Help finding a heat resistant, non-conductive, and pressure tolerant material

[jetpackjbd]

Requirements:

• >500°C heat resistance
• Nonconductive
• Able to seal, or non-porous if needed
• Won’t dissolve in water when cured
• Consumer-accessible; no materials I need to buy in bulk for a factory

For context; I’m working on developing a concept for a new engine. I need something similar to a glow plug that can go on the end of a brass cylinder 6mm wide inside. No glow plugs I’ve found are this small, and I also need it to be heated constantly.

So far, I’ve tried putting resistive wire into clay on the end of the cylinder, however it seems to crumble too easily and not seal well. Epoxy would be perfect, but it can’t handle high temperatures. Silicone may work but it’s flammable, it’s also hard to get to stay in place in my application.

Also, I’m doing this all with basic tools. My methods of machining are a $40 Amazon mini wood lathe and a pair of calipers. I can’t use anything like steel.

Any eng tips are appreciated!

 

[IRstuff]

Spark plugs use ceramic bodies

 

[jetpackjbd]

Spark plugs use ceramic bodies

Thought about that, that’s what I was trying with clay. Might need to make some proper ceramic to test it, a bit difficult to do at home though.