In contrast to the single-slot drive, the cross recess drive (also known as a Phillips drive) offers the advantage that the screwdriver blade can no longer slip out to the side and cause damage to the workpiece. Due to the tapering of the inner flanks in the cross recess, however, an axial force occurs when the screw is tightened, which pushes the blade out of the drive. This phenomenon is also known as the cam-out effect. The cross recess H drive is also used on our window construction screws (FEX), since the screwing-in torque is not too high. What this means for you: A simple Phillips screwdriver is all you need to install your windows quickly and securely.
The countersunk head (or flat countersunk head) is the most common head geometry in the world of SPAX. It has a conical shape and, in the case of SPAX, is characterised by the 90° MULTI head. Our countersunk head screws offer the ideal compromise between maximum resistance to tightening torques and a discreet and attractive screw connection. With its polygonal underside ("pockets"), the flat countersunk head mills its own way into the wood and can therefore be countersunk into the wood cleanly and flush without having to pre-drill the screw hole. What this means for you: Flush screw insertion becomes child's play – with no need to pre-drill or countersink the screw hole.
Coarse threads are predominantly used in wood construction, where screws have to be fastened quickly. Screws with coarse threads form their own counter-thread in the wood and are self-drilling. Unlike sheet metal screws with a fine thread, the force transmission with coarse-thread screws not only takes place over a few millimetres of the sheet metal, but over the entire thread length. This is why the thread turns can be arranged further apart. In addition to our wood construction screws, we have also equipped our GIX B drywall screws with a coarse thread. These screws are used for wood stud framing. What this means for you: Faster, battery-saving insertion of screws in all wooden substructures, perfect force transmission between thread and wood.
In some areas, wood attachments have to be fastened to metal substructures, such as with our SPAX aluminium decking screw or in dry lining. Since normal screws would quickly meet their limit against hard metal, our range also includes screws with a special drill point. From the outside, it is reminiscent of the point of a metal drill, with two small blades. The SPAX aluminium screw drills into aluminium with wall thicknesses up to 4 mm to enable the thread to furrow into the material. This makes them just as easy to insert as our wood construction screws. What this means for you: With wall thicknesses of 2 mm in metal and 4 mm in aluminium, there is no longer any need for the otherwise customary pre-drilling with a metal drill. No having to change bits, no thin metal drill bits breaking in the screw hole.
Effective corrosion protection is a must for screws used for outdoor structures not exposed to the elements. For this, SPAX has developed the WIROX coating, which far outdoes conventional galvanisation in terms of both protection and durability. Our WIROX-coated screws are significantly more resistant to mechanical stress than their counterparts with chromate conversion coating. No chromium(VI) is used for WIROX, which means that even after years in an area not directly exposed to the elements, the screws are not only just as resilient, but are entirely environmentally friendly, too. Our WIROX screws are the ideal choice for all open structures without direct exposure to the elements, such as carports and pergolas. For areas with extreme weather exposure, such as decking, we continue to recommend our stainless-steel screws.What this means for you: When you use our corrosion-protected screws outdoors, you can be safe in the knowledge that your structure is well fastened – in outdoor areas not directly exposed to the elements, WIROX keeps our screws statically rigid and reliably protected over many years. So there's no need for visual inspections every year!