Do You Know How Much Mold Material You Need?

An artist cannot afford to under-calculate or even over-calculate the quantity of material required for making a mold. EnvironMolds comes to the rescue with a precise computation for each type of mold.

There are many different methods of making a mold. Irrespective of the method or even material used for the mold, it is important to get the quantity of material right.

Mold Making Materials

Professional mold makers tend towards an eyeball estimate of the plaster, polyurethane resin or silicone rubbers required based on the size of the mold box and model. On the other hand, novice artists are not in a position to make an approximate prediction and can just hope that the materials they purchase will suffice.

It is a fact that the ballpark figures can go wrong either way, leading to unnecessary wastage. Indeed, if an artist mixes too much of rubber or resin, he will have to throw away the excess amount. And if the material falls short, the mold will be incomplete and may even require a complete redo.

The good news

EnvironMolds comes to the rescue with scientific formulae for calculating the exact amount of material needed to make different types of molds. They have taken the varying shapes, materials and techniques into account and provide step-by-step instructions on how to calculate the quantity of material.

The computation does involve mathematics and may appear convoluted at first. But the basic premise is straightforward. Measure the dimensions of the mold box (length, breadth and height) and multiply the figures to get the capacity of the box in cubic inches. Similarly, calculate the volume of the model used for making the mold. The formula will be different for cylindrical boxes and models. Subtracting the volume of the model from that of the mold box will give the net volume of material needed.

There are specific conversion constants for converting this volume into grams or ounces of gypsum plaster, polyurethane resin and silicone rubber. For further details check

Armed with this accurate computation, the artist can use the right quantity of say, silicone rubber and later paint the finished cast with silicone paint.


Tags: , , ,

Silicone Rubber in The Rubber Family

Rubbers are extremely versatile in all their forms, but silicone rubber tops the charts in popularity and usage. It is available in different types and the properties and utility tend to vary as well.

Rubber has become a common material in our everyday life. The multipurpose usage encompasses a variety of segments and industries. While natural rubber derived from the tree sap has limited availability, different types of synthetic rubbers have been developed and have properties similar to their natural counterpart.

The most popular among the synthetic variants is silicone rubbers. This is a man-made polymer which comes with a perfect balance of mechanical and chemical properties. It displays excellent electrical resistance, flame retardability, strong chemical stability and tremendous resistance to heat and cold. The inherent flexibility, durability, tensile strength and tear strength is also exceptionally superior. It is translucent and odor free as well.

Silicone Rubbers

Apart from diverse uses in making cosmetics, bath mats, bands, tires, footwear, medication, etc., silicone rubber is commonly used in making molds and casts. The benefit is that it can be easily molded into custom designs and shapes through the pouring, brushing or spraying methods. The silicone molds are suitable for casting plaster, low melt metal alloys and also used in the production casting of resins.

It is the RTV (room temperature vulcanization) silicone that is most suitable for making a mold or cast. This comes in two types – condensation cure and addition cure. The difference lies in the catalyzing aspect – the former uses tin salts while the latter relies on platinum for the same.

These two types of RTV silicone are diametrically opposite – what’s more, they are not even compatible with each other. Choosing the right product based on the individual characteristics and proposed usage is crucial for best results.

It follows that the silicone formulations will feature two parts. The base has to be mixed with the catalyst in the specified mix ratio prior to use. The working time, cure time and pot time and even shelf life will vary from product to product – it is better to check the details before use. Factors like temperature and humidity can also affect the work and pot life of the material.

Again, the same silicone rubber itself is available in different forms to suit varied applications. Apart from the regular rubber formulations, there are distinctive food safe and skin safe options. There is a special translucent silicone mold rubber that is suitable for special effects and duplicating skin surfaces. Faster curing silicone variant is also available.

A major benefit of silicone rubber across its types and forms is that silicone never sticks to anything except itself. This makes it easy to make a silicone mold or cast – a release agent is not required and still demolding is effortless. The rubber will not affect the model in any manner either. A word of caution: artists should refrain from casting the same rubber in a silicone mold as they will never come apart!


