How To Copy A Starfish: A Two-Part Mold

Posted on 13 Apr 12:32

Need a little splash of creativity?

Fishing for something new to do?

Why not take a memory from a past vacation and put your own creative spin on it? Seashells, sand dollars or starfish are wonderful objects that you can copy and design however you like using Mold Making Material.

Objects with a flat side or base can be molded in one sitting with the One-Part Mold Method. Objects like the starfish don’t have a flat portion anywhere so they require the Two-Part Mold Method that we'll explain here. It's the best way to capture the texture of the whole object.

Let's "sea" if you can do it.

 

First, measure and cut a cardboard box big enough to fit the starfish. Line the inside of the box with packing tape so that it's waterproof and will easily release the mold.

How To Copy A Starfish: measure and cut a cardboard box big enough to fit the starfish

Grab some Plasticine and spread it out inside the box so that the whole floor is covered.

How To Copy A Starfish: Grab some Plasticine and spread it out inside the box

Place your starfish into the Plasticine so that it is halfway covered. The starfish is delicate so be careful not to damage it.

How To Copy A Starfish: Place your starfish into the Plasticine

Now it's time to bring on the Mold Making Material. Carefully measure out equal amounts of Part A and Part B by volume, not weight. 

How To Copy A Starfish: bring on the Mold Making Material

Combine the 2 parts and mix until the color is a consistent blue.

How To Copy A Starfish: Combine the 2 parts and mix until the color is a consistent blue

Pour the Mold Making Material mixture over the entire half of your object that is exposed in the Plasticine.

How To Copy A Starfish: Pour the Mold Making Material mixture over the entire half of your object

Now wait approximately 3 to 4 hours for the Mold Making Material to cure. Once that time has passed, cut and remove the Plasticine and mold from the box. Try not to damage the box as you will be using it again to pour the second half.

How To Copy A Starfish: Try not to damage the box as you will be using it again to pour the second half

Remove all of the Plasticine, cleaning off any little bits that may be clinging to the object or mold.

How To Copy A Starfish: Remove all of the Plasticine

Now it is time to make the second half of the mold. Flip over the mold and place it back into the cardboard frame. The starfish should be on top. 

In order to fill the completed mold we need a pouring spout (FUN FACT: technically this is called a sprue). Take a straw or a small amount of the Plasticine and place it at the tip of one of the legs, against the box.


This pouring spout will provide the opening for you to pour in the substance that you intend to use to make your duplicate objects.

How To Copy A Starfish: pouring spout will provide the opening for you to pour in the substance

Once again, measure, mix and pour the Mold Making Material over the rest of the starfish and wait another 3 to 4 hours for the mixture to cure.

How To Copy A Starfish: Mold Making Material over the rest of the starfish

Remove the mold from the box as you are now ready to remove the starfish from the mold.

How To Copy A Starfish: Remove the mold from the box

After removing the Plasticine spout, carefully cut an opening big enough to remove the starfish. In this case, we cut from the hole, down the top leg of the starfish, and across to the next leg.  This cut was done symmetrically down both sides. 

How To Copy A Starfish: cut was done symmetrically down both sides

From there, only two legs were left completely inside the mold, and we were able to pry the mold open and remove the object.  Cleaning out the starfish mold is important as the organic object had debris that came loose in the mold.

How To Copy A Starfish: pry the mold open and remove the object

Your Two-Part Mold is complete and you can now make exact replicas of your object.

You can use many different substances to fill the mold, such as cement, plaster, polyurethane, soap, clay, polymer clay, play dough and wax, but we recommend ArtResin epoxy resin in combination with our line of ResinTints. 

💡 TIP: You can also use Mold Making Material for food safe molds to create personalized shapes out of chocolate, candy, ice, butter and more!  Just remember, molds made for use with food should ONLY be used for food.  For more information, see our blog Make Your Own Food Safe Silicone Molds.

How To Copy A Starfish: ArtResin in combination with our line of ResinTints

Just like Mold Making Material, ArtResin is a simple 1 to 1 ratio of resin and hardener. Measure out equal parts of both solutions and mix thoroughly for 3 minutes. You’ll have approximately 45 minutes of working time with the resin mixture before it will begin to set.

Just like Mold Making Material, ArtResin is a simple 1 to 1 ratio

Grab any color of ResinTint and pour a few drops into the ArtResin. Then just mix 'er up.

How To Copy A Starfish: Grab any color of ResinTint and pour a few drops into the ArtResin

Because you had to cut the mold open, you now need to tape the mold closed using Tuck Tape or packing tape.

How To Copy A Starfish: cut the mold open, you now need to tape the mold closed using Tuck Tape

Make sure it is securely sealed and slowly pour ArtResin into the mold through the pouring hole. If the hole is small, you may want to use an eye dropper.

How To Copy A Starfish: ArtResin into the mold through the pouring hole

ArtResin is hard to the touch after 24 hours but a full, hardened cure will take 72. Once your starfish has cured, remove it from the mold and admire your handiwork!

How To Copy A Starfish: ArtResin is hard to the touch after 24 hours but a full

From there, have fun and create as many replicas as your heart desires.

...Do you copy? ;)