Many engineers lack familiarity with wire EDM (wire cut).When manufacturers suggest, “This part is better suited for wire cut,” they often accept passively without understanding why. However, the application boundaries of the two processes are clear, and you can make the right choice just by looking at the drawing.
Molds are mainly divided into three major categories by forming processes, with distinct core component differences that directly determine the overall machining strategy and precision standards.
Applied to
injection molding of plastic products. Key components include cavities and cores (concave and convex inserts that define product profiles), sliders (side action structures for undercuts and side holes, sliding outward before product ejection), lifters (angled ejection parts for internal undercut release), inserts (detachable modular components for localized wear replacement and simplified machining), ejector pins (high-precision slender pins for product demolding, with positional tolerance controlled within 0.004mm), sprue bushes and spreader cones (feed and runner structures for molten plastic injection).
Used for blanking, bending and deep drawing of metal sheets. Core parts consist of punches and dies (mating components for
sheet cutting and forming), and stripper plates (functional plates to strip workpieces from punches after stamping).
Designed for high-pressure casting of aluminum, magnesium, zinc and other alloy materials. Similar in structural design to injection molds but with stricter material requirements. These molds feature outstanding high-temperature resistance and erosion resistance to withstand extreme high-pressure and high-temperature casting environments.
🌟Overall Manufacturing Process of Molds
The complete workflow from mold drawing design to mass production is as follows:
- Drawing review
- Material preparation
- Preliminary machining
- Mold base processing
- Mold core processing
- Electrode machining
- Custom mold parts manufacturing
- Dimensional inspection & quality testing
- Mold assembly
- Fitting & hand finishing
- Mold trial test
- Mass production
Mold base processing, mold core processing and custom mold parts manufacturing are three parallel core production lines. Each process is completed independently with dedicated machinery and processing techniques before final assembly.
Mold Base Processing (Mold Framework)
Processing steps: Part number marking → A/B plate (moving & fixed mold plate) machining (parallelism and verticality tolerance within 0.02mm/m) → top plate processing → ejector pin retainer plate processing → bottom plate processing.
Main equipment: conventional milling machines and radial drilling machines. Focus on machining screw holes, cooling water channels, ejector pin holes and other basic mounting holes to ensure assembly benchmark accuracy of the mold base.
Mold Core Processing (Core Forming Inserts)
Processing steps: Six-sided flattening & finishing → rough milling → surface rough grinding → bench work (tapping, part marking) → CNC roughing → heat treatment (hardness up to HRC 48-52) → precision grinding → CNC finishing → EDM electrical discharge machining → wire cutting (low-speed wire cut) → surface polishing → gate and vent groove machining.
