Really tiny connectors!

I was feeling pretty smug about having thought to include a wiring channel along the top of the boiler to make room for marker and headlight wires. Then I started to think about how to get the electricity from the decoder to those wires, and how to make it so that everything can come apart, as it will surely need to do, and I began to panic. There simply isn’t much room inside 622 for anything! Even USB-C connectors are giant when you hold them up to the cavity they would have to fit in.

Fortunately, I am not alone, and after a week of scratching around, I found Tony’s Train Exchange has some connectors that fit six wires into about 6 mm. They looked like they were made out of headers, and so, I got on the Mouser and Digi-key websites, and eventually found some 1 mm pitch headers by Sullins. I drew them up in OnShape and designed a little cavity for them in the boiler wagon top, and it all seems to fit.

Now, once the motor is filling up most of that same cavity, maneuvering wires and connectors will be about as awkward as changing in a crowded locker room. So, this design may not work. However, the really tiny connectors feel likely to reveal a path once I have them in hand.