Cold porcelain and how to use it for modelling gas monkey cast

You can also find a range of recipes for cold porcelain on the Cold Porcelain Tutorials Site as well linked from The Glass Attic. Cynthia Howe Miniatures has a recipe and instructions for making cold porcelain as well. How Long Does Cold Porcelain Last?

Cold porcelain paste is often combined with preservatives to try to extend its working shelf life (and make sure it doesn’t mold), which is at least 1 week without preservatives under normal household temperatures if the material is properly wrapped. Preservatives in recipes include witch hazel, lemon juice, citric acid powder, and oil of cloves. Sodium Benzoate is used in some recipes. Some earlier recipes include formalin/formaldehyde as a preservative, which should be avoided as it is hazardous to health. Check commercial porcelain clay mixes for the preservative ingredients before purchasing!

Cold porcelain should be wrapped in cling film and stored in an air tight plastic bag/container in a cool area after mixing. I should not be stored in the fridge or freezer, as this may affect the PVA glue. Some recipes which contain glycerine will store in the freezer for reportedly up to 3 years. This may be affected by the brand of PVA glue you use, so experiment with freezing your favorite recipe.

Remove only small amounts from your storage container as needed and work color into the amount you have removed. Excess of any color mixture can be wrapped in cling film and stored. Some coloring agents can reduce the shelf life of cold porcelain by drying it out faster, so avoid mixing in color (including white) until you are ready to work with your cold porcelain mix. Coloring Cold Porcelain

When it dries, cold porcelain is a semi-transparent material, so white acrylic (tube acrylic) or a white dry paint pigment (titanium white) should always be added to any clay you want to be more opaque. The mixed clay can be colored with paste or powder food colorings, watercolor paints, acrylic paints, powdered paint pigments or pastels/chalk dust. The use of oil paints as tints is possible, but not advisable for material which will be handled without gloves for modeling.

Cold porcelain resembles sugar pastes and fondants in its working characteristics. It is fairly soft and does not hold sharp detail although it can be shaped into very thin sections (flower petals) with some transparency. It ‘frills’ and waves easily along fine edges so for larger flower miniatures it works well. There are some miniaturists who use this material for small scale flower work (Diane Gould (Harfield) is probably the best known This is not a material which can be layered for ‘caning’ like polymer clay. Most items made from cold porcelain are fairly small as cracking becomes a problem with larger models. The material is easy to layer and assemble using pva glue.

When working with cold porcelain you will want to have on hand standard modeling tools, as well as texturing tools, a container of cornstarch/cornflower to dust your tools to prevent sticking, and some hand cream or baby oil, to coat your hands or tools to prevent sticking. To blend successive layers of cold porcelain or ‘join’ parts you may need to wet the main section with a bit of water or sand it slightly to give it tooth (if it has dried) before you can add on the additional layers.

All forms of cold porcelain clay will shrink, usually between 15 and 20 % as they dry. Test your mixture to determine how much shrinkage you can expect before you work on larger pieces or you may run into cracking as the clay dries faster on the outside. Storing and Displaying Cold Porcelain Models

As cold porcelain is based on starch, it may be attractive to insects and should be kept away from any other art pieces which could suffer insect damage. The preservatives used to keep the clay from going moldy in its working state will not protect it against insect infestations.

Take care how and where you store or display cold porcelain items. As cold porcelain will absorb slight amounts of moisture and is not entirely waterproof, it may need to be protected from moisture or humidity once thoroughly dry using some type of waterproof varnish (acrylic varnish). A thorough coating of acrylic paint over the surface may also act as a protectant. Cold porcelain models should not be subjected to humid or wet environments. If possible, display cold porcelain items in protective glass or acrylic cases, which include a small drying agent package of silica gel to absorb any humidity.