Smart phones are ubiquitous. It is rare to find anyone who doesn’t have a smart phone of some form or another. Android and iOS Apple devices seem to dominate, but changes are always happening in the fast paced market for personal electronics.

FDM printing of smart phone and tablet cases is a great choice. You can print with standard plastic or use rubber-like TPU filament to provide a flexible case. The advantage is that you can customize the case and change any aspects you like in something like TinkerCad.Com and print in whatever color your filament comes in.
DLP resin printers are capable of printing cases, but the resin, once it’s UV cured, is very brittle and inflexible. That rather defeats the primary purpose of a phone case – protection. It could, however, provide you with a very intricate and interesting design if protection isn’t your required attribute. The higher resolution could allow you to create some really neat designs.
Downloading Phone Case Designs
Any of the usual suspects in 3d designs for download will have case designs in STL format. I tend to use Thingiverse.Com and Yeggi.Com (which tends to point to things on Thingiverse.Com anyway!) I have an older iPhone 7 Plus. I simply put “iPhone 7 Plus” into the search area, and this is the design that I chose:
The nice part of downloading a phone case design is that it’s likely to fit your phone. You don’t have to do the measurements for the case size, hole locations, or corners. It means it will fit will and will protect your phone in case of a drop.
Modifying and Customizing Phone Case Designs
Once you’ve chosen a design, you can modify it to customize it to your liking. I intentionally chose a rather dull design for a phone case, so that I could have a good “blank canvas” to add some cutout lettering.
Download the STL file from Thingiverse.Com or where ever you’ve found it. To modify it, go to https://www.tinkercad.com/ and create an account. It’s free and secure. Follow the steps below to create what I created!
- Click the “Create new design” button in the upper left. This will launch the design area of the TinkerCad application. You’ll see lots of “primitives”, or shapes that you can pull in and design with.
- Above that section, on the right, is a gray “Import” button. Click it, then drag the .STL file that you’ve downloaded to this screen. In a few seconds, you’ll see it rendered on the design plane.

- Left-clicking on the object and dragging it moves it around on the Workplane.
- Using the wheel on your mouse will zoom in and out for your view. That’s handy!
- Control-Z is your friend. It’s the undo command. Use it if something doesn’t go your way and you want to get back to the last step. It’ll let you go back a few steps, if you like. Once you go back in time, there’s no way to go forward again, except to redo the work.
- Right-clicking on the object will change the view but leave the object where it is. Use this to move around the object to see its front, back and sides. I’ll be doing my work on the back (the side that will be up against the back of the phone).

- If you click on the object, you’ll see some white corner boxes appear (and a few others). You don’t want to mess with these at this point, as they’ll resize the object – defeating the purpose of downloading a presized phone case.
- For my design, I’m going to cut out a design below the Apple Logo hole. I do this by selecting the text tool and dragging it over to the phone case. The 3d rendered word “TEXT” will come over. That’s okay, we’ll edit this.
- Clicking on the word TEXT will bring up an information pane. It’s here that I’ll modify the text.

- Now, the text is far too big. Now, I’ll click on the text object, and it should have the four corners highlighted with white boxes. I select and hold down the mouse on one of the corners, and with the Shift key depressed, I’ll slide the mouse around. You’ll see that you can make the object larger or smaller. I want it smaller. I make it so that it’ll fit in the space. I then let go of the mouse, and reselect the object. I can now drag it to be centered and where I want it.
- I did the whole thing again with my second line of text.

- We’re looking at the inside of the case, so we’ll want to mirror our text to read backwards (so it reads forwards on the outer side of the case). To accomplish this, I grab the corner box again, and with the Shift key down again, I drag to the left, and the text will eventually reverse. I have to resize again and drag it back to the center, like in Step 10. I do this for both text lines.
- Now here’s the tricky part. Click on the first text object, and find the center white box. Select it and drag it up. It’ll make the text really tall.
- Change your view so that you’re looking at the edge of the case. To do this, click into an unused area and right click, then drag to change the camera view.
- Now, when you select one of the text objects, you’ll be able to see the black triangle button hiding above the text. Use this to move the text object down. Move it down so that it sticks out above and below the phone case.

- So now you’ve got your text jammed through the object. It looks sort of silly, but the “ah hah!” moment is coming. Select the two text objects (you can select the first object, hold down the shift button, and select the second object – you’ll how have both selected). See the red circle labeled “Solid” and the gray striped circle labeled “Hole”? Select “Hole”.
- Something happened, but you can still see the tall text extending through the case, but it’s an outline.

- Select the two text objects and the case (again, hold down the Shift key to select multiple objects). Group these three objects (it’s the button that looks like a square and a circle merged, to the left of the Import button that we used at the start.

- Now that you’ve got a group, it still looks the same. This surprised me when I first did this. I moved around the view (by right-clicking into blank space and moving around), and suddenly, the tall text was gone, and only one object remained, my phone case with the text cut out! It worked!

- The last step is to use the Export button and download the STL file for your new, modified phone case. You can use this to print!
Print Your Phone Case
As I said above, it’s better to print a phone case using a flexible material on an FDM filament printer. At least that’s my preference. I recommend TPU filament (or thermoplastic polyurethane). Here’s a link to an Amazon.Com offering: https://amzn.to/2JZsNpk
TPU filament comes in multiple colors. I like the truck tire feel, so I print in black. Choose something more to your liking when you order your TPU filament!
Printing on a 3d printer is no different than printing with standard PLA filament, except the temperatures will change. Try printing at 230°C and if you have a heated bed, heat it to no higher than 60°C. I would start at 55°C and see how it goes.
You shouldn’t need any supports, so this print should be rather quick. For most printers, you can complete the print in around an hour. Remove from the build plate once it’s done. Try it on your phone!
Services To Print Phone Case Designs
If you’re not comfortable with printing your own design, you can upload STL files to Shapeways.Com. Choose your material, select your shipping and have them print it for you.
There are other 3d online design tools to make some cool patterns in the plastic. Check out http://www.3dphonecase.com/. I’m a little worried that they don’t have iPhone 7 Plus, or anything newer, and they don’t have an SSL certificate for their site. For all I know, this site is defunct and out of business. That’s okay, as I’d prefer to print my own design, and their prices are rather high. They’re in Europe, so the shipping is likely high, too.
Don’t be afraid to try printing your own case. It’s not a hard project, and you can modify and customize your design. Save your phone from drops with something unique and stylish!
Related Questions
How long does it take to 3d print a phone case?
If you’re printing on a home FDM filament printer, your print, if it prints flat on the bed, will take less than an hour, and in some cases as fast as 30 minutes. Other technologies, like DLP resin 3d printers, will be similar, unless the print is suspended on supports, raising the height of the overall build, making it slower.
How fast can you 3d print?
3d printing with FDM filament printers is variable, based on the speed that the print head moves, and the size of the model being printed. If you’re printing a one inch cube, it’ll print much faster than a six inch cube, for example. For DLP resin printers, each layer is printed in a single shot. If you’re printing at 50 microns in the z-axis, you can print 30-40mm per hour. If you’re printing at 25 microns, your time to print is nearly doubled.