Total newbie to drilling. Am trying to install roller blinds to the top of my window recess. I am aware there is metal behind plasterboard which is 2cm thick. The plug and screw given for the blind is 3cm and 2.5cm long. I have punched through the metal with a 3.5mm metal drill but this isn’t wide enough for the plug. I’ve then tried a 5mm metal drill bit but this isn’t going through and the plasterboard hole is now massive.
So the plug won’t fit the 3.5mm hole in the metal but the plasterboard hole is almost 6mm and the plug is 5mm wide. What am I doing wrong apart from trying to save money. #diy source