Cornstarch Based Modeling Clay

Clay Recipes & Tips

Here are some ideas for using cornstarch based modeling clays. These are variously known as cold porcelain clay, Victorian salt clay, and pasta francesa. I like the porcelain designation because cornstarch based modeling clays are pure white and if sealed after drying, they actually resemble fine porcelain.

The pictures on this page are all cornstarch modeling clay jewelry.

Cornstarch modeling clays require cooking to prepare. They air dry; but drying can be accelerated in a warm oven. The shelf life varies from one week to one month depending on the ingredients, storage temperature and humidity.

A few tips for working with cornstarch based modeling clays:

Expect shrinkage of up to 30% as your pieces dry;
You may add powdered or liquid paint (see specific recipe for type of paint to use) either when making the clay or when you are ready to model it, but adding color before storing it reduces the clay's shelf life;
Adding too much paint alters the recipe and could cause the dough to dry out or crack when cured - if you want intense color, reduce one of the liquid ingredients (water if using water-based paint, oil if using oil-based paint);
Projects may also be made with uncolored clay, then painted after curing;
A small amount of hand cream on your palms will help you make smoother forms;
Can be hand modeled, as well as pressed into molds;
Can be used to make molds, for example if you have a large cameo, make your own mold by pressing it into a flattened piece of clay, let dry, then make your own cameos using the mold (note they will be smaller than the original because of the double shrinkage;
Impressions like "Believe" or "Love" can be carved or stamped into the dough while soft;
To make jewelry beads, punch holes with a large sewing needle or skewer while the clay is soft;
To prevent beads from flattening while drying, string them on a stiff wire such as a piece of clothes hangar and suspend across a shoe box;
It takes an average of 2 days for a modeled object to dry at room temperature ;
For quicker results, preheat oven to 350 degrees F. Turn oven off. Place the project on a wire rack in the oven and leave until the oven has cooled off;
Cured objects may be smoothed by rubbing gently with sandpaper, emery board or emery cloth;
When dry, can be antiqued by painting over with black, gold, brown, etc., then burnishing off of the high surfaces with a soft cloth;
Spray cured project with Krylon acrylic sealer or brush on Delta Air-Dry PermEnamel Clear Gloss Glaze for a porcelain look;
Pastel colors will be darker when cured but can be lightened a bit if you seal as above;
Do not use your products for food or beverages [ For explanation, read Polymer Clay Safety Tips, especially the section "Food and Polymer Clay" . The same logic applies. ];
Store clay in a cool, dark place wrapped in plastic or sealed in a Ziploc bag placed in an airtight container.

Cornstarch Based Modeling Clay Recipes

Cornstarch Modeling Clay Recipe #1

Cold Porcelain Clay
courtesy of Fiona Guagliano

You can see some of Fiona's beautiful clay figurines by clicking here.

Her creations are both stunning and whimsical and are certain to inspire new craft ideas in you.

[I read somewhere in a Spanish website that authentic cold porcelain clay contains alabaster powder, but no matter, this looks like porcelain to me.]

1. Combine in a Teflon-coated pot:

1 cup polyvinyl acetate glue such as Elmer's Glue-All
1 cup cornstarch
2 tablespoons Vaseline oil (not jelly) - if unavailable where you live, substitute baby oil or pharmaceutical grade mineral oil
1 tablespoon lemon juice.

2. Cook on low heat stirring constantly for 10 minutes or until dough forms and begins to come away from the sides. If you have a gas stove, you may need to use a heat diffuser under the pot to avoid burning the dough.
3. Remove from heat and allow to cool until you can handle it.
4. Knead into a smooth clay consistency.
5. Store in a cool, dark place as noted in tips above.
6. Tempura powder or acrylic paints may be used for coloring the dough.

Thank you, Fiona, both for the recipe, your craft ideas and for your delightful website!

Cornstarch Modeling Clay Recipe #2

Victorian Salt Clay

[ Gosh, this recipe is so old; I don't even remember where I got it. If anyone knows the source, please let me know so I can give proper credit. ]

Cornstarch modeling clays containing salt are the most porous, so are only suitable for craft projects that have a rough or rustic finish.

1. Mix 2 cups salt and 2/3 cup water in a pan.
2. Mix 1 cup cornstarch and 1/2 cup ice water in a bowl.
3. Stirring constantly, heat salt combination over a low flame for about 4 minutes. Do not boil. If you have a gas stove, you may need to use a heat diffuser under the pot to avoid burning the dough.
4. Remove from heat. Quickly stir in the cornstarch and water. If mixture is too thin, return to low heat and stir constantly until of clay consistency.
5. Store in a cool, dark place at noted in tips above.
6. Tempura powder or acrylic paints may be used for coloring the dough.

