STAINLESS STEEL HEXALOBULAR RAISED COUNTERSUNK CHIPBOARD SCREWS

Hexalobular Raised Countersunk Chipboard Screws — This part-thread version pairs a raised countersunk head — the same countersunk base as a standard chipboard screw, with a domed top that sits slightly proud — with a shank built to clamp two pieces together rather than grip a single board along its full length. The plain shank section beneath the head passes freely through the clearance hole of a top component, so the screw draws that component down onto the board beneath as the threaded section engages, forming a tight, clamped joint; that's the deciding factor for choosing this over the full-thread version, which is built instead for fixing straight into a single thickness of board. Because the head sits slightly proud rather than fully flush, it's the visible-fixing equivalent of the standard hexalobular countersunk screw, often paired with a cup washer for a more finished look where the fixing remains on show. Hexalobular drive gives noticeably better resistance to cam-out than Pozidriv under sustained torque, which matters most where these screws are driven in volume with a power tool — production furniture and shopfitting work in particular. Chipboard screw thread form generally follows the DIN 7505 specification, using a coarser, sharper flank than a traditional wood screw thread, since particleboard's compressed particles need the thread to cut and grip mechanically rather than wedge between long fibres. A2 (304-equivalent) is the right, economical grade for almost all chipboard furniture and fittings assembly, which is overwhelmingly indoor work. A4 (316-equivalent) is worth the extra cost mainly where a visible fixing sits somewhere persistently damp or humid, since staining on an exposed domed head is more noticeable than on a flush or hidden one. Sizing means matching gauge to the fitting's clearance holes and length to give solid thread engagement in the board beneath, without the screw bottoming out before the joint clamps tight.

FAQs
How does the part-thread shank work?
The plain shank passes freely through a clearance hole in a top component, so the screw draws that component down onto the board beneath as the threaded section engages, forming a clamped joint.

How does this differ from the full-thread version?
The full-thread version threads the entire shank for engagement into a single board; this part-thread version instead clamps a top component to the board beneath it.

What are these screws typically used for?
Fixing a component or fitting to chipboard where a countersunk-style, slightly domed head is wanted and the joint needs to be drawn together, rather than driven straight into a single board thickness.

Is this suitable for a visible fixing without a cup washer?
Yes, the domed head can be used without a washer, though a cup washer is a common addition where the fixing is visible, both to protect the board surface and improve the finished appearance.