What’s the Difference Between Vacuum Forming and Thermoforming?

by | Oct 30, 2021 | Industry

Difference between Vacuum Forming and Thermoforming

The terms vacuum forming and thermoforming are often used interchangeably. However, the processes for each might be different depending on the professional who is using them.

 

What is Thermoforming?

 

Generally speaking, thermoforming is a process where plastic is in sheet form and then heated until soft. It is then placed in a mold. Thermoforming is essentially a generic term and in most cases will also include vacuum forming, twin sheet forming, and pressure forming in order to create a coverall type of molding.

 

Thermoforming is the technique of softening a thermoplastic sheet by heating it. The sheet is stretched and controlled across a single-sided mold. It then cools to the appropriate form. Vacuum-forming, pressure-forming, and mechanical forming are the most popular ways for getting the sheet to conform to its ultimate shape. Thermoforming has several applications and may be utilized in a variety of sectors.

 

The Benefits of Thermoforming

 

Thermoforming has several benefits that make it preferable to other forms of molding. Among these benefits are the following:

 

  • The capacity to make many final components out of the same material

 

  • It enables for the early discovery of potential design and fit flaws, saving time and money.

 

  • It is useful when working with huge pieces.

 

What is Vacuum Forming?

 

Thermoforming and vacuum forming are inextricably linked. Vacuum forming is, in reality, a sort of thermoforming. There are, nevertheless, some significant variances. As a result, it is critical to be able to discern between the two. Vacuum forming necessitates a few extra steps that cause the plastic to adhere to the mold during the forming process. Vacuum forming also has very limited applications. It is typically used in applications that need shallow plastic pieces to be molded into cavities. Other significant vacuum creating facts to know include:

 

Materials that are appropriate

 

Fewer materials are appropriate for vacuum forming applications. The following are the ideal materials for this purpose:

 

  • HIPS

 

  • Thermoplastics

 

 

Applications

 

Because vacuum-formed components may replace complicated manufactured sheet metals, fiberglass, or plastic injection molding, they are excellent for particular applications. Vacuum formation may be seen in a variety of areas, including:

 

  • ATMs

 

  • Kiosks

 

  • Medical imaging enclosures

 

  • Diagnostic equipment

 

Vacuum forming problems

 

Despite all of its advantages, vacuum forming does have certain disadvantages. Some of the most typical issues are:

 

  • The molds absorb moisture quickly, causing bubbles inside the inner layers

 

  • Webs can form around the mold, affecting the final result

 

  • Objects can attach to the mold.

 

 

Pressure forming is similar to vacuum forming where the sheet is heated up and then positioned onto the mold. However, in pressure forming another piece of tooling is used in order to push the sheet into the shape.

 

 

Essentially, vacuum forming and thermoforming are the same things, just different techniques are used based on industry.