Silicone Material Calculator

Calculate the amount of silicone needed to make a silicone mold.

The amount of liquid silicone rubber required for making a silicone mold can vary depending on the project. To determine the necessary quantity, you need to consider the mold's depth, width, length, and the desired silicone thickness. We have provided a calculation method to help you more accurately estimate the required liquid silicone rubber amount. This will ensure that you have enough material to complete your project while minimizing waste.

Calculation Steps:

1. Calculate the Required Material Volume:

Required Material Volume = Mold Container Volume - Model Volume

Note: In practical situations, for irregular models, you can estimate an approximate volume.

2. Calculate the Required Material Weight:

Required Material Weight = Silicone Density x Required Material Volume

Note: The density of RTV-2 silicone materials is typically taken as 1.2g/cm³ when calculating the weight of the required material.

3. Add Loss Quantity:

For the sake of safety, an additional 5% to 10% loss quantity should be calculated, as there may be losses of liquid silicone residue in the mixing process, such as on the mixing container and stirring rod.

Volume Calculator

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Rectangular
Cylindrical

Mold Box Volume - Rectangular

Formula: Volume = Length x Width x Height

Note: To ensure the durability of the silicone mold, it is recommended that each side of the mold has a thickness of approximately 0.5 cm. This means that the distance between each side of the mold frame and the surface of the master pattern should be about 0.5 cm. Additionally, when pouring the silicone, it should exceed the highest point of the master pattern by approximately 0.5 cm.

For example: The dimensions of the mold box are: Length 6 cm, Width 4 cm, Height 3 cm. The dimensions of the master pattern are: Length 5 cm, Width 3 cm, Height 2 cm.

Mold Box Volume: 6 cm x 4 cm x 3 cm = 72 cm³

Master Pattern Volume: 5 cm x 3 cm x 2 cm = 30 cm³

Required Silicone Volume: 72 cm³ - 30 cm³ = 42 cm³

Required Silicone Quantity: 1.2 g/cm³ x 42 cm3 = 50.4 g

Estimated Loss Quantity: 2.52 g - 5.04 g

Actual Required Quantity: 52.92 g - 55.44 g

Mold Box Volume - Cylindrical

Formula: Volume = π (3.14) x Radius Squared x Height

For example: The dimensions of the mold box are: Length 6 cm, Width 4 cm, Height 3 cm. The dimensions of the master pattern are: Length 5 cm, Width 3 cm, Height 2 cm.

Mold Box Volume: 3.14 x 4 cm x 4 cm x 3 cm = 150.72 cm³

Master Pattern Volume: 3.14 x 2 cm x 2 cm x 2 cm = 25.12 cm³

Required Silicone Volume: 150.72 cm³ - 25.12 cm³ = 125.6 cm³

Required Silicone Quantity: 1.2 g/cm³ x 125.6 cm³ = 150.72 g

Estimated Loss Quantity: 7.536 g - 15.072 g

Actual Required Quantity: 158.256 g - 165.792 g

Calculation Formula
Example

For larger-sized and intricate models like statues, the brush-on technique is commonly employed for mold making. When calculating, the model is divided into multiple parts, and the surface area of each part is calculated separately. Then, the surface areas are added together to obtain the total surface area. Finally, multiplying it by the thickness of the brush-on silicone, which is usually around 2-3mm, will give us the required volume.

For example, if a statue is divided into 5 parts, each part measuring 5cm in length and width.

Each Surface Area: 5 cm x 5 cm = 25 cm²

Total Area: 5 sides x 25 cm² = 125 cm²

Total Volume: 125 cm² x 0.3 cm = 37.5 cm³

Required Silicone Quantity: 1.2 g/cm³ x 37.5 cm³ = 45 g

Estimated Loss Quantity: 2.25 g - 4.5 g

Actual Required Quantity: 47.25 g - 49.5 g

Build the mold frame according to the shape and size of the master pattern, and then pour water (fine sand or rice grains are also options) into the sealed mold frame. The amount of water used represents the required volume of liquid silicone for the project.

Note: The density of water is 1.0g/cm³, and the density of silicone is 1.2g/cm³. It is safer to calculate a little more when budgeting. Also, before pouring the liquid silicone please ensure that the water is completely dry to avoid inhibiting the curing of silicone.

Silicone Material Calculator

Pour-On Mold Calculations

Brush-On Mold Calculations

Other Easy Methods

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