Screw the nut 

Glaswegian slang meaning “be careful”, “pay attention” or “stop messing about” depending on the situation. Your “nut” is your head, or your brain, to be more precise!

“Screw the nut, ya dafty!”
…means “stop messing about, you silly person!”

Screw the nut by Terrysuki July 25, 2022

screw the nut 

British army slang for work harder you bastards.
Used mainly by NCOs at an attempt to get soldiers to work harder or put in a better effort.
After a fair amount of time in the services a soldier will learn that this phrase really means, make it look like im working harder.

Corporal} boys screw the nut else this will get a bit cheeky....cunts.

screw the nut by banta87 October 22, 2010