Penetrants

[Maysik]

Heat the threaded area up and then jam a candle on it. The wax makes into the threads and acts as a lubricant. An old bloke told me about this when I was an apprentice in the early 80's. His reasoning was any liquid penetrant burns off to quickly. Wax stays put.

x 2 for the candle wax, I've heard it works well.