Tags: , , ,

The Versatility of Plaster in Arts

Plaster powder is a favored art material as it lends itself well for making molds, casts and even shell molds. Both plaster molds and casts capture the details well and set to a smooth and rigid form.

There are many mold making materials like clay, wax, polyurethane rubber, silicone rubber, etc. Similarly, there is no dearth of choice for casting the mold, it ranges from gypsum and resins to various kinds of rubbers. However, only a few materials can double up for making both molds and casts.

Plaster is one such versatile material that is equally suitable for molds and casts. Additionally, plaster bandages are commonly used for making shell or mother molds too.

Plaster of Paris bandages

Let’s take a look at the multipurpose nature of plaster in the world of mold making, casting and life casting –

Molds – Plaster powder is mixed with water to form a fluid paste. This can be applied over the object or poured into a mold box to form a smooth and solid mold. But care is needed as the plaster can deform easily while it is wet. Yet, the mold will capture crisp details without becoming chalky over time. It can also be carved or tooled easily. The same plaster is often used for restoration works as well.

Life casting artists even use plaster for making molds of the hands. All that the model has to do is dip the hand in the container of plaster mix and hold the pose for a while. The hand can be extracted after a while and a negative impression will be left behind.

Casts – The same plaster slip can be poured into a mold to form a figurine, statuary, earthenware or other art casting. It picks the details well and sets quickly to a smooth and rigid form. The cast remains lightweight making it easy to demold, work on and carry around if needed. It also holds the finish well without chipping or cracking over time.

In fact, plaster is considered the ideal medium for making life casts in both alginate and silicone rubber molds. You can choose a bright white, high definition plaster to get a natural white finish.

Shell molds – Gauze strips that are infused with plaster are the material of choice for backing flexible molds, such as those made of alginate or silicone rubber. The same plaster gauze is also applied directly on the human body to make body molds. While the plaster bandages cannot capture fine details and can release heat, they are still suitable for belly molds, especially for pregnancy casting.

Precautions – Keep in mind that you cannot use generic plaster of Paris for artworks as it tends to get flaky and can develop cracks. Special art plaster is available in art stores. It is equally important to mix the plaster and water properly and in the correct ratio to get a smooth and thick blend. Furthermore, avoid working with plaster on humid days as this will extend the drying period.


Tags: , , ,

Challenges In Life Casting.


It’s not just inanimate objects alone; it is also possible to make molds of humans and animals. However, working on a living being requires a much more careful approach.

A skin-safe mold making material like alginate, special silicone rubber or plaster bandages can be used. The artist has to still work cautiously to avoid causing any kind of harm or even discomfort to the model. For instance, a release agent is essential so that the mold making material does not snag in the body hair and make it difficult to demold.

Going further, the artist has to take immense care when working on the face. The mold making material has to stay clear of the eyes and mouth. It should not clog the nose either as it will become difficult to breathe.

Even the pose of the model has to be carefully planned and tested so that he or she does not feel uncomfortable or even restless. Keeping them calm and relaxed can be quite a challenge for the artist.

However, the artist also has to be prepared for things to go wrong despite taking the best precautions. After all, they are working on a live person and some things will always be beyond their control. Being able to take the disruptions or even failure in stride and being willing to start the work all over again is as important as being skilled at their art!

But once an alginate body mold is ready, it can be easily cast into to create a beautiful life cast. All the artist has to do is clean and prepare the mold before pouring in the plaster (or other appropriate casting material) and the mold will churn out a beautiful replica of the model.

The mesmerizing charm of the life cast will put paid to all the efforts that went into creating this magical art form!

Life casting artists can easily source all their art materials and supplies from EnvironMolds at


Tags: , , ,

Hands Together in a Life Cast

Hand Casting Near Me

Getting a life cast done is generally deemed a lone event. You commission an artist to cast your face, hands, torso or even whole body and that’s that.

However, having other people with you in the life cast can make it more interesting and memorable, isn’t it? But how is this possible?

Let’s consider the possibilities:

How about casting your hands intertwined with your spouse’s to celebrate your everlasting love? It could even be you holding your baby’s hand or a grandparent(s) lovingly clasping the grandchild’s hand. Or how about having siblings’ hands together? In fact, such life casts make for a beautiful gift and are cherished forever.

