Mayku’s guide to pressure forming technology, types, applications, materials, and more
In our previous article, we covered the basics of thermoforming and Mayku’s approaches to the technology with pressure forming and vacuum forming. Here, we’ll take a closer look at pressure forming, its benefits, applications, and more.
What is pressure forming?
Pressure forming refers to the process of using air pressure on a heated plastic sheet to create a mold or part that can exhibit high degrees of detail and texture.
Pressure forming is an enhanced version of vacuum forming. Using the process, the maximum pressure exerted is up to four times higher than vacuum forming.
How does pressure forming work?
First, a plastic sheet is inserted into a pressure-forming machine, so that it sits over a template. It is then heated. Once the proper temperature is reached, up to five tons of pressurized air pushes the plastic sheet over the template, then holds it under high pressure. An air vent removes any excess air. Once sufficiently cooled and hardened, the plastic – now a mold, or a final part after post-processing – is removed from the template to be used as is or to be further processed.
Templates used for pressure forming
During the pressure forming process, tools called templates are used to create molds or parts. These templates can be male (also referred to as “positive”) or female (“negative”).
A male template is convex. When a heated plastic sheet is placed on it, the male template will help form the inner dimensions of the object. A female template is concave, guaranteeing dimensional accuracy on the exterior of the part created, because the plastic sheet is formed inside the template.
Benefits of pressure forming
Pressure forming offers manufacturers and end users a wide range of benefits. Among them:
- Aesthetics. The exteriors of pressure-formed parts or molds can be identical to those created with injection molding, meaning applications with textures, lettering, branding, text, or fine details work well with the pressure forming process.
- Part tolerances. Using a female template results in parts that adhere exactly to its dimensions – and exhibit excellent tolerances – making pressure-formed parts a good choice for assemblies.
- Affordability. Pressure forming rivals injection molding in terms of final product, but can often be achieved more cheaply, thanks to pressure forming’s lower tooling cost.
- Speed. The pressure forming process – including design, template manufacturing, and prototyping – is often faster than injection molding or other manufacturing processes.
- Cost-efficacy. In addition to a relatively low tooling cost, pressure forming is a good choice for creating small- to medium-batch runs of products.
Pressure forming applications
Below are a few of the most common applications that can be created with pressure forming.
- Packaging. Consumer, medical, and pharmacological products packaged in durable plastic are often created with pressure forming.
- Consumer products. Such as device covers, packaging, inset trays.
- Dental. Including tooth aligners, mouthguards, and other
- Automotive. Including dash fascias, plastic panels, and other small (predominantly interior) components.
- Aerospace. Such as drone cases and covers, lightweight covers to protect sensitive components.
- Industrial. Large format moldings, covers, and containers used to hold or protect equipment or tools used in industrial environments.
Pressure forming materials
At Mayku, we focus on four materials for pressure forming:
- High-impact polystyrene (HIPS) – stable, low cost, and impact resistant
- EVA – featuring low-temperature toughness and UV resistance
- PETG – good hardness, chemical resistance, impact resistance, transparency and ductility, making it suitable for food-grade tools or parts
- Low-density polyethylene (LDPE) – can withstand high temperatures, is chemical resistant, soft, and flexible
Other materials used for pressure forming include:
- Acrylic (PMMA)
- Acrylonitrile butadiene styrene (ABS)
- Polycarbonate (PC)
- Polyethylene (PE)
- Polypropylene (PP)
- Polystyrene (PS)
- Polyvinyl chloride (PVC)
- And many more
Vacuum forming vs. pressure forming
Pressure forming is similar to vacuum forming. But whereas vacuum forming uses a vacuum, the process of pressure forming applies up to five tons of pressure to a plastic sheet placed on a template. Because pressure levels are much higher than in vacuum forming, users can leverage pressure forming to achieve higher levels of detail in the parts they create – or use thicker materials for more professional applications. Vacuum forming, meanwhile, is more suited to objects created with thinner plastic – such as product packaging – that require less detail or textured surfaces.
If you’d like to learn more about the differences between pressure forming and vacuum forming, you can read our official comparison: Vacuum forming vs. pressure forming.
Mayku Multiplier: desktop pressure forming machine
The Mayku Multiplier is a desktop 3D former powered by industrial pressure forming technology. It’s compatible with multiple plastic types and thicknesses, and results in highly detailed final parts and molds. When filled with compressed air, the Multiplier’s dome exerts up to five tones of force. This pressure forces air onto a heated plastic sheet into every crevice of a mold, and can capture details of less than <1μm with materials such as EVA sheets.