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11. Mold Metal Adjustments - Centering Process - Validation procedure for injection molds

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The eleventh step in validating a injection mold with the overall process shown in injection mold validation flow chart is Mold Metal Adjustments - Centering Process . The steps before: 1. Mold certification  2. Dry cycle mold 3. Process stability test 4. Gage repeatability & reproducibility (R&R) test  5. Mold viscosity test 6. Balance of fill analysis 7. Gate Freeze Test 8. Commissioning (multi-cavity analysis) 9. Design of Experiments (DOE or DOX) 10. Qualification (Process Capability Study)  Purpose: After achieving a capability ratio (Cr) of < 0.75 for key part dimensions, the mold metal is re-cut to center the average to match target. Changing the metal in the mold based on the optimal process, even if it means remaking mold components due to non-metal safe conditions, is preferred vs. changing the process to get the dimensional variation centered. Otherwise the process may not be capable of achieving part specified tolerances. The centering proces