This Instructable shows you an innovative way how to make a DIY phone case from soda cans. The method presented here can be used as a general approach how to make any kind of nice boxes from soda cans (see video: DIY phone case from soda cans).

In a previous Instructable (see Instructable: Flatten Soda Cans) I showed how to flatten soda cans with the use of an electric iron. The same principle of applying heat to soda cans can also be used when first forcing soda cans in a customized shape using spacers and then place it in an oven. After the heat treatment in the oven, the spacers can be removed and the soda can keeps the desired shape permanently.

In addition you can also remove the ink (see Instructable: Ink Removal From Soda Cans) from the soda cans in order to make it look cooler!

The project was done using a Samsung GALAXY A5 whereas the Huawei P-10 or the Samsung GALAXY S9 was working as well. In case you have a different phone you have to play around with different size soda cans and the thickness of the foam rubber.

If you like that project please vote for me in the "Trash to Treasure" contest?

Step 1: Parts List

For that project you need the following items:

Materials:

Small soda can (diameter 53 mm): Is used as the bottom part of the phone case
Middle size soda can (diameter 58 mm): Is used as the lid for the phone case
Large soda can (diameter 66 mm): Is used to make the second type of spacer
Foam rubber (2mm thickness): Is used to make the closure in the bottom part and the lid of the phone case. Moreover it is used as the lining material inside the phone case
Popsicle sticks (150mm x circa 17-18mm): Around 10 pieces are needed to make the first type of spacer

Tools:

Utility Knife
Scissors
Stapler
Wooden block 1 (25mm x 13mm x 64mm)
Wooden block 2 (9mm x 13mm x 64mm)
Ruler
Contact adhesive
Oven (200°C/392°F for 30 minutes)
Q-tips or cotton swabs
Edding marker
Double sided adhesive tape

Step 2: Selection and Preparation of Soda Can

The basic part of the phone case is made from two soda cans. One can acts as the bottom part the second one is used as a lid. Therefore the two soda cans should be different in size, so the lid can be placed over the bottom part. However the gap between the two parts should not be too big because otherwise the lid will fall off. Two millimeters foam rubber that will be placed inside the lid will act as a fitting between the parts. So the selection of the correct size soda can plays a crucial role in this project.

In my part of the world three main soda can types are sold with the following diameters:

66 mm
58 mm
53 mm

For this project the two smaller ones (53 & 58mm diameter) are used. The bigger one is saved for a later step. Clean the emptied soda cans by rinsing twice with water and then let it dry.

Before you start to cut the soda cans apart you should consider if you want to remove the ink from the soda can surface. I have already posted an Instructable how to remove the ink from soda cans. You can find it under the following link: How to remove ink from soda cans.

Now we start a procedure to carefully cut off the upper and lower parts of the can. Pay attention to your fingers during this procedure, as aluminum edges can lead to heavy cuts. Use the utility knife to mark a groove around the can. Hold the knife on a piece of wood (wooden block 1) at a level plane and then rotate the can around. It is not necessary to cut through the aluminum. Apply some pressure with your fingernail near the groove to separate the top and the bottom part (see video: DIY phone case from soda cans). Repeat this step for both soda cans.

Step 3: Prepare the Spacers

In order to force the round shaped soda can pipes into the form required for our mobile phone case it is necessary to make some spacers. I found that the round shaped end pieces from wooden popsicle sticks are ideal to make the spacers. Only the length of the sticks has to be shortened with scissors to the desired length. I found that the following dimensions bend the aluminum can just nicely:

Lid part of phone case: 8.1 cm length
Bottom part of phone case: 7.3 cm length

To prepare the spacer for the lid, cut a popsicle stick after 6 cm from the end. Then combine two 6 cm popsicle sticks to an overall length of 8.1 cm and fix this first type of spacers with the stapler. The reason to take the stapler is that the spacer is exposed to high heat later in the project. Therefore hot glue is not a solution.

To prepare the spacer for the bottom part, cut a popsicle stick after 5 cm from the end. Then combine two 5 cm popsicle sticks to an overall length of 7.3 cm and fix this first type of spacers with the stapler.

If you have chosen to take soda cans with a different diameter than the ones mentioned in the parts list, you have to adjust the length of the spacers accordingly.

Prepare 4 spacers for the lid and 4 for the bottom part.

A second type of spacer is required to separate the spacers made from popsicle sticks in the can from each other. Separate a strip of aluminum (13.5 cm x 2.5 cm) from the third can and make a 1.3 cm slit about 2 cm from each end. Place both slits into each other to form a “fish-like” structure.

Step 4: Bend / Stretch Soda Can in Position Using Spacers

Start by adding wooden block 2 into the upright standing round soda can. Then add the popsicle spacer on top. Press the popsicle spacer against the wooden block 2 with the use of an Edding marker to bend/stretch the soda can in the shape of the phone case. Then add the “fish” type spacer on top. Continue layer by layer until you reach the top.

Step 5: Permanent Fixing of the Soda Can in the Shape of the Mobile Phone Case

Here comes the magic - place both stretched soda can parts in the oven for 30 minutes at 200°C (392°F) to permanently fix the cans in the desired shape.

What’s happening in the oven is the following: In order that the beverage inside the soda can does not come in contact with the aluminum, manufacturers of soda cans add special sealant glue on the inside. Since the soda can is produced in round shapes the later on added sealant glue holds the soda can in the round shape. In the oven you are heating the sealant glue past its glass transition temperature and allowing it to move. So the sealant glue is adapting to the new shape holding it in place. It is unlikely that the crystal structure of the metal is affected since you hardly reach the annealing temperature of aluminum in your oven.

After 30 minutes cool down the two parts under running tap water - remove all the spacers and you will see that the soda cans keep the new shape permanently.

Step 6: Prepare Lid

In order to shorten the lid to the desired length, place the Edding marker on wooden block 1 and mark a line around the soda can. Cut along the line with scissors.

Step 7: Bottom and Lid Closure Preparation

For the lid closure glue three pieces of foam rubber (30 mm x 90 mm x 2mm) over each other using contact adhesive. Place the 8.1 cm wooden spacer on top of the three pieces. Then cut along the wooden spacer with the utility knife so you obtain a closure in the exact same shape like your soda can lid.

Fix the closure into to the lid using adhesive glue.

Repeat this step for bottom par.

Step 8: Add Inner Protection

In order that the phone does not fall of the case and to protect it from scratches add two pieces of foam rubber on each side of the bottom part using double sided adhesive tape.

For the lid, use a single piece of foam rubber covering the entire inner surface of the can. Again fix it with double sided adhesive tape to the soda can inner wall.

On both parts (lid and bottom part) the foam rubber is overlapping the soda can acting as a fitting.

Now place your phone into the bottom part and close the lid. I hope that I have inspired you to repeat this project at home.