The goal is to mount a rail for hanging coats. I have the sizes and I can calculate the required pull-weight, but I don't know how much the plugs can withstand before being pulled out of the wall (the force applied is axial to the plug).
The plugs are 31 mm (1.25”) long, diameter 5 mm (3/16”) (the same of the hole I made). I used a screw 40 mm (1.5”) long with diameter 3,5 mm (1/8” or #6) as recommended by the manufacturer ("3-4 mm"). The hole was well cleaned from the dust before applying the plug.
How much pulling force can these plug withstand? should I use longer plugs and screws? like 50 mm (2”) long, same 5 mm (3/16”) diameter.
The geometry. As you can see, the lower plugs (there are multiple ones) act as the fulcrum of a lever, resulting in a pulling force applied to the upper plugs. This is why I need to know only the force to pull out the plugs, not the force parallel to the wall.