11mm is almost exactly 7/16 inch.
To determine the correct drill bit size for a project, you should refer to the instructions or specifications provided for the project. Additionally, you can use a drill bit sizing chart or measure the diameter of the screws or fasteners you will be using to select the appropriate drill bit size.
For creating a pilot hole, use a drill bit that is slightly smaller in diameter than the screw you plan to use.
For a 1/4 screw, you should use a drill bit that is slightly smaller in diameter than the screw itself, typically a 3/16 drill bit. This will ensure a secure fit for the screw.
The size of the drill bit you should use for your project depends on the size of the hole you need to drill. Check the project specifications or use a drill bit sizing guide to determine the appropriate size for the job.
I drill a pilot hole the size of the 'barrel' of the screw. -I always use a combination drill bit for sinking screwheads. The first part of the bit is the diameter of the 'barrel' of the screw and the step, one inch higher is the size of that screw's head. (The barrel is the diameter inside threads) -I have a set of these drill bits for #6, #8, and #10 screws and they are great.
For drilling into wood, it is recommended to use a twist drill bit. These bits have a sharp point and spiral grooves that help to remove wood chips as you drill. Make sure to choose a bit size that matches the diameter of the hole you need to create.
For a 1/2 inch lag bolt, you should use a drill bit that is slightly smaller in diameter, typically a 7/16 inch drill bit. This allows for a snug fit and proper anchoring of the bolt.
The recommended size for a drill bit to use with a 5.5mm screw is typically 5mm.
A 3/16 drill bit.
For a 1/4 bolt, you should use a drill bit that is slightly smaller in diameter than the bolt itself. In this case, a 7/32 drill bit would be a good choice for drilling a hole for a 1/4 bolt.
For a 6 screw, you should use a drill bit that is 7/64 inches in size.
The recommended size of the drill bit for a 7/16 inch hole is a 7/16 inch drill bit.