Overview

I decided to create a case for my Pixel 9A from scratch, partly because I wasn't completely satisfied with any of the other options I could find and partly just because I wanted to model something.

This two-piece hard case was modelled from scratch in OnShape, and developed over several iterations for fitment and ease of attachment/removal. It has since seen several weeks of real-world use. Both the case and insert are designed to be printed in a hard material such as PLA or PETG; I haven't yet tested it with TPU and don't know how well it would fare, although I have included a solid, one-piece version of the case designed for flexible materials should anyone be interested (although again, I'd like to stress - untested). Even when printed with rigid PLA+, the rear pattern cutouts and side cutouts for the phone's buttons, USB-C port and speakers provide sufficient flexibility that it can easily be snapped onto and removed from your phone.

I've also included STEP files of a template case, featuring a blank rear cutout and blank insert, should anyone wish to remix it with a design of their own for the back. Sometime soon I'm also planning to prototype a variant with space for a credit card or two between the pattern insert and the phone.

BoM/Hardware

This design requires no non-printed hardware to produce. At least two colours of filament are recommended for aesthetics, but this will not affect functionality at all.

Assembly Instructions

Print the case and the insert using the recommended settings below. Clean up any stringing on either piece and verify tolerances/fitment between them - the insert should simply press-fit into the cutouts in the case. If it doesn't, you may need to trim away any extrusion artifacts on the top layer of the insert with a hobby knife, although I didn't find this to be an issue with a properly tuned MK3S+. Snap the case onto your phone and you're done.

Print Settings

Case

The case has been tested with both 0.4 mm and 0.6 mm nozzles; both will work fine. Make sure your overhangs/cooling are good and that your first layer elephant's foot compensation is well-tuned.

Insert

The insert has also been tested with both 0.4 mm and 0.6 mm nozzles. 0.6 mm will work in a pinch, but I strongly recommend a 0.4 mm nozzle, unless you're confident that your Linear/Pressure Advance and retraction settings are tuned absolutely perfectly - and even then you may lose some detail in small features.