One-Hand Ratchet Lace Closure

Update :

• Design knob added for small model

• Tested M3 base which can be fix with M3 countersunk 6/8mm without feeling on foot.

One-Hand Ratchet Lace Closure

Traditional shoelaces often require two hands, finger dexterity and the ability to bend comfortably.

This project replaces knot tying with a fully printable ratcheting closure system. Turn the knob to tighten the shoe and pull the knob to instantly release the tension.

The design was developed to address a personal accessibility challenge. Due to CRPS (algodystrophy) affecting my right arm and shoulder, combined with spinal injuries, tying shoelaces became difficult and uncomfortable. The goal was to create a closure system that could be operated using one hand while wearing the shoe.

Features

• One-handed operation

• Turn to tighten

• Pull to release

• Fully printable mechanism

• Uses standard M3 hardware

• Small and large knob versions included

• Suitable for shoes, hiking footwear and other lace-based applications

Components

Printed parts:

• Base (sew or M3 version)

• Spool

• Click mechanism

• Spacer

• Spring

• Knob (design or standard)

Additional hardware:

• M3 nuts

• M3x20 screw (small version)

• M3x25 screw (large version)

• M3x6 or 8 countersunk head (no sew version)

Materials

The prototype was successfully tested using:

• PA12 for the click mechanism

• PLA for the remaining parts

• 1 mm UV-resistant cord

The lace is mechanically anchored inside the spool and does not rely on friction to prevent slipping.

Testing

The prototype has been tested during everyday use, including several hours of walking and shopping, without accidental release or noticeable loss of tension.

Print Settings

Recommended:

• 0.16 mm layer height

• 3 to 4 perimeters

• 20 to 40% infill

• Only support where needed

• Arachne mode on

Recommended Materials

• PLA for general use

• PETG/ABS/ASA for improved durability

• PA12 recommended for the click mechanism

Cord

Designed around approximately 1 mm cord or small paracord-style line.

Assembly

1. Insert the cord into each base entry hole and then into the spool and secure with knots.

2. Install the spool into the base.

3. install and glue the spring (lips toward opening) into the knob, 4 markers/guides are present.

4. Install the spacer, mushroom head toward spring middle hole.

5. Install and glue the click mechanism into the 3 spring side lips.

6. Assemble the knob to the base.

7. Secure with the M3 screw and nut.

8. Sew/screw the base tabs onto the shoe.

Attribution

This project is inspired by the Adaptive Skiing Prosthesis for Children created by Zitouni and published under the Creative Commons Attribution 4.0 International (CC BY 4.0) license.

The original design was developed for adaptive skiing prosthetics. This project adapts some of the underlying mechanical concepts into a shoe closure system focused on accessibility and one-handed operation.

Many thanks to Zitouni for sharing the original work and making derivative accessibility projects possible.