PAX Ergonomic Print-in-Place Carabiner

This print-in-place carabiner by PAX Designs features a smooth ergonomic profile and a flexible latch that prints fully assembled. No supports are needed, and no post-processing is required—just print, flex, and clip. The design is optimized for everyday utility: backpacks, tool belts, keychains, and gear loops.

The carabiner includes a built-in spring latch formed from a coiled flex zone. This zone compresses and rebounds cleanly, allowing the latch to snap shut after insertion. The geometry is tuned for print-in-place success, with clearance gaps and flex tolerances that work on most consumer FDM printers.

Recommended materials include PETG and Nylon for durability and flexibility. PLA may work for demonstration prints but risks cracking under repeated flex. Print flat on the bed with the latch facing upward. Use 0.16 mm layer height for best surface finish and 3–4 perimeters for strength.

This model is not intended for climbing, load-bearing safety, or high-tension applications. It’s perfect for light gear, accessories, and organizational use. The flexible latch has been tested for hundreds of cycles with PETG and shows minimal wear.

Technical Spec Block

• Overall length: ~65 mm
• Thickness: ~7.5 mm
• Print-in-place: Yes
• Support required: No
• Recommended materials: PETG, Nylon, PLA
• Print orientation: Flat on bed, latch upward
• Layer height: 0.2 mm - 0.16 mm
• Perimeters: 3–4
• Infill: 30–40%
• Use case: Keychains, gear loops, tool hangers

• Safety rating: Not for climbing or load-bearing

   

  Edit Suggestions (non-parametric tweaks)

• To change size: scale STL uniformly in slicer
• To stiffen latch: increase wall count or switch to Nylon
• To soften flex: reduce infill or use PETG
• To reinforce coil: add modifier mesh in slicer
• To change grip shape: edit OpenSCAD source manually
• To add keyring hole: boolean cut in CAD or slicer