Tooling Selection Guide for Thermoforming
Finding the right tool for your thermoformed part can be a complex decision with potentially large implications on the quality, cost, geometry, and surface finish of your project. Please use the following information to help guide you through the process of matching the appropriate tooling design to the needs of your next thermoforming project.
Some Common Features of Modern Tooling:
Dimensional performance: With temperature control we control a variable that would otherwise affect material shrinkage. If the tool changes temperature the resulting part will not shrink the same and therefore be inconsistent dimensionally.
Heat conduction: The movement of heat from one solid to another. In order to properly cool the formed part we want to move heat evenly from both sides. The side against the tool depends on conduction to remove the heat from the part, transfer through the mold material, and then through the temperature control system.
Ability to withstand pressure: Some materials have less resistance to deformation under pressure.
Tool surface quality: This would be the gloss, texture and presence of surface imperfections. Some tool materials have the ability to be polished or textured depending on the requirements.
Loose piece fitment and performance: In order to form parts with undercuts movable or loose sections are needed in the tool design. (This allows part removal from the tool) These “loose pieces”need to maintain an accurate fit in the mold to minimize the mark-off around the mounting area. They also will move or slide within the mold fit surface. Therefore mold surface and loose piece ware will relate to an increased mark-off or witness line. Some materials ware better and have a longer performance life.
Texture: Texture relating to mold surface is the ability of that surface to be altered with a grain or custom pattern.
What are the Benefits of Temperature Controlled Aluminum Tooling?
While not always the case, you don’t have to look at the information above for long to realize a temperature controlled aluminum tool, whether machined, cast, or both, is most often the ideal tool for a thermoforming application. The reason is that the thermoforming process uses heated plastic and airflow to create the parts for your project and the proper management of that heat and airflow through every stage of production is pivotal in creating a high quality part and efficient process. Simply put, a properly designed aluminum tool with temperature control accomplishes this extremely well.