EnvironMolds offers a great variety of mold making systems - one just perfect for your application. Whether you need a skin safe mold material such as alginate or skin safe silicone such as LifeRite we have it for you and everything in between. You should also view our mold making kits. We have the greatest selection of life casting and molding and casting kits anywhere in one place. Most of our kits are beginner oriented resulting in high quality professional results, even for first-timers. The advantage of our casting kits for the beginner is that each kit contains all the material needed for the finished project. Once you have completed the kit you will know what raw materials to buy to complete another casting.
It is all here release agents, silicone rubber, polyurethane rubber, plaster bandages, liquid latex, clay and waxes, ceramic supplies, alginates and moulage, and yes, even prop food items added to the product mix made from the mold making and casting materials available from the EnvironMolds website.
Mold Making Materials Introduction
Welcome! You are in great company for mold making and molding materials whose history of mold making by man goes as far back as 300 BC during the Bronze age where stone molds have been recovered which were used to cast bronze spear tips. A mold can be as primitive as a dinosaur track where the mud of the footprint has hardened over time in rock to form the matrix. It could be as complicated a multi-part aluminum injection mold used in the manufacture of plastic parts.
The type of mold that one makes is often depend on the type of casting material that will be used to replicate the original. Since this site offers mold making materials that can be readily used at home or in a small studio we will skip the explanation on molds which are required for furnaces to prepare the casting materials... But still it will be helpful to the types of present day molds that are utilized to reproduce castings. To begin with a mold is a basic shape or matrix that can be filled with a pliable material or liquid that when cured takes the shape of the original that the mold was made to copy.
Mold Making Material Types
There are number of types of molds to name a few: blow, injection, matrix, extrusion, rotational, spin and transfer. The majority of which require specialized equipment to complete the process. Here we will be concerned with the types of mold constructions which can be created by you. These include blanket molds, box molds, two-part or complex molds and injection molds.
Finally, an explanation is in order for the types of mold making materials by which molds are constructed. Most mold making materials are utilized are made from natural or manmade rubber because of their flexibility and the ability to reproduce extraordinary detail. But some molds are made with more rigid materials such as gypsum plasters. The most common mold rubbers are natural latex, polyurethane, epoxy and silicone. These groups also breakdown into category types. For example, there are two types of natural latex, one used for mold making while other is used for casting. Silicone has two distinct families, a condensation cure and an addition cure. One is best suited for a certain project over the other. So you need to become familiar with which materials will provide the best results.
Not to be concerned, because throughout this website every material category page has an explanation of the best way to use it in your mold making construction.
Most Common Mold types
This is by far the easiest type of mold. It is often use to reproduce plaques and models in which one side is not covered by mold material. In this process, the original is fixed to a base usually with hot glue and the molding material is poured over it and allowed to cure. When set, the mold is flipped over and the original removed to reveal the blanket mold ready for casting material.
In this process, the original is fastened inside a mold box or container. The mold material is introduced and filled to about one inch higher than the highest part of the original. When the mold is removed from the box or its container it resembles a block of mold material, thus its name. To remove the original a slice is made on each side of the rubber the going two-thirds down. The mold is spread open like a clam shell and the original is removed. A rubber band is used to keep the mold closed when the casting material is poured.
Two-Part or Complex Mold
For a complicated original, a more complicated mold must be constructed. First one side is molded, followed by the other side. Or if even more complicated addition mold pieces need to be made.
This type of mold is made is the original is thin walled and requires help other than gravity to insert the casting material. A two part mold is often the basis for a rubber injection mold. Once the mold is completed sprue holes are added to allow air and excess casting material to escape. Then a large hypodermic needle (usually a horse hypodermic) is filled with the casting material and squeezed into a hole opposite the sprues until the casting material begins to exit the sprues holes.
Most mold materials require a release agent to prevent item from sticking the original. Silicone often does need a release. Carefully read the instructions on each mold making material so you are aware of what type of release agent you may need.
Most molds are two parts. The first part is the soft rubber which takes the actual impression of the original. This material is thin and flexible and if removed from the original will not keep its original form. So an added rigid layer is added on top of the rubber known as a shell or mother mold. Gypsum plaster and plaster bandages made an inexpensive shell