coastal decor and crafts

4/30/12

How to Cast Plaster Starfish

Last week I posted about How to Make a Utherane Rubber Mold. Now I'm going to show you how to cast plaster starfish with the mold!

cast plaster starfish
The outcome, very life like. Don't you think?


how to cast plaster starfish with rubber mold
You can use plaster of paris, but I wanted to make my plaster starfish virtually unbreakable, so I went for the reinforced (with fiberglass) stuff, called Hydrocal Casting Plaster. I paid $9 for a bucket at a local art supply store. You can buy it online at places such as Blick Art Materials.

how to cast plaster
Before you prepare the mixture, coat the mold with the mold release spray used for making the mold. Important! To cast one plaster starfish you'll need about three teaspoons of powder. Slowly add water and stir until plaster is thick and even but thin enough to pour. I used a sauce dish!

fill mold with plaster
Wet plaster has a very short working time, only a few minutes.

rubber mold filled with plaster
Shake the mold gently and tap it to bring up air bubbles. Fill in more plaster if needed, shake and tap again. Then let dry for a couple of hours. Also, make sure to clean dish and spoon immediately after casting. If you are planning to Hang Starfish you could insert a wire or twine. when dry, take out the starfish by carefully bending the mold.

plaster starfish
I did smooth out the edges a bit on the backside of the starfish with fine sandpaper.

cast plaster starfish
Now I look forward to grow my cast plaster starfish collection, decorate and craft with them. Here are a few ideas I like: Hang Starfish, Creative Displays and maybe I'll make a Starfish Wreath too. And of course you could paint them in any color you wish!

You might also enjoy these faux starfish crafts:
Salt Dough Starfish
Felt Starfish
Shabby Fabric Starfish

9 comments:

beachcomber said...

very clever! it turned out really well. might have to try it.
x

Flotsam Friends said...

I love it too Maya. Very cool. It appeals to us Australian girls!! Pxxx

Flotsam Friends said...
This comment has been removed by the author.
Shorely Chic said...

This is SO great!! Off to share :)

saltwaterliving said...

what a clever idea!! I have to try this!!

~Lavender Dreamer~ said...

They really come out great and realistic! Great project!

Petaurus said...

Great for the real starfish :) Well done!

Della said...

Great job Maya! These are cool!

iheartsunnydays said...

I am totally going to try this! Thanks Maya - I'm thinking a starfish mirror :)