Blown Frost Plug

[greeno]

Yeah, I dimpled it and used aircraft permatex. Gonna pressure test the system to 7 psi before reassembling this time.

[just me]

You "dimple" the plug to remove it. To seat one, you need to hit it with a flat face tool that is at least 80% the diameter of the plug. That will expand the circumference. Then, a hit in the center with a peen will shrink the circumference for removal.