I had heard that O'donell's may start producing glow plugs again, but it looks like their website is down. I hope this is not bad news. Anyone know what is going on?
Jeff
Looks like Castle came out with the smaller version of the Hydra XLX 2
https://www.castlecreations.com/en/marine/hydra-x-8s-33-6v-esc-8a-peak-bec-010-0175-00
Here is a magnetic switch.
https://www.featherweightaltimeters.com/av-bay-components.html
I've used them on a few different rockets. Work very well but orientation matters when installing them. They also work through carbon fiber. But remember that even if the device it is controlling power...