Adjustable Phone Stand

As part of the final project for the MAT594X course, I tried making an adjustable phone stand. It has some different parts which I will be covering in the following sections.

For getting adjustable angle in the phone stand, I thought of using living hinges. Living Hinges are useful where you want to bend the material like wood. It is usually fabricated using laser cutters. But in my case I used 3D printers to fabricate them. I used the following video as my main guide for creating living hinges using 3D printers

https://www.youtube.com/watch?v=nVat2y4bJ7s

The following websites provided a great insight on how to design living hinges

https://www.ponoko.com/blog/how-to-make/how-to-des...

https://www.instructables.com/Living-Hinge-Smart-P...

https://obrary.com/collections/popular-designs/pro...

https://futurearchi.org/t/lattice-hinge-design-wor...

https://www.grasshopper3d.com/forum/topics/help-on...

I will be mainly focussing on straight type living hinge design.

So I started with a straight living hinge design in Fusion 360. I made the living hinge on a rectangular slab of thickness 2mm. The initial design which I did had very small gaps (about 1.8mm) between the lines of the hinges making it extremely flexible and also gave the slab ability to extend. The first two images represent that. Then I realised that I needed to increase the distance between the straight cuts to get more rigidity. Then after increasing the distance between the cuts (about 3.6mm), I get the desired flexibility for the 2mm thick rectangular slab. It also maintains its curvature as shown in the last two images.

Now with the living hinge designed, I have to come up with a design for the phone stand. Before I start with the phone stand design, I needed to figure out the limit for the 3D press fit kind of design for the rectangular slab which had that living hinge. This rectangular slab will connect both the top part and the base of the phone stand. To test out the press fit, I created a small hollow rectangular slab with different sizes. I found having an offset of 0.1mm to 0.15mm is a good fit for my 3D press fit design.

With the press fit decided, I needed to design a phone stand which will house the phone. The first two pictures show the design I came up with. The design was easy to make but it was hard to 3D print. I first sliced the whole model lying down in Ultimaker Cura, with support structure. It was hard to remove the support structure and it messed up the actual model. It also broke off one of the supports. Then I placed it upside down and tried slicing it with Cura having supports, the last three images. This also did not work properly, as one of the legs were too small and were not sticking properly to the printer bed. I tried with a dough, rubber bands and even Krazy Glue, it did not work at all. So I decided to do away with this design and go with a modular one.

Since I had tested the 3D press fit limitations, I had a general idea going with dimensions of the slots. I first made the main rectangular connector part, then I designed the parts of the phone stand, which included the two hook kind of structures, and other supports for the phone. I made the support parts connect to that main connector via press fit. This is how it looks.

Now with phone stand's upper part in place, I needed a base which could hold the upper part. I designed the base like a rectangular slab, with ridges at the top on which the phone stand's upper part will rest. Fitting it in different slots will allow for the phone to have different angles. I also made two extra slots, so that I could fit in some sort rectangular rod, to give the base more support.

After fitting all the parts together, the phone stand looks like this. It works pretty well for my purpose and I can adjust the angle as well now. The only drawback is that since the living hinge is providing the back support, it makes the phone wobble a bit.

Following are the files that were involved in this project.