Post AShGyB8T04fphSpUtk by brad@weeaboo.space
 (DIR) More posts by brad@weeaboo.space
 (DIR) Post #AShGJXz98nTMh65z96 by brad@weeaboo.space
       2023-02-15T07:36:59.414055Z
       
       0 likes, 0 repeats
       
       I believe I've figured out the mystery of all the bent and broken switch pins. There's an internal cable (kinda dumb but the build guide I originally used was using it so I copied it) which is between the PCB and case, applying a bit of pressure on the left side where the microcontroller is (the cable is longer than it needs to be so the slack is kinda bunched up and doesn't sit flush). The switches on the left side generally never gave me much trouble. It was the ones on the right side of the board that gave me trouble. So what I think was happening is the left side of the board was pushed in more firmly and "higher up" than the right side, which sagged a bit, creating a weird angle and making it harder to insert something straight down when the board wasn't level. My solution for now was to stick a bit of plastic in there on the right side under the PCB (a choc keycap that came out a bit ugly that I had put in my scrap bin) to apply pressure more evenly. I put a bit of mounting putty on it so that it sticks to the bottom cover when I take it out also. After doing this I was able to put in 6 switches I'd been struggling with for days without bending a single one of them. They all just worked on the first try.The only remaining problem I have with this particular board is that the center button is not actuating reliably. I reflowed the solder on that hotswap socket and it didn't seem to help. It's like it misses presses and sometimes you have to press very hard to make it work at all. I've changed the switch out and it doesn't help. Also, the pins weren't bent at all. It's very odd. Maybe I need more things sandwiched around there, maybe even right under the hotswap socket, in order to get more consistent results.I would say I've had issues both with bent pins and with some buttons being inconsistent on all 5 of these I've built, but to varying degrees. So it's possibly my prints aren't all coming out quite the same, or I bent the cable out of the way a bit differently for some.If I ever built another one of these from scratch, I think I'm gonna skip the internal cable. As an alternative you can solder the microcontroller right to the board, no pin headers, and then there are some additional contacts you can solder for the USB routing to work. (It all seems to be in place because the Pi Pico has a microUSB B connector and they want a USB-C connector on the outside of the case for connecting to, so you need to make that connection internally somehow)
       
 (DIR) Post #AShGyB8T04fphSpUtk by brad@weeaboo.space
       2023-02-15T07:44:18.152205Z
       
       0 likes, 0 repeats
       
       I don't have any screws connecting the PCB to the top of the case. I'm not sure if I'm supposed to. I have threaded inserts I melted in for the external case screws, and then the pressure of being sealed kinda pushes everything together, but maybe there's more I could do to keep things tightly together. The Pico is on the top side of the PCB, though, so I really don't like things making it even harder to access than it already is in case of an emergency (bad firmware, having to reach the actual BOOTSEL button to reflash). As it is, you have to remove every switch and pull out the PCB to get at the top side and hit that button. With hotswaps that's annoying, but imagine if you'd soldered in your switches... Yikes. I've been thinking if you could make a pin hole in the top to poke a paper clip through and hit the button, that might work. Otherwise some sort of window/removable cover in the case design above the Pico could work. With the PCB design as it is, putting the Pico on the bottom would have all the wrong things making contact (left becomes right), otherwise that would work too.