Hohner Special 20 Magnetic Case

A compact protective case for the Hohner Special 20 diatonic harmonica, designed for durability, portability, and easy printing.
This case consists of two 3D-printable parts (body and lid) that assemble without screws. The hinge uses a simple 50 mm piece of standard 1.75 mm filament as the pin, making assembly quick and tool-free.
The lid closes securely using embedded neodymium magnets, keeping the harmonica protected while allowing fast one-hand opening.
The model is optimized to print without supports and works well on most FDM printers.

Features:
• Designed specifically for Hohner Special 20 harmonicas
• Magnetic closure for secure transport
• Support-free printing
• Tool-free hinge assembly using filament
• Compact and pocket-friendly
• Includes a Fusion 360 file (.f3d) for customization
• Variants Included

Two body versions are provided:
• Standard body – clean minimalist design
• Keychain version – includes a 3 mm channel to attach a cord, keyring, or wrist strap

Hardware Required
• 10 × Neodymium magnets
Diameter: 5 mm
Height: 1 mm
• 1 × Filament hinge pin
Length: 50 mm
Diameter: 1.75 mm

Printing Notes:
• Prints without supports
• Recommended layer height: 0.2 mm
• 4 walls recommended for strength
• PLA, PETG or ABS all work well

Files Included:
• Magnetic case body (standard)
• Magnetic case body with keychain channel
• Magnetic case lid
• Fusion 360 (.f3d) source file for customization

Compatibility:
Designed for Hohner Special 20 diatonic harmonica
(Other 10-hole harmonicas may fit, depending on dimensions.)

Hope you find it useful!
If you print it, please share a make!