1. Project background

  Customer demand: A metal casing for a high-end mechanical keyboard that requires lightweight, high precision, high surface smoothness, and supports customized design (such as logo engraving and heat dissipation hole layout).

2. Material selection

  Aluminum alloy 6061: Lightweight, easy to cut, moderate cost, suitable for anodizing coloring.

  Stainless steel 304: High strength and corrosion resistance, but heavy, suitable for high-end customization.

  Engineering plastics (POM): suitable for low-cost and lightweight requirements, but attention should be paid to machining deformation.

  Final choice: The customer chooses aluminum alloy 6061 (balancing lightweight and surface treatment requirements).

3. Machining process

  Step 1:3D Modeling and CAM Programming

  Use SolidWorks or AutoCAD to complete the 3D modeling of the shell, with a focus on optimizing the thin-walled structure (1.5-2mm thickness).

  CAM software (such as Mastercam) generates tool paths, optimizes machining sequence, and reduces idle cutting time.

  Step 2: CNC machine selection

  Choose a four axis CNC machining center (such as DMG MORI) that supports multi-faceted machining and reduces the number of clamping times.

  Step 3: Preparation of raw materials

  Aluminum alloy sheet is cut into 450×160×22mm blanks, with a reserved machining allowance of 0.5mm.

  Step 4: machining Technology

  Rough machining:

  Tool: Φ 8mm flat bottom milling cutter, capable of quickly removing excess material.

  Speed: 8000 RPM, feed rate: 2000 mm/min.

  Attention: Layered cutting (0.5mm per layer) to avoid cutting tool overload.

  Precision machining:

  Tool: Φ 4mm ball end milling cutter (with high surface finish requirements).

  Speed: 12000 RPM, feed rate: 800 mm/min.

  Detail processing: keyboard edge chamfering (C0.3mm), screw hole machining.

  Multi sided machining:

  Flip the workpiece, process the bottom heat dissipation holes and interface slots (requiring secondary clamping, using precision vises and soft claws).

  Step 5: Deburring and surface treatment

  Deburring (edges, holes).

  Surface sandblasting treatment (Ra0.8 μ m), anodized black and blue(thickness 10 μ m).