Heavy Duty Spring Clip

Stop settling for flimsy, one-piece clips that lose their tension after a week on the bag. This heavy-duty utility clamp features a unique snap-in spring design that provides a professional-grade grip and incredible durability for your workshop, kitchen, or laundry room. Just print, snap the core into place, and experience the most satisfying, high-tension "click" in 3D printed organization.

This clip has many potential uses: clothes pin, chip clip, utility clip, utility clamp, etc. Use your imagination. It is remarkably strong for an entirely 3D-printed mechanism.

Recommended Print Settings

• Layer Height: 0.2 mm
• Wall Loops: 4 perimeters
• Top/Bottom Shells: 8 layers
• Infill: 15% Cubic
• Orientation: Print on side (edge)
• Supports: Required (Manual or Auto-tree)
• Support Interface: PLA (if printing clip in PETG)

These settings are optimized to ensure the clip handles high mechanical stress. Four wall loops provide the necessary structural "meat" for the integrated hinge, and ensure the handles don't flex or delaminate under the high tension provided by the snap-in spring.

Recommended Filament & Materials

• Primary Material: PETG (Highly Recommended)
• Support Interface: PLA (Optional for clean removal)
• Hardware: None (100% 3D Printed)

While you can print the clip body in PLA, PETG is strongly recommended for the spring component. PETG’s superior fatigue resistance and elasticity allow the spring to maintain its "bite" over hundreds of uses, whereas PLA will eventually undergo plastic deformation (creep) and lose its grip.

Assembly & Usage Instructions

1. Remove Supports: Carefully clear support material from the hinge gap and the interior handle cavity.
2. Verify Hinge: Ensure the print-in-place hinge moves freely.
3. Insert Spring: Slide the spring into the back of the clip (between the handles) until it snaps firmly into the designated grooves.
4. Final Lock: Once seated, the spring is designed for a permanent high-friction fit and should not be easily removed.

The internal geometry uses a tight-tolerance snap-fit to ensure the spring never slips during use. By integrating the hinge into a single-piece body and utilizing a separate high-tension spring, this design eliminates the common failure points found in standard "all-in-one" print-in-place clips.

Functional Practicality & Novelty

Standard 3D-printed clips usually rely on the "living hinge" or thin plastic flexures that weaken almost immediately. This model solves that "unmet need" by decoupling the hinge and the spring.

In a high-use environment like a garage or a woodshop, you need a clamp that can hold heavy tarps or tool bags without slipping. This design mimics the mechanical leverage of an industrial clothespin, providing a level of "clamping force" that simple one-piece prints cannot match. By printing on the side, the tension acts perpendicular to the layer lines, preventing the clip from snapping along the grain.

I needed a pretty low profile clip that I could use for later projects. AndyCar's Bag Clips was a good starting point. I wanted it to print standing on the edges, so that when tension is applied to the clip, it will be perpendicular to the strong layer lines. In order to accomplish this, the clip needed a built-in hinge that could print in place. I designed that hinge, and joined the two halves of the clip together with it. I also wanted the spring to be a bit stronger. So I changed the geometry of the spring to make it a bit tighter. 

I strongly discourage printing the clip with PLA. You might be able to get away with printing the clip itself with PLA. But the spring won't work well if printed in PLA. The best use of PLA for this model is as a support interface, and that is all.