Keyring Engagement Ring Case (Body + Domed Screw Lid)

Create a compact, two-piece 3D-printable protective case for an engagement ring, designed to attach to a keyring. Overall shape * Rounded cylindrical capsule with a gently domed lid. * Approximate external diameter: 37 mm. * Approximate total height: 40 mm, excluding the keyring. * Smooth exterior with rounded edges. * The bottom must be flat so it can sit/ stand on its own. Main body * Hollow cup-shaped container with a flat internal and external floor. * Enough internal space for a single engagement ring and a soft protective insert. * Rounded internal corners. * Must have a central stem, 8mm in diameter than protrudes the lid once screwed on, by 8mm. * There must be transverse hole that is 4mm in diameter that goes through the stem for a split key ring. * The bottom edge of this hole must align perfectly with the upper edge of the lid, once screwed into the base. Lid * Separate domed lid that screws onto the main body. * Include a functional male/female threaded closure. * There must be a hole in the middle that allows the stem from the base to protrude. Secondary locking mechanism * The lid must screw fully closed with the stem hole accessible. * A metal split key ring will pass through the hole. * When installed, the key ring must physically prevent the lid from rotating sufficiently to unscrew. * Keep the keyring mechanism separate from the threaded surfaces. Prototype requirements * Generate the lid and body as separate solid parts. * Prioritise functional geometry and ease of 3D printing over cosmetic details. * Make the main dimensions adjustable. * Export both parts as STL files and, if supported, a STEP file. This is an initial concept model for testing, not a certified production design.

Parameters

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