Remove a rusted bolt with a crayon

[SS427]

I have had many instances where I could not remove the heater hose nipple from an aluminum manifold or the cast iron water pump. Any more I do not even try without first applying heat and a paraffin candle wax. Trust me, it really works. The key is just like soldering, get it just hot enough for the wax to wick down the threads. It works about 95% of the time for me. I also made a tool to use on the slotted nipples using an old socket and that greatly increased my results.