If you’re wondering how I made the 1mm ‘bullet’ style connectors for the modified HubSan X4 quadcopters, then it’s really easy to do. They’re made from 25 way D connectors that I bought on the high street from Maplin:
First, you need to separate the shells to get at the white bit inside which holds the pins. The only thing that holds the two shells together are the ‘riveted’ holes either side. When they’re made, the holes are punched through, and it’s only this that’s holding the two halves together. To get them apart you just have to hold the metal containing the holes on the left and right with pliers, working them back and forward and also twisting to make a slot separate which you can insert a screwdriver into. Then you can use the screwdriver to lever the two halves apart. Alternatively, just cut off the hole and you can open it up.
Then separate the two white inner parts with you fingers and all the pins (or sockets) fall out.
The gold connectors then form a male and female pair which you can solder wires on to and then add 1.5mm heat shrink over for insulation and mechanical strength. I was using 15mm long heat shrink for the pins (male) and 20mm long heat shrink for the sockets (female).
Let’s be fair though, I did make 80 of these connectors, and they did work very well when tested to extremes by a class of 13 year olds. The first time you push them together they are a bit tight, but once the heat shrink has stretched they’re easy to use. We had a class of 30 connecting quadcopter motors to flight controllers without any problems. I use this technique on any small connectors that I need because it’s cheap, quick and easy to source the parts on the high street.