Factors To Consider When Choosing Between Vacuum Forming And Other Processes

by Amy
Last updated January 5, 2023

vacuum forming and injection molding

There are several factors to consider when choosing between vacuum forming and injection molding:

Production volume: Injection molding is generally more suitable for high volume production, while vacuum forming is better suited for low to medium volume production. Injection molding is a faster process and can produce more parts in a shorter period of time. However, vacuum forming is more cost-effective for low volume production, as it requires less initial investment in tooling.
Part complexity: Injection molding is well-suited for producing complex parts with intricate details and tight tolerances. The process allows for the creation of undercuts and internal features, and can achieve tolerances as low as +/- 0.005 inches. Vacuum forming is better suited for simple, shallow parts with less detail and less stringent tolerances.
Material options: Injection molding can be used with a wide variety of materials, including metals and thermoplastics. This allows for the creation of parts with specific mechanical and physical properties. Vacuum forming is generally limited to thermoplastics, and is not suitable for metals or other materials.
Cost: Injection molding typically requires a higher initial investment in tooling, as custom molds must be created for each part design. The unit cost for injection molded parts is generally lower for high volume production, as the fixed cost of the tooling is spread out over a larger quantity of parts. Vacuum forming has a lower initial investment in tooling, as it uses a heated sheet of plastic that is formed over a mold. However, the unit cost for vacuum formed parts is generally higher for low volume production, as the cost of the tooling is not spread out over as many parts.
Lead time: Injection molding has a longer lead time for tooling production and part production, as the custom molds must be designed and manufactured. The lead time for vacuum forming is generally shorter, as the process does not require custom tooling.
Design flexibility: Vacuum forming offers more design flexibility, as it is easier to make changes to the tooling. The process uses a heated sheet of plastic that is formed over a mold, and the mold can be modified quickly and inexpensively. In contrast, injection molding requires more time and effort to make changes to the tooling, as custom molds must be created for each part design.
Surface finish: Injection molded parts generally have a higher quality surface finish than vacuum formed parts. The injection molding process creates a finished part with smooth surfaces and tight tolerances, while vacuum forming can result in surface imperfections and less precise tolerances
Strength and durability: Injection molded parts are generally stronger and more durable than vacuum formed parts. The high pressure and precise control of the injection molding process results in parts with consistent wall thickness and uniform density. Vacuum formed parts may have variations in wall thickness and density, which can affect their strength and durability.

In conclusion, the choice between vacuum forming and injection molding depends on the specific requirements of the application, including production volume, part complexity, material options, cost, lead time, design flexibility, surface finish, and strength and durability.

Vacuum forming and rotational molding

There are several factors to consider when choosing between vacuum forming and rotational molding:

Production volume: Rotational molding is generally more suitable for low to medium volume production, while vacuum forming is better suited for low to medium volume production. Rotational molding is a slower process than vacuum forming, and is not suitable for high volume production.
Part complexity: Rotational molding is well-suited for producing complex parts with intricate details and a wide range of thicknesses. The process allows for the creation of undercuts and internal features, and can achieve tolerances as low as +/- 0.005 inches. Vacuum forming is better suited for simple, shallow parts with less detail and less stringent tolerances.
Material options: Rotational molding can be used with a wide variety of materials, including metals and thermoplastics. This allows for the creation of parts with specific mechanical and physical properties. Vacuum forming is generally limited to thermoplastics, and is not suitable for metals or other materials.
Cost: Rotational molding typically has a lower initial investment in tooling compared to vacuum forming, as it does not require custom molds. However, the unit cost for rotational molded parts is generally higher for low volume production, as the cost of the tooling is not spread out over as many parts. Vacuum forming has a lower initial investment in tooling, as it uses a heated sheet of plastic that is formed over a mold. However, the unit cost for vacuum formed parts is generally higher for low volume production, as the cost of the tooling is not spread out over as many parts.
Lead time: Rotational molding has a longer lead time for tooling production and part production compared to vacuum forming, as the custom molds must be designed and manufactured. The lead time for vacuum forming is generally shorter, as the process does not require custom tooling.
Design flexibility: Vacuum forming offers more design flexibility, as it is easier to make changes to the tooling. The process uses a heated sheet of plastic that is formed over a mold, and the mold can be modified quickly and inexpensively. In contrast, rotational molding requires more time and effort to make changes to the tooling, as custom molds must be created for each part design.
Surface finish: Rotational molded parts generally have a lower quality surface finish than vacuum formed parts. The rotational molding process can result in surface imperfections and less precise tolerances, while vacuum forming can produce parts with smooth surfaces and tight tolerances.
Strength and durability: Rotational molded parts are generally stronger and more durable than vacuum formed parts, due to the evenly distributed wall thickness and uniform density that can be achieved with the rotational molding process. Vacuum formed parts may have variations in wall thickness and density, which can affect their strength and durability.
Part size: Rotational molding is suitable for producing large parts, as the process allows for the creation of molds in virtually any size. Vacuum forming is generally limited to smaller part sizes, as the process requires a heated sheet of plastic that must fit within the vacuum forming machine.
Part shape: Rotational molding is well-suited for producing parts with complex, irregular shapes. The process allows for the creation of molds in virtually any shape, and the finished part can have a uniform wall thickness and density. Vacuum forming is generally limited to producing parts with simple, shallow shapes, as the process uses a flat sheet of plastic that is formed over a mold.

