During the pandemic, I had a small fixation with computer mice, and since I was playing a lot of video games, I was especially fixated on lightweight gaming mice. I ended up trying out and collecting a bunch of mice during that time, but after starting school, I had a lot less time for video games, so my fixation for computer mice died down.

After coming to the US for school, though, I brought a couple of my mice with me, including the Logitech G305. I was never a big fan of it because of its awkward wide shape, heavy weight, and because it used a AA battery. The G305 is very popular within the mouse modding community and thus there is a lot of support and models for modifications to the shell, battery adapters, and rechargeable battery swaps; I had attempted a shell swap with some 3D printed parts years ago with little success, and so I left mine stock after that.

After graduating, I found myself with a lot of free time, and I remembered I had a couple of leftover Li-Po batteries from the Crawling Caterpillar and finally decided it was time to make the custom G305 happen.

I found this model by Wiyum on Thingiverse and printed it to give it a try.

For the electronics side, I got a cheap USB-C PD trigger board and connected it to the battery charger board for the Li-Po battery, and swapped out the old AA battery setup.

The online model did not account for a Li-Po battery swap, and the USB-C PD trigger board was a little bigger than I anticipated, so I had to make some hardware changes to the shell after printing, and the charging and PD boards and battery inside are held by uhu tac instead of being properly mounted.

However, despite the hardware limitations, the mouse works perfectly! The shape is much more comfortable (for my hands at least), and it is now only 84 grams from the original 99 grams (per Logitech data); and this weight is including around 5-8 grams of uhu tac that should become 2-3 grams proper mounting structures when I redesign and print the v2 shell.

The battery drains really pretty quickly, and there is some pretty noticeable coil whine when the mouse is on, but I believe both of these issues are due to the step-up converter that is integrated into the Li-Po battery charger 5V output (we chose this because it was what we needed for the caterpillar project), however, the mouse can run with the usual 3.7V from the Li-Po battery. For the next version, I plan to replace or modify the charging board to avoid the inefficiencies of the step-up converter. I will also move the USB-C port to the front so I can more comfortably use the mouse while charging 😄