Thermoforming is a plastic manufacturing process that uses heat and pressure (or vacuum) to form sheets of extruded plastic. Many manufacturers are using it across a wide range of industries including blister packaging for consumer goods, and disposable plastic cups. Heavy gauge thermoforming uses thick plastic to make highly durable components to produce large items such as car dashboards and assembly fixtures.
Because thermoforming doesn’t require extreme heat or pressure, 3D printing (also called additive manufacturing) with FDM technology is a viable alternative.
FDM technology allows you to form naturally porous patterns and requires no secondary machining to pull a vacuum through, which is a necessary step in traditional thermoforming. This has the additional advantage of removing the cooling time required when using traditional tools. The internal porosity of the FDM part slows the absorption of heat, thus reduc the cooling time while increasing throughput.
Kintz Plastics, a plastic fabrication company, successfully used FDM printed tools to form 1/4 inch Kydex T plastic. To ensure success on a heavy gauge thermoforming application, the tool was produced using the strong ULTEM 9085 material, available for the Stratasys Fortus series. Additionally, FDM can produce tools to support the thermoforming process including webkillers and trim fixtures. For these applications, it is estimated that Additive Manufacturing reduces tooling costs as much as 50%-75% over traditional methods.
Xerox utilizes FDM to create thermoforming molds with a faster turn-around time and at lower cost than traditional machining. FDM also allows for complex geometry that would be impossible to achieve by traditional machining. Duane Byerley, a senior model maker at Xerox, describes the problems they used to encounter stating, “It’s very difficult to get the mold exactly right the first time around, so we typically build and test three different designs before we are satisfied.”
A typical example of Xerox using FDM for Thermoforming:
Xerox uses FDM to create fixtures and assembly holders for their production floor, and like other companies, additive manufacturing helps improve existing production techniques. Byerley supports this method and says “So far, we have not found anything we cannot do with FDM.”
Additive manufacturing can give thermoforming companies the competitive edge in the production of manufacturing tools and patterns.