Guys am I using Librem 5 as my only phone and have been since 2023, have surpassed 2 years. I do this with constant battery swapping all the time every day. I obliterated my Purism backplates, and I 3D printed more, and the 3D printed ones are a masterpiece and have solved all of my issues. To get the 3D print, I asked ChatGPT how to get them and it sent me to a company I had never heard of called Xometry. The guy from Xometry told me that their 3D printer did not have good enough tolerance to make a good backplate using the Purism STEP file that the Xometry guy said was made for a poured mold.
I told him to do it anyway. The first backplate they made for me almost fit, and I taped it the rest of the way on and used it that way for months. It was pretty OK and I liked it. Then, for fun (and for some friends) I ordered 3 more similar backplates. One of the 3 came out absolutely perfectly and fits perfectly without tape, and I’ve been using it ever since. I believe they said the material they suggested using was Nylon 11, but I’m not super familiar with 3D printing, I just went to a web portal at Xometry and submitted the open source STEP file from Purism.
After obtaining these 3D printed ones I have never used the Purism poured mold backplates and never gone back. The 3D prints are that much better, I think they will not tear apart based on my experience popping it off and on every day.
Edit: If I drop my phone, and it bounces from a lot of force, often the 3D printed backplate will fly off from the force. It’s possible that the Purism poured mold backplate has a slightly tighter fit. Maybe that one wouldn’t fly off. But for me this is OK. I like to think maybe it transfers the energy of the fall into the backplate and deals less damage to the device itself… or something. (My picture attached in this thread is a photo of the 3D printed backplate on a device that has broken somewhat from falling repeatedly. I doubt that the screen breaking has anything to do with the custom backplate, but admittedly my previous idea that the backplate is saving the phone when I drop it might be dubious.)
Edit2: When I say “I taped it” this might not be what you think. Rather than using the adhesive of the tape to connect the backplate to the device, I used the adhesive to hold the tape onto the backplate, and put the tape onto the tabs to make larger tabs to create a tighter fit. That way, frequently attaching and detaching the back was possible while still having a tigther fit.
Edit3: Above is a photo taken - while holding my phone with the “perfect backplate” - of one of the other backplates that did not happen to fit perfectly, and thus has tape applied.