Today was disappointing...
So, the JB Weld was hardened, and I threw the homemade "grenade" into the fire full of hope that I'd get a neighborhood awakening explosion.
It might have been.
But, the piece of steel I used to seal it off was a back-plate from a vehicle brake, which is designed to melt when the brakes overheat. So naturally, when I threw it in the fire, it melted, letting the prssure out, and I got nothing but a bunch of fire.
My final attempt, I've just re-filled it, this time with gasoline, and sealed it with the JB Weld and a piece of Stop sign, which I cut myself from the road.
Tomorrow, I'll try again.