Showing posts with label molding and casting. Show all posts
Showing posts with label molding and casting. Show all posts

Backdating Mold Making and Casting

The techniques of mold making and casting are nothing new. In fact, they emerged way back in the Neolithic times and gradually developed as the key for making most of the objects we use and enjoy today.

Mold making and casting procedures are used to make most of the things we use – from household goods and decorative items to industrial equipment and structural components. These techniques are especially popular in the world of art and design and are patronized by artists of various genres. They are commonly used for new artworks, art reproductions, sculpture making, ceramic works, garden statuary, candle making, props, masks and the like. The same are also applied for architectural restoration works, prototype tooling, taxidermy, fossil preservation, etc.



Not to mention the beautiful art of life casting. Indeed, life casts have emerged as a magnificent mode of creating a three-dimensional reproduction of the live human body. The regular techniques of making molds and casts are used with appropriate skin-safe materials to make body molds and life casts of the face, hands, feet, belly, torso or even the entire body. These are extremely popular for infants, friends, families, pregnant mothers and more. The same is also used for medical prosthetics, special effects, animatronics, etc.


The synthetic materials like polyurethane resin, latex rubber and silicone rubber may be new additions to the fold, but mold making and casting themselves are not contemporary techniques by a long shot. In fact, they date back to the prehistoric times when settlements were being established and agriculture came into being. The primitives slowly developed these processes to fabricate tools, equipment, jewelry and religious artifacts What’s more, the oldest surviving casting of a copper frog dates back to 3200 BC!

With the passage of time, these techniques were applied for making and reproducing artworks, especially sculptures. The introduction of hollow wax casting was the precursor to the highly prized Greek statues and Roman copies made later.

Clay and plaster continued to be the popular medium of making molds and casts down the ages. Gradually, art schools started teaching mold making and casting and used wood or terracotta also to make the molds. This led to the creation of iconic artworks that remain illustrious till date. Simultaneously, they were used for making pottery and ceramics as well.

These age-old processes finally made their way from the homes of royals, aristocrats and art aficionados to the foundries of today. The advent of industrialization witnessed a quick adoption for the mass production of regular objects in a range of styles. Injection molding was introduced in industries and new materials like plastics and polymers also came into being. Everyday items became inexpensive due to lower costs of production.



These techniques were progressively incorporated into the making of complicated automotive parts, equipment, machinery and even structures.

Indeed, from the simple molds and casts of ancient times to two part molds and cold casting for artworks to highly technical and complex processes in industries - mold making and casting have surely come a long way!

How To Use Silicone Rubber

Silicone rubber is a material of choice for making molds of figurines, giftware and robotic figures to even prototype tooling, prosthetic pieces and special effects. A wide variety of silicone rubbers are available in the market ranging from the regular silicone formulations to skin safe, food safe and skin-like translucent options.



Not only does silicone perfectly capture the surface details of a model, but the rubber is very simple to use too. Following is a look at what goes into making a simple silicone mold:

•    Silicone rubber is a two-component material with the base and catalyst usually mixed in the ratio of 10:1 by weight. You need to stir and shake them properly before weighing the appropriate amounts in separate containers. Place the base material in the mixing container and roll it around to coat the sides as well.

silicone RTV rubbers

•    Pour the catalyst into the container and mix them thoroughly making sure that any material is not left unblended on the sides or bottom. You should not use a mixer machine or even mix too vigorously as this will introduce air bubbles into the silicone rubber.

•    Despite the most careful mixing, some air is bound to get entrapped in the mix and will form unsightly bubbles on the mold. Degassing in a vacuum chamber will release the air and make the rubber bubble-free.

•    Once vacuumed, slowly pour the mixture in a thin stream from a corner of the mold box till a thick and even layer forms all over the model.



Quality Silicone Mold Rubbers


•    Keep in mind that though the work life of silicone varies from one brand to another, it is usually under an hour. Even the pot life is limited to a couple of hours at best.

•    As silicone rubber does not stick to anything but itself, it will get demolded easily. Yet, some mold makers prefer to coat a thin layer of release agent to allow the mold to slide off without any effort. Sealing the model and mold box is essential as the rubber may get absorbed into them.

•    The rubber mold requires 16 to 24 hours to air cure. Demold only when the mold feels rigid and is no longer tacky. Allow it to remain at least another day before proceeding to casting. Full cure may take almost a week.

•    The cured silicone rubber mold is usually blue in color. It will reproduce the exact detail, have a smooth finish and is ready for casting. You can cast polyurethane resin, epoxy resin, polyester resin, polyurethane rubber and many other materials in the silicone mold simply by pouring the material into the mold. Demolding the cast is also easy as silicone rubber will not stick to anything.

mold making silicone rubber


In sum, silicone rubbers are a great option for making molds of various objects.

Be Familiar With The Types Of Casting Resins

The desire of man to do something innovative as well as eye-catching is the main reason behind the invention. It is not the story of the era. From centuries ago, people have developed several things to make their life comfortable and the process is continuing still today.



Molding and casting are the processes with which one can let his or her imagination run free. Resin casting is one among them. It is a method of plastic casting where a mold is generally filled with synthetic resin that later hardens.

Casting resin falls into three classes epoxy, polyester and polyurethane. Polyester resin is used for its mechanical properties. It is a contact product that requires no pressure to cure as well as can be cured from a fluid or solid state. The two varieties of polyurethane resins are opaque and water clear resin. Epoxy resin is more expansive than other types. It might take several hours to several days to completely cure.

polyurethanes resin casting

Each of the products comes with several advantages. Based on your requirement, you need to decide which one will be the right choice for you. EnvironMolds, LLC is a reputable shop in the field of molding and casting materials. They provide high-quality products at reasonable prices. If you want to get any of their products or have any queries, then feel free to call them at 1-866-278-6653.