Versatile Utility Strap — Snap and Lock

Have you ever wanted to pop out the house for a quick moment without the hassle of tagging along a bulky bag or weighing down your drooping pockets? Have you ever gone for a quick jog but worried about how to carry your keys, cards or snack?

Introducing the Versatile Utility Strap — a fully 3D printed wearable with a clever snap-and-twist locking mechanism that allows you to carry your essentials hands-free! This durable, lightweight solution is your perfect companion whether you are running errands, out exploring or powering through your daily workout.

1. Prusa MK4 3D Printer (0.4mm nozzle)
2. Prusament PLA (Pristine White and Galaxy Black)
3. Shapr 3D CAD software (on iPad)
4. Prusa Slicer (for G code rendering), run on a computer
5. Organic supports enabled in slicer

While the concept itself was simple, the design required 2 different mechanisms to be perfected:

1) Adjustable strap with functioning buckle.

2) Turn and lock mechanism interface for variable utilities.

1) For the strap, I uses a series of hinges in a linear distribution to be printed directly, taking advantage of the fact that FDM allows for short bridges to be fabricated, without bonding to the surrounding objects. I need to optimise the length of the strap that could be printed once on a print bed (with an area of about of about 25 cm^2). I split it into two sections, to be combined via the second mechanism. The buckle directly interfaces with the chain links, allowing them to be fed through the ends, pulled over an extruded ledge and finally having one link completely enclosed via the buckle head (a strong 2 point locking system).

2) For the utility interface, I designed a form of bayonet lock with bending ledges (acting as a form of spring) used in trinity to allow for a stable and controlled locking mechanism. This can be added directly onto the desired utility while the counterpart is affixed to the strap.

Having exported the 3mf files from Shapr 3D (a format allowing for a slightly higher resolution than stl), I sliced the model files in PrusaSlicer.

On all parts, I used the following

1. 15% infill
2. 0.1mm layer height
3. Automatically painted on supports
4. Organic support structure
5. No brim

To assemble, snap the different strap components into place (as indicated int he appended image).

For usage, simply feed the band into the buckle and seal in place (once wrapped around arm). Mechanism 2 can be activated even when the strap is already on your arm (quick and easy addition and removal system)!

Attached are all of the STL file for the different components to be printed.

For the chains, repeat links in structure (linear patter 0.9cm spacing) if a longer strap is required.

All good products require extensive field testing and rely on the feedback of users to achieve perfection.

I look forward to your reviews and wish you much success with this new Versatile Utility Strap wearable!