Another alternative is to cast your pregnant belly with your spouse or older child’s hand cradling the bump? The thought itself can make you tender and bring a tear to the eye.

A ring of hands is another popular life cast with multiple people such as children, parents, grandparents, other relatives or even friends and colleagues holding hands together. The wreath formation can be as big or small as you like and makes for a lovely keepsake.

When casting multiple people together, it is not just about how to make a mold from the body but also how to get the pose right and keep the participants comfortable.

If you wish to try casting intertwined hands or make a ring of hands, all the required materials and supplies can be easily sourced online from The website even provides kits with clear, detailed and illustrated instructions to help you every step of the way.

Leave a comment

Posted by on May 17, 2017 in hand casting


Tags: ,

A Product Called Silicone Rubber


Silicone rubber can be used to reproduce almost anything. Indeed, silicone is very versatile and is a good bet for all types of general mold making applications – be it candles, soaps, refrigerator magnets, ornaments, figurines, model furniture and other prototypes.

Food-safe variations are suitable for making baking containers, food molds, candy molds and ice sculptures as well. These silicone molds lend themselves well for casting with resin, plaster or other materials as needed.

Moreover, silicone rubber can be used for both mold making and casting. In fact, this flexible rubber works as the product of choice for making multiple casts of almost any item. There are skin safe silicone rubbers that prove apt for special effects and duplicating skin surfaces apart from making realistic dolls.

It should be kept in mind that silicone rubber is an expensive material per se. However, what still makes silicone so popular is that it is flexible, durable as well as resistant to water and fire. It does not even stick to anything; therefore you don’t have to seal the mold or apply a release agent unlike other rubbers.

Moreover, silicone molds are reusable and will work well for making thousands of duplicate castings. And the rubber is especially worth the price when casting higher volumes of the same item. On the other hand, as silicone tends to stick to itself, scrap silicone can be recycled in large castings as well.

The only problem is that silicone rubber is susceptible to air bubbles. Therefore, it is better to use a vibrating table or vacuum chamber to remove the air trapped in the silicone.

Silicone rubber comes in two types – condensation cure and addition cure. They have their own unique characteristics and need to be used accordingly.

EnvironMolds offers an exhaustive range of silicone rubber options on its website Apart from the regular offerings, there is SkinRite for realistic mask making and dolls, food safe FDA approved BakeSil for food molds and a skin safe LifeRite for making life castings.

Leave a comment

Posted by on October 17, 2016 in Art & Craft


Tags: ,

Why a Vacuum Chamber is a Must

vacuum_chamber_and_pumpWondering how to rid your molds and casts of those pesky air bubbles that pop up no matter how hard you try to keep them at bay? When all the tapping, shaking and pouring in high, thin streams fails to keep air from getting trapped in the mold making or casting material, it’s time to invest in a vacuum pump and chamber!
Indeed, a vibrating table or even pressure pot can never be as effective as a vacuum chamber. This is because the vibration motion manages to lower the coefficient of friction when the mixture is placed on it. Air bubbles will rise to the surface and can be popped easily, but this does not mean that the material is completely deaired.
On the other hand, a pressure pot merely squeezes the trapped air bubbles to microscopic sizes. Now when the material leaves the pressurized vessel, the bubbles will mostly regain their original size. This is especially true for soft rubbers as they are stretchable; the bubbles will expand again to form warts on the surface or even cause the mold/cast to collapse.
Therefore, using a pressure pot is effective only for resins, as the mold or cast will set to a rigid non-flexible form. Here again it is advisable to leave the mold or cast inside the pressure pot until it has cured. Casting resins under pressure will deliver a bubble-free casting.
Therefore, only a vacuum pump with vacuum chamber can completely deair both silicones and polyurethane resins for completely bubble-free molds and castings.
EnvironMolds stocks top quality and cost-effective vacuum pump with vacuum chamber that is a must-have for every art studio. Simply place the mixed rubber/resin in the vacuum chamber and switch on the pump. The material will rise for some time before leveling out to show that air has been completely removed. Now your material is ready to deliver perfect molds and casts!

Leave a comment

Posted by on September 20, 2016 in Art & Craft