Old timers trick for stuck bolts

[LAB3]

This came across my feed, an old timers trick to remove a stuck stud with a crayon of all things!

https://youtube.com/shorts/Nvrs5G1YtNE?si=-5uCG4gxJ-R_3ZQR

[dpep]

Hard to believe that melted crayon would be superior to penetrating oil in this application. I am curious to know why from the physics/mechanical standpoint.

[rphillips]

Like he said, "hard to believe", but who knows?? First demo I saw of WD-40, bottle cap with WD-40 in it, hold a rusty bolt vertical and touch the bottom tip in the cap, and the liquid WD would run up the rusty threads just a gitt'in it... That too was "hard to believe"

[Grimly]

A wild-ass guess would be penetrating oil boils off too quickly*, whereas the wax melts and as it absorbs heat from the stud it causes the stud to shrink slightly, leaving a greasy coating on the threads.
Probably more to it than that, though.
*An effect I've seen for sure.

[dpep]

A wild-ass guess would be penetrating oil boils off too quickly*, ......

Makes sense. The crayon would allow heat and lubrication to be combined at a higher temperature.

[LAB3]

Down in the comments you'll see people suggesting bees wax and plain old everyday candles too.

[earlfor]

Thin high temp anti-seize with penetrating oil and drip onto a heated bolt. It will penetrate into the threads, but the antifreeze will never evaporate.