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Study 05 / Precision molding

Smartwatch midframe mold design

The side button and display gasket constrain the smartwatch midframe. The molding review connects those interfaces to wall thickness, filling behavior, air traps and predicted distortion.

Owen Wen · Past engineering project · Anonymized

Cutaway smartwatch showing the midframe beneath the display

Project overview23 drawings

Drawing index

What needed attention before tooling?

The midframe simulation identified localized shrinkage, a small pressure imbalance and a possible air trap on a visible surface. The review judged these risks manageable and identified no defect that would block tooling.

See drawings Volumetric shrinkage and sink estimates · Air trap locations

Drawing series 01

Product Specifications

Smartwatch — Midframe product specifications — Midframe product specifications

Drawing series 02

Midframe Structural Design Details

Smartwatch — Touch panel gasket cross-section — Touch panel gasket cross-section

Smartwatch — Side button cross-section — Side button cross-section

Smartwatch — Display and frame interface — Display and frame interface

Drawing series 03

Injection molding simulation

Smartwatch — Midframe wall thickness review — Midframe wall thickness review

Smartwatch — Local midframe tooling features — Local midframe tooling features

Smartwatch — Core and cavity surface analysis — Core and cavity surface analysis

Smartwatch — Midframe mold opening directions — Midframe mold opening directions

Smartwatch — Core-side tooling directions — Core-side tooling directions

Smartwatch — Two-part runner layout — Two-part runner layout

Smartwatch — PC and ABS blend material properties — PC and ABS blend material properties

Smartwatch — Injection molding process settings — Injection molding process settings

Smartwatch — Sequential filling patterns — Sequential filling patterns

Smartwatch — Animated mold filling sequence — Animated mold filling sequence

Smartwatch — Pressure at switchover — Pressure at switchover

Smartwatch — Flow-front temperature distribution — Flow-front temperature distribution

Smartwatch — Temperature at weld-line areas — Temperature at weld-line areas

Smartwatch — Volumetric shrinkage and sink estimates — Volumetric shrinkage and sink estimates

Smartwatch — Air trap locations — Air trap locations

Smartwatch — Frame and runner simulation comparison — Frame and runner simulation comparison

Smartwatch — Predicted midframe displacement — Predicted midframe displacement

Smartwatch — Deflection in three axes — Deflection in three axes

Smartwatch — Midframe tooling assessment — Midframe tooling assessment