A3–2D Object Prototype

Laser Cut Phone Stand


Background Research

A pretty simple endeavor: make a stand that I can use as a holster for my phone while filming things, using CAD and a laser cutter. Yet, I hadn’t touched anything in CAD since middle school and I’ve never used a laser cutter.

I was the user for this tool, so I didn’t need to do as much background research as with the previous projects (apart from learning Rhino for CAD and how to use the laser cutter). The stand was however I wanted, and I didn’t need much apart from a stand that could hold my phone at a 90° angle.

I recalled a phone stand that I received at a career fair. A simple piece of plastic, it folded flat, but provided a nice viewing angle. However, it relies on a piece of rubber that grips the phone. Without it, the phone would slide off. I didn’t intend make a grip, so this told me I needed to find a design that would hold the phone in place.

My next step was to analyze existing phone stands. A quick search yielded a few different designs. One that caught my eye was made of folded cardboard.

Source: http://theideaking.blogspot.com/2013/11/6-diy-cell-phone-stand.html

I liked the simplicity of the cardboard stand, so I decided to try it out really quickly. From this pictured, I tried to create the slat of cardboard out of paper. It appears to be a single solid piece of cardboard, bent into place.

There were some issues with this design. I didn’t like the shallow angle of the phone stand — I really wanted a 90° holster. Additionally, the contortion needed to get the slats in the right place put heavy strain on the material. With paper as the material, the bending and shaping was fine, but I feared that thicker materials would not bend properly or get creases.

Summary:

  • 90° angle holster
  • Too much torsion can break materials
  • Can’t use grippy material

Design

Paper Version

I knew that I wanted to create a 90° angle holder. I wanted as few as pieces as possible, and I wanted to fit my phone, a Moto X 2014, nicely. I decided that I wanted the holster to be very spartan — little material and super-portable.

First verification of structure

I started by folding paper to check how folds and joins would work. I quickly stood up a piece of paper with two slats, as my first verification of the structure. It stood up quite nicely and was actually quite sturdy.

The cradle design, with side slats

Next step was to create a holster. I decided that a cradle would be ideal — the weight of the phone would bend the U-shape further and provide a narrower gap that would adjust per phone. Furthermore, the support slats would provide an edge to the cradle section, keeping it from falling over.

Design of the cradle slat

I created the design by envisioning how it would be flat. The cradle was the key — the interlocking sections of the support slats would only be made once the width of gap of the cradle was made. And the gap of the cradle could only be measured once it was cut into the material with the correct scoring.

I designed for my phone, a 2014 Moto X, dimensions 1 x 10 x 22cm.

Laser Cut on Chipboard

Screenshot of Rhino during the 1st iteration

After feeling relatively confident with my sketches and folded paper prototypes, I moved to the chipboard laser cutter. The outline was done on Rhino 5.0. The laser cutter material was 12mm thick pressed chipboard.

To create the bend of the cradle, I needed to create scores along the edge of the bend. Using the score layer (blue), I marked 10 score lines 1mm apart on the edge of the bend, for 10cm, for a bend area of 1 x 10cm.

I made a mistake with my first laser cut design — I accidentally assigned the entire length of the middle section to 10cm instead of just the cradle section. As a result, the slat was quite too small.

However, this first draft gave me the chance to test the number of scores and measure the kerf distance for the support slats. The gap for the phone area at 10 scores was a perfect fit for my phone at 13mm wide.

I then rescaled middle slat’s size to reflect the full width of the phone, as well as raised the cradle walls to add stability.

Laser cutter creating the 3rd iteration (16x speed)

My second print worked out much better. The size worked for my phone and the fit was tight. However, the kerf lengths were off. I needed a total of 6cm joints on either side for the support joints, but I had made it 1cm on the cradle side and 5cm on the support side. I thought it would be provide better side support, but it made the supports flimsy.

Screenshot of Rhino during the final iteration

My third and final iteration used kerfs of 3cm each, 13mm apart (the cradle gap width). This created a sturdy and solid phone holster.

Summary:

  • Paper versions to test general structure
  • Rhino rendering for 2D
  • Chipboard iterations to hammer out details

Future Work and Lessons Learned

Future work would probably to be to test how essential each dimension of the stand is. The support stands have a wide base, to ensure stability. However, their size relative to the whole stand is a bit large and unsightly, so I would like to try to curve or round off the corners.

I would like to incorporate the ability to hold the phone in a horizontal view. I could do this by extending the center section to hold either the 22cm or 10cm, and make the distance between supports adjustable with additional kerfs.

Foremost, I learned how to use Rhino for 2D rendering, how to transfer Rhino models to the laser cutter software, and how to use the laser cutter.

I was able to apply the lessons that I learned in the Model Prototype by starting with paper as a low fidelity before jumping to the chipboard. Rendering, exporting, and printing takes time, so it’s best to form the general structure with folded and cut paper.

At the same time, medium fidelity chipboard was great for figuring out joints and other material-specific issues. Paper would not allow me to test the scoring or make measurements that I was able to do with the first and second chipboard iterations. If I were to move to more expensive materials, chipboard would serve as an excellent proof-of-concept material.

Summary:

  • Non-essential future improvements
  • New skills: Rhino and laser cutter
  • Medium fidelity gives more targeted testing insights