Wednesday, August 14, 2013

CP Tips from Marisol

Marisol rosemary and their works
Marisol Romero

What is Cold Porcelain?  Cold Porcelain (CP) is a modeling compound that is composed of white glue and cornstarch.  The recipe for cold porcelain is quite simple and it can be made or home or purchased commercially.   CP is a material that can be modeled in small volumes and large. Its characteristics are softness, whiteness and elasticity. CP is known throughout the world, in every region or country, by many different names.  Besides Cold Porcelain, it is known as Porcelana Fria, Masa Flexible, Biscuit, and Pasta di Mais among others.

See this page for recipes and how to make Cold Porcelain video. If you make your own dough, keep in mind that, to be of good quality, the ingredients you use should also be good quality.

Marisol Romero is a cold porcelain artist from Argentina, where this medium is very popular. On her website she shares some of her cold porcelain tips.  Below are some of her tips translated to English as best as we can!


The CP dough does not require baking and dries at room temperature. Another feature is that, as it dries, it loses 15% to 20% of the initial volume. For this reason it is good to consider the proportions of what you want to model.  If you doing all the parts together, you should have no problem.  The issue of proportions arises when you dry the parts separately and then assemble them with fresh dough. Always add 20% to everything you do.  If you are modeling in a large size, there are times that you must add up to 30%.

The dough quality often depends on the glue you are using.  The glue is an essential ingredient and important in the dough.  It has to be of very good quality to avoid the dreaded cracks that may appear when the piece begins to dry  Test different brands of vinyl glue.  The elasticity of the dough depends a lot on the glue. The only way to know if it is good is testing and testing again. The most expensive or best brand is not always the one that will help us make good cold porcelain.

After preparing, you must knead dough until it's cool, or at least until it stops sweating.

Uncured CP can be tinted with acrylics, tempera, oils and vegetable dyes. Also, once dry, the piece is paintable and different effects may be achieved with pastel chalks and other mediums.

There are a variety of recipes for making cold porcelain.  These recipes often call for Glycerin, stearin and Sodium Benzoate .   These ingredients can be found in bakery supplies and in craft shops.

Benzoate is a preservative that can be replaced with 1 teaspoon of white vinegar or alcohol.   Glycerin is edible and you can get in bakeries.  Vaseline is commonly found in drug stores.  Stearin is one of the ingredients that may be more difficult to find but CP dough may be made without it.

In some countries they use formaldehyde as a preservative, but as it is toxic and may effect the eyes, I do not recommend using.  

Many people are using vinegar as a preservative.  However, in all the years I've been making my own cold porcelain, I've never had fungus problems.

Both the homemade and purchased CP must have the same useful lifetime.  It should not crack or produce fungi.

You have to remember that the results you get when making CP will also vary according to the climate where you live. In dry climates some figures work well because they dry fast. In humid climates, or days of high humidity, the CP can lose it's shape as it stands.

Keep in mind that if cracks appear when drying it is often the poor quality of the ingredients.  Cracks can also occur from bad modeling.

Here is a very simple technique to test if the consistency of your CP dough is ideal.  Create a tower of doug of about 20 cm.  If the tower is leaning or arching immediately, it is because it does not have the best consistency.  You have to cook it more or leave it to aerate if it is commercial produced.

CP hardens because the water evaporates. When you have some dough that is not flexible and is difficult to knead, the dough can be recovered.  How? Cut it into pieces and dip them in a bowl with hot water. Leave it a few minutes and then fold and knead again to integrate the pieces and return to a homogeneous mass.

With this method you return moisture to the dough.  If the dough is still too hard, unfortunately it must be thrown out.

To store the CP dough so that this does not happen, wrap the dough in plastic wrap and then place it in a jar or airtight pot. This flask must not be stored in a place where it will received sun or this will make the dough lose moisture.

In some cases the CP dough may be very moist.  What you have to do is take it out of the bag, let it aerate a little and also knead a few minutes until you notice that it has the correct consistency.


1 comment:

  1. thank you so much for this tutorial, I think I can make it without anyproblems, you explained it so well.

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