Why the smartest way to loosen screws is from the head.
Everyone knows that you can use heat – and of course induction! – is something everyone knows. Such cases are annoying enough in the workshop, but can be dealt with using a flame if necessary. But what if only the head of the screw is visible? You can forget that with a flame, as this heats up the screw and its surroundings. And relatively slowly at that.
The big difference with induction: Due to the effective depth of more than 15 mm and the rapid drop in effectiveness at material boundaries, it is possible to heat only the screw very quickly. It wants to expand, but cannot. In this way, any deposits and rust bridges in the space between the threads are simply crushed.
When the screw has cooled down again, it runs instead of tearing off.
Many thanks at this point to Peter Buck, who made this nifty animation in no time at all!