Wood screws are the classic connection means. They are easy to process, have the highest holding values and they can be used universally.
A distinction is made between the classic wood screws with a slot- or hexagon head for solid wood and the modern ones, Multipurpose screws particularly suitable for chipboard and wood-based materials (Spaxschrau-ben) with Phillips head.
The conventional screw with a slot is available with a flush countersunk head (DIN pool 97), the semicircular round head (Ruko DIN 96) and the slightly protruding lens head (Liko DIN 95). Larger dimensions are also available with the usual hexagon head for machine screws (DIN key screws 571). In the norms (FROM) are all screw data such as thread diameter, Usable length, Thread length, Head diameter, The width and depth of the slot and, in the case of hexagonal heads, the width across flats are determined.
Standards and dimensions
Standard screws are available in diameters from 1,6 to 8 mm and in lengths of 8 to 80 mm. In the case of key screws, the diameters range from 4 to 20 mm and the lengths of 16 to 200 mm. The effective length is calculated as the length, the largest shaft diameter as the diameter. The length of the thread is at least equal to 60 Percent of the smooth shaft length.
Material and surface
Slotted screws are made of steel, Brass and rustproof made of A2 steel and aluminum. Steel screws are also galvanized, chromatiert, brass-plated or burnished. Brass screws are bright, burnished, nickel-plated or chrome-plated. The latter are used specifically in the sanitary area. Aluminum screws are usually anodized in gold or silver. Key screws are usually galvanized, Made of stainless steel or galvanized and powder-coated in brown or white for use with garden wood.
The most important data are noted on the screw packaging. There is material and surface treatment, Thread diameter, Long, Head shape and DIN number can be found. Colored markings on the labels assign the content of a screw type. Large screws can be bought individually, Standard sizes come in small packs or each 50, 100 or 200 Packed in cardboard boxes.
Spax screws
The name Spax screw is a registered trademark of the screw manufacturer Altenloh, Brink & Co., but has established itself as a general term for multi-purpose screws. Spax screws have a sharper thread than normal wood screws, a thinner screw core, a sharp gripping point and a sliding coating. The thin core leads to a lower displacement resistance and in most cases only requires pre-drilling in the part to be fastened.
The Pozidriv cross-slot is used as the drive for these screws (in four different sizes) enforced. Lately the screws are also with a Torx head (in six sizes) to have. Both systems make working with electric screwdrivers possible. The head shapes (except for the hexagon head) The wood screws largely correspond to those of the standard wood screws. In most cases the material is hardened steel, A2 (rustproof) or brass. Steel screws are galvanized, White- or. yellow chromated or burnished. The diameters range from 3 to 6 mm, the useful lengths of 13 to 240 mm.
Color coding system for orientation – Thanks to a color coding system, you can quickly find your way around when buying screws. The labels on packaging for steel screws are green, those of brass screws yellow. The stickers for countersunk screws are one color, with a button head they have a red one, a white stripe on the lens head.