Finally got my own RP2350 boards back from assembly and they just work

Did something similar last year with an RP2040 board, though I went with a panel of four and soldered the parts myself while watching telly. The one thing I got wrong on rev one was the debug connector position. I put it too close to the mounting hole and my probe cable would only fit if the board hung off the edge of the box. Moved it on rev two and life got much easier. Worth measuring your actual cable before you lock in the layout. On the battery side, since you mentioned that for the next revision, I used a pair of solder pads for a JST lead rather than a holder soldered direct. Gives you the option of different packs later and makes it simple to disconnect when the board is on the bench.

My first assembly came back with one board that had a bridge under a chip I couldn't see without a loupe. The assembler replaced it no fuss, but since then I always ask for a photo of the panel before they ship. Costs nothing and it caught a bent pin on my last order. Also, don't be tempted to shrink the boot button down to a tiny SMD one just to save space. I did that and regretted it within a week. A full size button you can hit with a fingertip is one of those small things that keeps paying off.

I went a slightly diferent way with mine and put a plain row of pads on the underside instead of a socket. I use a Tag-Connect pogo lead with it, so there is nothing sticking off the edge of the board to catch on things, and the same pad pattern has carried over through three revisions now. The lead cost me about twenty quid and it has paid for itself many times over. The downside is the first press sometimes takes a wobble to make contact, so a socket is nicer if you are in and out of the debugger all day.

On the sensor plug, the one thing I would tell anyone copying that idea is to check the voltage before plugging things in. Mine runs at 3.3V and an old module I had from a weather station project wanted 5V on the same pinout. It did not end well for that module. A jumper to select the rail would be my addition for the next revision, next to the battery pad.

Also give some thought to how many of those plugs you want. I put one on mine and immediatly wished I had two, because chaining the display and the sensor meant I was back to soldering leads after all.

I've been cobbling togehter stuff on those little breadboard strips for a while and the wires going everywhere is half my problem, so reading this makes me want to try the same thing. The bit that confuses me is how you actually go from a drawing on your computer to a real board in the post. What program did you use to draw it up, and did you need to know a lot beforehand or can you pick it up as you go? Also curious roughly what a small run like that set you back, ballparks are fine.

Nice one. What did the whole run end up costing you through the assembler, roughly? I keep pricing up getting mine done properly and it always works out cheaper to hand solder, but my time isn't free either. Also curious how many boards you ordered, since I'd guess the minimum order forced more on you than you'll ever use. That's always my problem, I've still got a drawer full of spares from projects I finished ages ago.

The Qwiic socket is the bit I'd flag for rev two. Mine ended up flush against a big capacitor at the board edge and the plug wouldn't seat flat because the cable had nowhere to bend. Shifted everything on the next layout so there's a few millimetres of clear space past the socket and the cables clip in clean now.

Also found it handy to put a second one on the opposite edge, daisy chaining two sensors without a splitter lead.