These screw switches are designed to act as a robust switch mechanism for power management for rocket electronics. You can wire these inline to the positive power line/wiring and then tightening the screw switch will securely power on your rocket electronics. Simple to do once your rocket is on the launch rail. They stand up to high g launches and violent flight profiles and of course this means they could be used in any power system prone that needs this ruggedness, small combat robots for example! When the screw switch is tightened the two through hole solder pads are connected so you can essentially wire this into a cut in the positive wire in your system.

These are the MK2 version, the earlier version https://www.tindie.com/products/concreted0g/rocketry-screw-switches/ worked extremely well but I CNC routed them in my lab and I never could find the time to produce more. I decided to re-spin the design so that I could have the base board made by a PCB fabricator. This means they are less hassle to make, and with the time and hassle saved I can sell them a little cheaper. Similar to the original version these are sold in two packs so if you're running a high power rocket with a main and a redundant spare avionics system then you can switch both independently!

Designed for use in mid or high power rocketry I made these switches as I was concerned with failure rates in cheap keyed rotary switches. I’d had success using 3.5mm stereo sockets and jacks as “remove before flight switches” but with increasing G forces I wondered at what point the metal plates in the stereo socket would open. The screw switch is a better solution and has now flown in numerous mid and high power rockets, including some violent flights with non optimal deployment! (hey it happens to all of us!) I’ve suffered no loss of continuity in my testing, flying with logging altimeters. After the PCB's arrive I press fit the PEM insert nut into the PCB using my 1.5 ton capable arbour press, so they are very firmly inserted! You might notice that the inserted PEM nut isn't completely central to the hole but that variation is difficult to get rid of with the arbour press and does not effect the functionality. Each switch is checked and inspected before packaging up.

The PEM nut on the bolt is secured with a small dot of loctite but can be removed and you can replace the M2 bolt with a longer bolt if required (some people find this useful to have a longer bolt with the pad threadlocked in place at the lower end of the bolt with the bolt head standing off closer to the airframe access hole/port). I’ve flown these mainly with the switch bolt tightened into the on position with a small screwdriver and have not used any threadlocker on the switch bolt threads, you might feel you want to add a small dot to the switch bolt threads. The screw switches haven’t failed for me either way so the choice is yours. The two M2 mount holes are 11mm apart about their centres and depending on how you mount them you may need to create a clearance hole for the centre inserted PEM nut and the bolt.