Step by Step instructions How to screw in wood and plastic Different screw heads As well as the simple slotted screw head, there are three different types of screw heads into which the screwdriver or bit fits: Phillips (PH), Pozidriv (PZ) and Torx (TX). Pozidriv (PZ) is the most widely used. PZ screw heads have extra slots compared with the PH. The corresponding (PZ) screwdriver bit has straight internal edges with parallel ribs between them that fit into the slots in the screw head. The Pozidriv screwdriver or bit is recognizable by the rounded tip. This allows it to enter the screw head more deeply, giving a better grip. Phillips screwdrivers and bits have a pointed tip with ovalshaped ribs. (See also the step-by-step instructions Hand tools and a tool board ; step 9)
The right screw for the right job 1. Wood screws - Head: countersunk-dome - Fitting: PZ/PH/Torx - Used for: general woodworking 2. Sheet-metal screw - Head: cylindrical-oval-round - Fitting: slot - Used for: fixing thin sheet metal or plastic. These screws are self-tapping 3. Dowel screw (double-ended screw) - Head: wood thread (metric) - Fitting: double-ended screw - Used for: invisible joints between wood panels, beams etc. 4. Wood bolt or coach screw - Head: hex head - Fitting: wrench or socket - Used for: fixing heavy beams or other structural wooden joints 5. Mirror screw - Head: countersunk - Fitting: PZ - User for: mounting mirrors and bathroom accessories. The screw head is concealed by a chromed or plastic caps 6. Wood screw - Head: round - Fitting: slot - Used for: general woodworking 7. Wood screw
Fitting screw This type of screw is used for fitting strap hinges (piano hinges) and window hinges. It has a smaller head diameter than normal, so the head is countersunk unobtrusively in the hinge. Available from 16 to 30 mm, usually with PZ fitting. MDF board screw MDF board screws are ideal for use in MDF panels in home interiors and furniture. The screw head can be countersunk quickly and easily. You can screw close to the edge without splitting the material, and there s no need for predrilling. MDF screws have a special thread pattern, and are available from 40 to 50 mm, usually with TX fitting. Floor screw Floor screws are ideal for use in solid wood floors. The screw can be countersunk entirely in the floor thanks to the conical, smaller-diameter head. Predrilling is not necessary; floor screws do not split the wood. Available from 35 to 55 mm, usually with TX fitting. Particle board screw Particle board screws are for joining board panels, for example in carports, balconies and other supporting structures. They are also used for plinths, hardware fittings and finishing laths. These screws are available with countersunk, cylindrical and oval heads. Available from 35 to 200 mm, usually with PZ fitting. Plasterboard screw Plasterboard screws are suitable for fixing plasterboard on wooden supporting structures. They have a trumpet-shaped head and a coarse screw thread. These screws allow fast, strong fixing. Predrilling is not necessary up to 2 mm thickness. Plasterboard screws are hardened and have a protective plating. Available in lengths from 25 to 90 mm, usually with PH fitting. Stainless steel screws Stainless steel screws are ideal for use outdoors or in damp environments. These screws are available with countersunk, cylindrical or oval heads, and are intended for wood to wood joints such as in carports, balconies and other supporting structures. Available in lengths from 25 to 120 mm, usually with TX fitting.
Construction screws Construction screws are easy to fit thanks to the shorter screw thread length. These screws are ideal for wooden structures such as timber frames and houses, carports, home extensions and play areas. It s easy to countersink these screws thanks to the cutting ribs under the head. Predrilling is not necessary. These screws are available with countersunk head and low round head with flange. The length varies from 80 to 400 mm, usually with TX fitting. Wood bolts or coach screws Wood bolts or coach screws have a hex head and are available from M5 to M8 in lengths from 30 to 100 mm. These bolts are used to support heavy loads. For example they are ideal for hanging central heating radiators, fixing a beam or joist to a concrete floor, or securing heavy table legs. To tighten the hex head, use a wrench or socket.