.
Step 8. Use the mold
You can fill the mold with wet modeling clay which you will then extract and let it dry, but you can also pour some resin into it, let it dry and finally extract it. Use the same procedure used to extract the first object for the following ones as well.
Method 3 of 3: Use Two-Component Silicone
Step 1. Purchase a silicone mold making kit
You can find it in stores that specialize in modeling and mold making supplies and sometimes even in craft shops if they are well stocked. Many kits consist of two containers labeled "Component A" and "Component B". Sometimes you have to buy them separately instead.
Do not mix the two components yet
Step 2. Cut out the bottom of a plastic food container
Get a thin plastic food container that is inexpensive and, using a utility knife, cut the bottom without worrying if you are making a neat cut or poorly maintained. This will be the top of your mold.
Choose a container that is a little wider than the object you want to mold
Step 3. Cover the top of the container with strips of masking tape and make sure they overlap
Remove the lid of the container. Cut long strips of packing tape and use them to cover the top of the container. Overlap the strips on top of each other about half an inch of their width and let a couple of inches of tape protrude from the edges of the container.
- Run a finger along the edge to seal everything well.
- Make sure there are no openings, otherwise the silicone will leak out of the container.
Step 4. Adhere the ends of the tape to the sides of the container
Once you have filled the container with silicone there is a chance that a small amount will seep out from under the tape, but this will prevent it from leaking out and ruining your work area.
Step 5. Place the object (or objects) you want to mold into the container
Place the container (with the open side facing up) on a flat and stable surface and place the objects inside it by pressing them against the adhesive tape, taking care that they do not touch the sides of the container and space them apart. Also make sure that the part with the pattern is facing up and that the back is pressed firmly against the tape.
- This method is best suited for objects that have a flat back.
- If necessary, clean items thoroughly before starting.
Step 6. Dose the required amount of silicone according to the instructions on the package
You will always have to mix compound A and compound B. Some types of silicone are dosed by volume, others by weight. Read the instructions included in the package carefully and stick to the recommended dosages.
- Pour the silicone into the cup provided with the kit. If not included, pour it into a disposable plastic cup.
- You will need enough silicone to cover the surface of your object with a layer of about half a centimeter.
Step 7. Mix the two components until you get a homogeneous color
You can do this using a stick (or similar object) or a plastic fork, spoon, or knife. Keep stirring until you get a uniform color or no more streaks.
Step 8. Pour the silicone into the container
Use the tool you mixed with to help you clean the cup well, so that all of the silicone is used. The surface of your object will need to be covered with a layer of silicone about half a centimeter high. In fact, a silicone mold that is too thin could tear.
Step 9. Let the silicone harden
The time it takes for hardening depends on the brand you are using. Some allow you to use the mold within a few hours, while for others you have to wait until the next day. Consult the instructions included in the kit for more precise information regarding waiting times for hardening. Do not touch or move the mold during this time.
Step 10. Take the silicone out of the mold
Once the silicone has hardened, remove the masking tape from the container and gently pull out the mold you have obtained. You may notice fine silicone burrs around the edges. If you don't like them, remove them using a pair of scissors or a utility knife.
Step 11. Extract the objects from the mold
The items you put inside the container will be stuck inside the silicone. Gently fold back the silicone to let the items out (a bit like you would with the ice cube tray to take out the cubes).
Step 12. Use the mold
Now you can fill the cavities of the mold with resin, modeling paste or even chocolate (if the silicone is for food use). You can unmold objects made using modeling clay when it is still damp. For those made with resin, however, you have to wait for it to dry completely before you can unmold them.
Advice
- Although the objects do not stick to the silicone, it may be a good idea to spray the inside of the mold with a release agent before pouring the resin.
- Molds made using building silicone and liquid soap or corn starch are not suitable for baking or for making confectionery because this silicone is not suitable for food use.
- If you want to make a candy or chocolate mold you will need to purchase a two-part silicone kit and make sure the instructions specify that it is suitable for food use.
- Two-component silicone molds will last longer than those made with building silicone, as the materials used to make them are specific for professional reproduction jobs.
- Silicone molds won't last forever. Over time, in fact, they tend to deteriorate.
- Two-component silicone molds are the most suitable for making resin reproductions.
Warnings
- Avoid touching building silicone with your hands as it can irritate the skin.
- Building silicone can produce noxious fumes, so make sure your work area is well ventilated.
