I have a projector screen which weighs 26kg and I'm trying to fix it on to the wall. The screen has holes for two screws and I'm wondering what size screw I need to support that weight.
To complicate matters - I live in an old Victorian townhouse and upon drilling in to the walls it seems that they are made of pebbles and big pieces of flint. I've drilled 3 holes in a vertical line, about 2 inch below each other and it seems like the pebbles fell through from top to bottom, so I've filled the top two with polyfilla and stuck a yellow rawplug in the bottom and am waiting for it all to dry. I have some 2 inch screws - is this a recipe for disaster?
Below is one of the screws I have - I think I need bigger but can't make a hole big enough in the wall because of the flint all over the place. Is there anything else I can try?