fatshark 18650 case switch

thingiverse

If you've got a spare Fatshark 18650 case, like maybe you blew the voltage display because you put the batteries in backwards, then you can mod it and have a switch and a digital voltmeter. *** NOTE: This does NOT protect against reverse polarity!!!! *** I use this on my Crossfire which is supposed to be protected against reverse polarity. I'd rather not find out. I removed the surface mount button that turns on the voltage meter and soldered 2 teeny wires (36g?). The hole for them is only 1mm diameter. I had these switches left over from my Fatshark goggle switch mod. Voltmeter is below. I included a template so you know where to drill on the case. To take the case apart, you have to remove the stickers and unscrew 3 screws and SLOWLY pry the black part off so the tabs release. There's a chance you may break the tabs. The voltmeter is soldered to the small button which is soldered to battery +. The XT30 power and balance lead power are soldered to the switch, so only the switch enables them. The voltmeter can be used without the switch. All grounds are soldered together. DO AT YOUR OWN RISK. Switches: https://www.amazon.com/gp/product/B07D7NCLKF/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 Voltmeter display: https://www.amazon.com/gp/product/B0761MG9NS/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 You'll need 2 M3 screws. Maybe 6-8mm long. I glued the display and switch in - trim the tabs off the volt display as well as the switch. Everything is quite tight.