The screw is one of the most popular hardware, often used for repairs and various designs, is beneficial in that it reduces costs in time and labor.
Screws are made of high carbon steel with oxidized finish. Available in various lengths, diameters and may have different thread pitch. Depending on the use of metal screws come in a variety of types. For easy screwing them usually in the fastened parts pre-drilled holes. But these holes needs to be drilled taking into account the thickness of metal and type of hardware. For example, screws with pressshayboy with a drill on the end of the contact metal structures, sheets up to 2 mm can be mounted without drilling holes.
Self-tapping screws with pressshayboy, sharp lugs and attached metal products to other materials. If the thickness of sheet steel up to 0.9 mm without pre-drilling.

Black screws on the metal plate attached to the wooden base without drilling, and when sheet thickness more than 2 mm, it is already necessary to drill the hole.
A hole is drilled in two work pieces that are pre-installed in the desired position. Drill bit for holes for the screws you want to apply universal metal.
The upper part is drilled a larger diameter than the screw, the clamping effect. The bottom surface is drilled with a diameter equal to the diameter of the screw minus two to the height of the thread (the distance from the top of the thread to the base of the profile, measured perpendicular to the axis of the screw).

The diameter of the screw is determined by the marking in the store or caliper is measured independently.
With increase in the thickness of the metal and increases the diameter of the drill. For example, the self-pressshayboy and sharp tip and with the tip of a drill bit increases with the thickness of sheet 0.5 mm leads and an increase in drill diameter 0.1 mm.
Black screws with a sharp tip by increasing the metal thickness of 0.5 mm should increase the drill diameter by 0.2 mm. hole Depth should be slightly greater than the length of the screw.
After the hole is ready, it must be cleaned and lubricated. Screw the screws you with a screwdriver with the appropriate head or screwdriver.