This is general purpose screw switch made for 150g combat robots. This is low cost low current alternative for fingertech switch. It weights 2.5g with short wires and mounting screws included. No supports needed for this print.

All you need it:

• 2x M3 square nuts (5.5x2mm)
• 1x M3x6 screw (don't use stainless steel, use aluminium or carbon steel screw)
• 2x M2x8 mounting screws
• a metal file
• metal pliers
• soldering flux
• a soldering iron
• 16-20 AWG silicon wire so something similar depending your use
• Power drill and M3 drill bit
• Regular food grade citric acid, 30g bag is enough for 100 nuts.
• Isopropyl alcohol

Steps:

• Use citric acid to remove the zinc coating from the nuts. Use spoon to mix it in a glass mug. Wait until the nuts are more silvery than brown.
• Remove the threads of one of the nuts with a M3 drill bit. This will be the upper side or screw side nut which contacts the screw head.
• Use a metal file to roughen one of the sides of each nut to make better soldering surface.
• Apply soldering flux to the filed side of each nut.
• Use Isopropyl alcohol to clean the dust off before soldering. Solder wires to square nuts (I used 20AWG cable)
• Press nuts into the print. Make sure the drilled nut is on the screw head side. File the corners of the nut if print tolerances are too tight.
• Insert M3x6 screw to test continuity of the switch.
• (optional) Apply conformal coating or silicone based glue over the solder joints.

The hole pattern is 8.5mm with 1.6mm mounting holes for M2 screws. Depending on what material did you use you might need to drill out the holes or use M2 nuts. I used nylon which is nice material to thread screws into. If you have problems printing I included a beefier model which has more material around the edges.