In conclusion, the choice between vacuum forming and rotational molding depends on the specific requirements of the application, including production volume, part complexity, material options, cost, lead time, design flexibility, surface finish, strength and durability, part size, and part shape. Vacuum forming is generally better suited for low to medium volume production, simple, shallow parts with less detail and less stringent tolerances, and smaller part sizes. Rotational molding is generally better suited for low to medium volume production, complex parts with intricate details and a wide range of thicknesses, and large parts with complex, irregular shapes.

Vacuum forming and blow molding

There are several factors to consider when choosing between vacuum forming and blow molding:

Production volume: Blow molding is generally more suitable for high volume production, while vacuum forming is better suited for low to medium volume production. Blow molding is a faster process and can produce more parts in a shorter period of time. However, vacuum forming is more cost-effective for low volume production, as it requires less initial investment in tooling.
Part complexity: Blow molding is well-suited for producing complex parts with intricate details and tight tolerances. The process allows for the creation of undercuts and internal features, and can achieve tolerances as low as +/- 0.005 inches. Vacuum forming is better suited for simple, shallow parts with less detail and less stringent tolerances.
Material options: Blow molding can be used with a wide variety of materials, including metals and thermoplastics. This allows for the creation of parts with specific mechanical and physical properties. Vacuum forming is generally limited to thermoplastics, and is not suitable for metals or other materials.
Cost: Blow molding typically requires a higher initial investment in tooling compared to vacuum forming, as custom molds must be created for each part design. The unit cost for blow molded parts is generally lower for high volume production, as the fixed cost of the tooling is spread out over a larger quantity of parts. Vacuum forming has a lower initial investment in tooling, as it uses a heated sheet of plastic that is formed over a mold. However, the unit cost for vacuum formed parts is generally higher for low volume production, as the cost of the tooling is not spread out over as many parts.
Lead time: Blow molding has a longer lead time for tooling production and part production compared to vacuum forming, as the custom molds must be designed and manufactured. The lead time for vacuum forming is generally shorter, as the process does not require custom tooling.
Design flexibility: Vacuum forming offers more design flexibility, as it is easier to make changes to the tooling. The process uses a heated sheet of plastic that is formed over a mold, and the mold can be modified quickly and inexpensively. In contrast, blow molding requires more time and effort to make changes to the tooling, as custom molds must be created for each part design.
Surface finish: Blow molded parts generally have a higher quality surface finish than vacuum formed parts. The blow molding process creates a finished part with smooth surfaces and tight tolerances, while vacuum forming can result in surface imperfections and less precise tolerances.
Strength and durability: Blow molded parts are generally stronger and more durable than vacuum formed parts. The high pressure and precise control of the blow molding process results in parts with consistent wall thickness and uniform density. Vacuum formed parts may have variations in wall thickness and density, which can affect their strength and durability.
Part size: Blow molding is suitable for producing large parts, as the process allows for the creation of molds in virtually any size. Vacuum forming is generally limited to smaller part sizes, as the process requires a heated sheet of plastic that must fit within the vacuum forming machine.
Part shape: Blow molding is well-suited for producing parts with complex, irregular shapes. The process allows for the creation of molds in virtually any shape, and the finished part can have a uniform wall thickness and density. Vacuum forming is generally limited to producing parts with simple, shallow shapes, as the process uses a flat sheet of plastic that is formed over a mold.

In conclusion, the choice between vacuum forming and blow molding depends on the specific requirements of the application, including production volume, part complexity, material options, cost, lead time, design flexibility, surface finish, strength and durability, part size, and part shape. Vacuum forming is generally better suited for low to medium volume production, simple, shallow parts with less detail and less stringent tolerances, and smaller part sizes. Blow molding is generally better suited for high volume production, complex parts with intricate details and tight tolerances, and large parts with complex, irregular shapes.

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About Ditaiplastic

Ditaiplastic has been working in the field of vacuum forming since 1997 and today has more than 60 large production machines, more than 40 product patents, 80 employees, and a factory covering 12,000 square meters! It is one of the largest suppliers of vacuum forming in China! Kindly visit us at https://www.ditaiplastic.com contact us at amy@dgdtxs.com.cn or WhatsApp: +86 13825780422

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