On 2021-01-22, NY wrote:
"alan_m" wrote in message
...
One other trick that can work if the screw is tight is to put the
screwdriver on the screw head and then give the other end of the screw
driver a whack with a hammer. Often then it starts to undo.

I've never found that works for me with seized screws, though I've often
tried it on the grounds that this time might be the exception! The usual
problem is not with screws that are painted over, but ones which have seized
into swollen wood or where the head is so rusted that it disintegrates and
becomes a round hole (if it was previously cross-head) when you apply enough
force on the screwdriver (by hand or by electric motor).

I sorted a stuck screw in an old wooden bed frame[1], by using a gas blow
torch to heat the screw. Had to do a load of protection to stop wood
damage. Let it cool and it came out quite easy. I assume the screw
expanded, then contracted slightly on cooling, just enough so the wood
was less tight. Luckily I only had to do it on one screw out of the
16 I had to remove.

[1] we had got a new mattress - alot deeper than the old one. The bed
frame needed adjusting down.