Interesting rusted fastener removal technique

[maple_leaf_eh]

Originally Posted by tankbarrell

Exactly Martin! If there is a gap for the wax to get in, the thread is not rusted solid.

The wax wicks into whatever crevices exist, theoretically around and between the rust particles. The heat also disrupts that bond. by expansion. The demonstration's second message is that forcing a stuck nut or bolt will break it.