Epoxy Clay + Silicone Rubber + Epoxy Resin = Cool DIY toy!
Make your own geometric shaped toy by breaking down your object into non complex geometric parts. This procedure is optimized so that the piece is easily cast and reproduced with the use of a silicone mold and epoxy resin.
I picked this step by step project because of its accessibility and high end result possibilities. Hope this works as kick starter for a lot of people out there that have the drive and want to make their own toys but didn't know where to get started.
Step 1: Things You Will Need:
- Two part epoxy clay;
- Iron wire;
- Isopropyl alcohol;
- PS (polystyrene) sheet;
- Silicone + catalyst;
- Epoxy resin;
- Rubber gloves;
- Containers for mixing substances;
- Glue stick;
- Glue gun;
- Utility knife;
- Spray paint;
- Masking tape;
- Permanent marker.
Step 2: PART 01 | Making a Model | Sketch.
Sketch out the basic structure of the toy you want to make, as close to 1:1 scale as possible. You'll use it as reference throughout the modeling process.
Step 3: PART 01 | Making a Model | Wire Frame.
Build wire frame like structure using thin iron wire and pliers. This structure will hold the object's basic volumes and shape.
Step 4: PART 01 | Making a Model | Epoxy Clay.
Mix the epoxy clay (50/50) into an even light grey. Apply a first layer of the clay on top of your structure. Constantly check the sketch you made to see where you should put more clay and how the proportions work out looking from different angles. Don't over apply it at this point, all you need is a basic epoxy layer that will work as foundation for other fine tuning layers of clay. They will be applied after a couple of hours when the clay is close to completely dry.
When working on the second layer you should start using the isopropyl alcohol to make the clay work in ways similar to natural clay. Get your fingers wet with alcohol as you apply the new layer. Try to get closer to your final look, leaving smaller adjustments for later.
In a simple small piece like Mario's mushroom, you'll probably have your final object after the third or fourth layer of clay. Don't try to rush things and get your hands on it again before the two hour basic drying time is done, the point here is to reach the piece you have in mind a step at a time, "slowly" modeling the layers of clay into the shape you want.
I usually model the geometric basic parts separately. For this one, I had a cylinder for the main body, a round shape to put on top and a couple of small cylinders for the eyes. I wait until each part is dry and hard before putting them together.
Step 5: PART 01 | Making a Model | Sandpaper Smoothing.
You might notice that there are fingerprints and irregular tiny bumps all over the model still… It doesn't look all that polished. In order to even out the surface, use sandpaper to correct minor imperfections. In some models you might even want a small drill type of tool to get the forms you imagined, the epoxy clay is easily carved even though it feels hard as rock.
Following these steps you can have quite a share of control over the making of the model. It's just a matter of adding and removing material bits at a time to work your way to the final volumetric result.
CAUTION: You have to keep in mind that the shapes you are modeling are going to be cast and unmolded at some point, so they need to be designed in a way they don't get stuck in the mold or what have you.
Step 6: PART 02 | Making the Mold.
Build a container a couple of times bigger than your model. For this you'll use a PS (polystyrene) sheet and a glue gun. Cut a strip of PS and roll it into a cup like form, glue it to another piece of PS (a square or a rectangle to fit the cup with room around it). Make sure you have plenty of glue along the edges of the cup so that the silicone mix won't leak out.
Tape (or fix it some other way, I used a few books) the container and the base onto a flat and leveled surface. Make sure it is really sturdy and flat. Use a glue stick to glue the model to the bottom of the container. Make sure it's well centered so that the silicone spreads evenly around it.
Mix the silicone with the catalyst and use a brush to apply the liquid to the surface of the model, make sure you cover any parts that might be harder for the silicone to reach.
Slowly pour the silicone in the container, fill it from bottom up evenly, give extra attention to area right around the model so that the silicone fills in properly.
Wait for about 6 hours before unmolding.
Step 7: PART 03 | Making a Copy of Your Model Out of Resin.
Mix the epoxy resin components. 50/50 mix ratio. Don't take too long because the reaction is pretty quick and the substance hardens considerably fast.
Pour the resin in the mold, making sure it touches all of the surface inside. As you first pour the resin, turn the mold in different directions so that the resin spreads inside it (like people do when making chocolate easter eggs). Cover tiny holes and spaces where air might come in before other parts. Also make sure that any bubbles come out of the liquid when you fill up.
Wait a few minutes and the copy is done!
Step 8: PART 04 | Painting.
Cover all the parts you don't want painted red (or any color you want to use in the top of the mushroom for that matter) using masking tape and stickers with the shapes you want. In the mushroom's case I used round stickers to make the dots on its top.
Use the red spray, don't point the can to the object from up close, do it from a distance in thin layers, wait a while in between each coating. You don't want the paint to over accumulate or drip... Uncover the masked parts.
Use a black permanent marker to paint the eyes and there you have it! Mushroom clone #1!