When the average Joe encounters a rusty bolt, nut, or screw, his first instinct is to reach for his favorite penetrating oil (PB Blaster, WD-40, etc.) and soak it. Others add heat to a nut to expand it and break loose the rust which often works wonders. Once it’s broken loose, though, there’s still a lot of rust and harsh metal-to-metal contact which can cause the bolt to break. An old trick I learned was to heat up the nut just as you usually would, but use a candle to melt wax on the threads; it will wick in between the nut and bolt threads. Once the nut cools and the wax dries, it will act as a lubricant, allowing the once-frozen nut to ease right off.
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