To make, use a Magnetic Glass Reed Switch 2 x 14 mm Normally Open, and a male to male or female to female wire. Cut it in half and soldier each one half to a side of the reed switch. Finally, embed the switch in the 3d printed part using hot glue, as seen in the pictures below. This part fits snugly into the rectangular opening on the washer (opening seen in picture) and fits in the Dryer too. (might need a little force to press it into the washer) Use at your own risk.