Plastics: External and Internal Actions

Part Six of the 9-Part Mold Design and Moldmaking Training series, created with help from many of the world’s leading tool manufacturers and suppliers, focuses on external and internal actions. Topics detail slides, core pins, and lifters; unscrewing and expandable cores, inserts; dissolvable cores; preload and seal-offs.

Any worker who is or who is training to be a tool designer, mold maker, engineer, part designer, or anyone involved in the tool procurement process.

• Slides
• Actuators
• Preload
• Core Pins
• Lifters [External Action]
• Expandable Cores
• Lifters [Internal Action]
• Unscrewing Cores
• Collapsible Cores
• Inserts
• Dissolvable Core Process
• Seal Offs
• Material Considerations

• Know the uses and components of a typical slide assembly.
• Recognize the different actuators used for controlling a slide.
• Describe how ‘preload’ is used to counteract extreme pressures.
• Know the uses and components of a typical core pin configuration.
• Know the uses and components of a typical lifter used as an external action.
• Identify the two types of expandable cores used as an external action.
• Understand that lifters (internal action) may require part reconfiguration.
• Understand how to remove threads from the inside of molded parts.
• Understand how to remove undercuts from the inside of round cores.
• Understand when inserts are needed as either an internal or external action.
• Recognize how polymer is molded over a dissolvable metal core to produce parts.
• Know how to keep material from flowing around actions to prevent flash.
• Understand many of the material considerations so that wear can be minimized.