Project Farm wanted to see if candle wax could be used as a penetrating lubricant to loosen rusty nuts, so he set up a rigorous test to find out. His conclusion – candle wax applied to a hot nut doesn't help loosen it. It just won't penetrate onto the bolt.
He also tried special penetrating fluid designed to make it easier to loosen rusty nuts, called Seafoam Deep Creep, which really does do the job.