Eliminating Air Bubbles in Molds and Casts

There are different mold making and casting equipment that can be used to make bubble-free molds and casts. The suitability of a given equipment depends on the nature of the material and other factors.

One of the most taxing things when making a mold or cast is dealing with the air bubbles. Some air is bound to get trapped into the material no matter how carefully the artist mixes and pours the material. Once set, this shows up as unsightly warts on the surface of the mold/cast and makes it mostly unusable.

Fortunately, there are various tricks and even mechanical equipment for eliminating these pesky air bubbles. While pouring the material in a thin and steady stream from a corner and pricking the bubbles with a pin can help to some extent, it is always better to use an apparatus like vibrating table, pressure pot or a vacuum pump with vacuum chamber.

This brings us to the question – which of these equipment is the most effective in getting rid of the trapped air in the mold making or casting materials?

Well, there is no single-point solution as such.

A vibrating table uses the simple technique of pulsating the material to shake out the bubbles. This will reduce the bubbles but cannot deair the material completely. Careful pouring will reduce the propensity of bubbles for sure.

On the other hand, a pressure pot is best suitable for materials that will cure to a rigid form. Like resins for example. It is better to avoid pressure casting soft rubbers as the air bubbles are bound to return once the mold or cast is exposed to normal air pressure. A rubber mold or cast is even likely to collapse in the areas where air remains trapped under the surface.

A vacuum chamber with pump is best suited for removing air from the rubber materials. Artists usually leave the rubber mold or cast to cure in the vacuum inside the chamber and the air will not return later!

All mold making and casting materials and equipment can be easily sourced from the EnvironMolds website, https://www.artmolds.com.

Preparing for Making a Life Casting

There’s a lot that goes into making a life casting. The procedures and materials may vary, but the artist will always need to prepare his studio and pay particular attention to the model’s well-being.

There are many different ways of making a body mold for life casting – some artists use alginate, some prefer skin-safe silicone rubber, while some simply use plaster bandages to capture the shape and size of the abdomen or torso. Even the life cast can be made in plaster or even with resin for cold casting to replicate the look of stone or metal.

It goes without saying that every life cast is a beautiful work of art and it should be appropriately finished with a brass name plate. This name plate will announce the name of the artwork and the artist along with other details like date of creation.

When starting with the life casting, the artist needs to prepare the place and the model for what lies ahead. It is better to protect the floor with plastic sheets or other covering. Keep hand towels handy. All the required materials and supplies should be kept ready to avoid undue delay while making the body mold. The studio should not be too cold or too warm either. There should be bathing facilities so that the model can wash off the residue once the mold is removed.

In a similar vein, the artist should brief the model about what lies ahead. Discuss the pose and practice it beforehand to ensure proper comfort. Props and supports can be provided if needed. Emphasize the need to stay calm and stationary while the work is in progress. Explain the process so that the model is aware of what will happen.

Finally, the artist should work carefully and without taking too much time over the process.

Life casting artists can procure all the required materials, tools and supplies – like alginate, plaster of Paris bandages, mixers, spatulas, rasps and even name plates engraved – from the EnvironMolds website, Artmolds.com. They also provide instructional materials, workshops and personal guidance, as needed.