Introduction: Cast Your Own Concrete Charm

About: Welcome! Pleased to meet you, I am Barb; a Maker. I have been making things AND explaining how to make things for as long as I can remember. I was all about DIY before it was a popular term. I absolutely love …

I love to see creativity at it's best... Making objects out of unexpected materials is one of those. Since I am a concrete-o-holic I just had to make a charm or pendant from my favourite medium.

It's really quite an easy casting project, a good start before you also become a concrete-o-holic! (and cast more like these) No special material needed...

Step 1: What You Need to Make the Mold:

Don't you hate when you have to buy fancy expensive products to make things?! I will be making my own reusable mold for this out of easy to find household items so it is inexpensive!

The supplies:

  • 100% Silicone Caulking (not acrylic) any colour will work
  • Caulking Gun
  • Corn Starch
  • Gloves
  • Bowl (that will get messed up)
  • A Charm from which to take the mold (can be what ever you like, plastic, metal works best)

You can use anything that you think is interesting. If you are concerned about the mold material sticking then you can give it a thin coating of vaseline.

Step 2: To Make the Mix

Mixing this material is very much like making a bread dough.

  • I put a generous amount of corn starch in a bowl to cover the bottom well.
  • Put the silicone in the caulking gun after cutting tip and poking a hole in tube
  • Squeeze enough that feels like it would cover your object in one pile
  • Carefully work the corn starch onto it so as to keep it from sticking to your fingers.
  • Turn it and keep it covered in starch to incorporate it without sticking to bowl or fingers
  • Start to knead it until it no longer sticks
  • Make a ball that has a smooth consistency.

Step 3: Wrapping Your Master Object

Now that you have a good molding compound you should work pretty quick. (it only has a few minutes of working time)

Flatten the dough to be able to wrap the object. Since my object was hollow I made sure NOT to squeeze the dough too firmly as I did not want it going deep into the shape.

Fold over the sides and envelope the whole thing.

It can be set in as little as 15 minutes. Once it is set it will not be malleable any more. Once rubbery it is set.

Step 4: Open Your Mold

Since this is a one-part mold; an unconventional way to make an entire mold it will need to be cut open.

Take a sharp exacto knife and cut open at the mid point.

Since I wanted it to be closed at the bottom and it is quite flexible I will keep it half attached.

Even though I did not use any mold release the object came out easily. The only material that I have had stick is glass. The cornstarch seems to make it not completely adhere to most materials.

Step 5: What You Need to Cast It:

Now that you have your mold you will need:

  • Rapidset Cementall
  • Container to mix in & mixing spoon/stick
  • Water
  • gloves/dust mask
  • wire and pliers
  • elastic bands

Since you will probably want some way to attach the charm you will need to make a loop of some shape/size. Use round pliers to make a round loop and have extra bent wire that will be imbedded into to concrete securely and to not pull out.

Step 6: Pouring You Casting:

Mix the concrete mix with water. This is not ordinary mix and does use less water but becomes crazy-strong. It should have some flow to it but not as thin as cream.

Prepare your mold to be able to see where the middle top is. Cut away any excess easily with an xacto knife

Hold the top of the mold open and pour enough in until it just oozes out. To secure the openings elastic bands work well. Tap a bit to dislodge any bubbles and get the mix to fill in the small details.

Slide a loop into the mold making sure it is centred.

This mix is unmoldable in 1 hour!

Open it up and be amazed...

Step 7: Finish It to Your Liking:

This may be kept quite simple or fussed over more. Concrete should be kept pretty simple but make sure to smooth some of the rough spots so as not to catch on clothing.

Emery cloth will work off the rough edges and it can be washed up.

As usual; I always like a bit of bling... Silver leafing is just too easy. Follow instructions on the package, but keep it to a minimum...

Add it to a chain or leather cord, or make it into an indestructable keychain!

This mold will last quite well for numerous casts and remains nicely flexible.

For more concrete casting and tricks visit my site:

Step 8:

Pocket-Sized Contest

Participated in the
Pocket-Sized Contest

Trash to Treasure

Participated in the
Trash to Treasure