Cornstarch Modeling Clay Recipe #3

Pasta Francesa

Variations of this recipe are very popular in Latin America. Many call for 10% formaldehyde (formalin or formol)*, but this is optional.

I believe it is much safer to purchase commercial polymer clays than to make your own. However, if you can purchase formalin* in your area and would like to try making your own polymer clay, read and follow the precautionary information provided by the University of California, Davis.

1. Mix in a dedicated Teflon-coated pot until completely dissolved:

1 cup cornstarch
1/2 cups water.

Add and incorporate

1 cup polyvinyl acetate glue such as Elmer's Glue All
1 1/2 tablespoons glycerin
1 1/2 tablespoons cold cream with lanolin
1 1/2 tablespoons white vinegar or 1/4 teaspoon formalin*

2. Cook on low heat stirring constantly until dough forms and begins to come away from the sides. Take care not to overcook or the dough will harden. If you have a gas stove, you may need to use a heat diffuser under the pot to avoid burning the dough.
3. Remove from heat, cover with a damp cloth and allow to cool until you can handle it.
4. Knead into a smooth clay consistency.
5. Store in a cool, dark place at noted in tips above.
6. Oil paints may be used for coloring the dough before curing; oil or acrylics may be used to paint after curing.

Once you have made the clay, your personal craft ideas can take free reign. The types of crafts that can be made are mind boggling!

Please share your craft ideas on the use of this clay with us.

*Formalin is a solution containing formaldehyde and is very toxic. If you are planning to use it in your recipe, make sure you read and follow the precautionary information provided by the University of California, Davis.

Failure to do so can lead to serious health risks.

It is much safer to use commercially made clays. (See Letter below.)

Be sure to read my other articles about Home Cured Modeling Clays

While reading your recipes for modeling clay I stumbled across recipe #3 and noticed that one of the (optional) ingredients were formalin.

Formalin is another less known name for formaldehyde and is very, very toxic.

I would really like to see this recipe removed from your site before people use it and end up sick.

Michael

Thank you for your opinion, but I respectfully disagree.

I believe my article on Cornstarch Based Modeling Clay Recipes does a public service.

I explain that recipe #3 for pasta Francesa is very popular in Latin American countries.

I have lived in a third world country where one can walk into a neighborhood pharmacy and buy formalin (formaldehyde) over the counter.

The reality is that people in these countries are buying formaldehyde and making polymer clay in their homes and studios. If they find the recipe on The Artful Crafter, they will at least have access to information on its dangers and the safety precautions they should employ if they decided to use it anyway.

My article identifies formalin as formaldehyde and labels it as an optional ingredient several times.

The Artful Crafter has a wide reach, so that if anyone anywhere in the world is searching the Internet for "clay recipes" or "pasta Francesa", I hope they will find my article and have the benefit of reading the warning paragraph.

"I believe it is much safer to purchase commercial polymer clays than to make your own. However, if you can purchase formalin in your area and would like to try making your own polymer clay, please read and follow the precautionary information provided by the University of California, Davis."

Eileen

Thanks a lot! I have asked for recipes of pasta Francesa and no one gave one with the exact proportions.

I live in Uruguay and the persons who prepare it don't use formalin but vinegar. I guess it must have a similar formula and it isn't toxic.

I will try and make the substitution because I will be able to use whatever pan from my kitchen.

Thanks a lot again. Your page is just perfect for crafts lovers.

Raquel

Thank you so much for writing, Raquel, and for suggesting the substitution of vinegar for the controversial formalin (formaldehyde). Your letter (from Uruguay) really confirms my belief that this website provides a valuable service in educating crafters about the risks and precautions they should be aware of with certain materials.

I am so glad you are finding the site useful!

Eileen

P.S. After much experimentation, I worked out the pasta Francesa recipe with vinegar. This option has been added to the recipe above.

Hi!

I love your site, especially the clay section. I've been reading your clay recipes and I would definitely try one of them.

I also saw where you got the Victorian Salt Clay recipe.

Cheers!

Amber

Well some things never change.

The ingredients at Pioneer Thinking are exactly the same as the recipe I used when I was teaching elementary school twenty-five years ago and have kept on an index card in my recipe box all these years.

When I was a kid (some fifty years ago), we simply called it salt clay.

My two sisters and I mixed salt clay in the kitchen without even measuring. We stored bags of it in the refrigerator.

Invariably, one of our three brothers would go scrounging in the fridge for a snack and take a bite of the clay dough.

I have no idea what they thought it was going to taste like or why the red clay might taste better than the green they ate last week; but boys will be boys.

As for this classic recipe - hey, if it ain't broke, don't fix it.

I'm so glad you're enjoying the site ;-)

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