Check out these two book binders I just designed

The hinge to be held together using a leftover piece of 3D printer filament

Design 1: Elastic Band Binder

• Paper Size: Holds 148mm x 210mm essentially an A4 sheet folded in half 
• How it works: You clip elastic bands to the center of the binder to hold the paper in place.
• Assembly: Just use a piece of 3D printing filament as the hinge pin to hold the binder together.

Design 2: Pin & Bar Binder

• Paper Size: 150mm x 100mm paper.
• How it works: Use a standard paper punch on your pages, then slide them onto the built-in pins inside the binder.
• Assembly: It features a printed bar that locks down over the pins to keep the paper secure.

• 🛠️ Printing Settings & Tips

• Material: PLA 
• Infill: 10-15% gyro or grid
• Supports:  Not Needed
• Layer Height: 0.2mm