Showing posts with label mold making rubber. Show all posts
Showing posts with label mold making rubber. Show all posts

Working with Mold Making Latex Rubber

Latex rubber molds are easy to make, economical, last for years and can be used for multiple castings. Following are a few pointers to be kept in mind when making a latex mold through the brush-on method.

Latex rubber is considered the best material for making molds – it trumps in terms of affordability, durability, reusability, convenience and more. The molds turn out flexible and can be used to capture a negative impression of statues, figurines, plaques, life castings, etc. The most complicated models can be easily captured down to the minutest details.

In fact, latex is formulated in liquid form to allow ease of use for making molds. Take Kreemtex Premium Liquid Latex for Mold Making for instance. The liquid rubber can be brushed, sprayed or poured over the model to capture its shape in a mold. The thick consistency makes it easy to apply and also allows for easy coverage with minimum coats. However, if the rubber seems to be too concentrated, it can be thinned to a more viscous consistency by adding distilled water to get the requisite runniness.

Latex rubber should be stored in a cool place; it should not be allowed to freeze as this will make it unusable. It should be stirred properly prior to use. In case the ammonia content of the latex has evaporated or diminished over time, it is better to replenish the same before use. However, the ammonia should come from a chemical store and not grocery ones as the latter contain more of soap. Add a bit of ammonia at a time till the original texture is obtained.



How to apply?


Brushing multiple coats of latex over the model is the most common method of making a latex mold. Some models may have to be sealed prior to late application. Applying a suitable release agent is preferable.

Start from the top of the model and brush the latex in a thin and even coat while making sure that all air bubbles are brushed out. From the bottom, continue out to form a two inch flange which will serve handy when using the mold for casting.

Allow each coat to dry properly – it should be dry to the touch - before starting the next one. Here it is advised to apply the liquid latex in a checkerboard fashion by alternating the direction of application. This will ensure that the mold does not shrink and the dimensions do not change. A heat source can be used to hasten up the drying between coats.

Once the desired thickness is built up (will take 10 to 12 coats at least), the mold can be removed from the model and allowed to dry further for 72 hours or so. Curing in a warm atmosphere to ensure proper strength and toughness to the mold.

Molds made from Kreemtex Premium Liquid Latex for mold making will be stable, tear resistant and can be used to cast different materials. The outcome will be perfect as long as the proper procedure and precautions are followed!

Making Latex Molds and Casts

Latex rubber is a popular choice for making both molds and casts. Latex has several useful properties and it is also relatively easy to make both latex molds and casts by following the right procedures.

Liquid latex rubber is a versatiles material that is considered tough, durable and economical as well. It lends itself well for various applications in the fields of mold making and casting.

Latex molds capture details well and are usually used to make plaster and resin casts. They are also handy for casting abrasive materials like concrete as the mold will not tear despite the coarseness. The latex can also be applied on architectural details on the walls or even ceilings without the latex running off. This works especially well for making molds for restoration works.

Latex casting is usually used for making hollow molded rubber articles, toys, balls, imitation pottery, display items and flexible props. Liquid latex is popularly used for mask making as well as special effects works like wrinkles, scars and gashes for theatre, television and films. It is even commonly used as an adhesive for bald caps.

Apart from this, latex is useful for slushing casting clays for ceramic works and for coating polystyrene and other fabrics and even tools. This forms a protective and water proof coating on the items. It even allows for better handling and insulation for the tools.

How to do?

It is easy to use latex rubber for making molds and casts. The most common method is dipping for mold making and pouring for casting - No elaborate process or expensive molds are required.

Latex molds are created by dipping the model directly into the latex rubber itself. Simply dip the model into the container to get a uniform coating and then let it dry. Repeat the procedure 10 to 12 times to build up the adequate thickness. Alternatively, the latex can also be painted on the model multiple times, while allowing each subsequent coat to dry properly.

The procedure for making latex casts is also quite similar. Here, the latex rubber is poured into the mold and allowed to sit for some time. Then the rubber is poured out again. A thin film gets deposited on the inner side of the mold and will dry to form a flexible cast. Keeping the latex inside for a longer time or repeating the procedure will increase the thickness of the latex cast.

Usually plaster molds are preferred for making latex castings. This is because the porous plaster will absorb the water in the latex and allow it to cure to form a cast. Therefore, latex and other molds are generally not preferred for latex casts.

Demolding liquid latex molds and casts is also simple as they can be easily peeled off the model or mold. However, it is advisable to dust the latex surface with talcum powder before demolding, else the latex will stick to itself. Latex casts can be painted with special latex paints to get the desired finish.