soldering teensy wire to a chunk of copper

[kteepa]

I'm hoping to use some CNC'd copper (or aluminum, but I assume that will be even harder) as the conductor for a proximity sensor that is being read by touchRead on a teensy 3.2. How do you suggest I solder 22awg stranded tinned copper wire to this CNC'd copper? It's a highly conductive CNC'd copper meant for electronics.

type of solder/flux/heat source? been researching a ton online with very conflicting results.

My current fallback plan is silver epoxy.

 

[MarkT]

Standard electronics solder (rosin cored) and a temperature controlled soldering iron, like any other solder joint.
All copper-rich alloys will work for electronics, I think you mean its a special alloy designed to be machinable (pure
copper is not machinable, it clags up horribly).

Aluminium does not solder at all, the thermodynamics are wrong.