Fasteners
Thread-cutting screws: how do they work on pre-painted sheet metal?
When fastening metal components, screw geometry can affect both ease of installation and proper thread formation. This becomes even more important when working with pre-painted sheet metal, where the surface coating can interfere with the contact area between screw and metal.
For these applications, Kilton offers thread-cutting screws for metal, featuring a special 45° cut at the root of the thread. This geometry provides a cutting action during installation, facilitating thread formation and, in the case of pre-painted sheet metal, locally removing the coating from the contact area.
How do thread-cutting screws work?
A self-tapping screw forms its mating thread in the material as it is driven into the material, eliminating the need for a preliminary tapping operation.
In Kilton’s design, this function is combined with the thread-cutting action generated by its specific thread geometry. The 45° cut produces a cutting action as the screw penetrates the material. The purpose is to facilitate thread formation while reducing installation torque.
How does the 45° cut work on pre-painted sheet metal?
The paint on the sheet metal surface creates an additional layer directly in the fastening area. The thread-cutting geometry of the screw acts locally on this coating: as the screw is driven, the 45° cut removes the paint from the contact area, preventing the coating from interfering with proper screw installation.
The result is more direct and effective contact with the underlying sheet metal. The same cutting action also contributes to thread formation, therefore combining two functions that are particularly useful when assembling pre-painted metal components.
Features of the Kilton thread-cutting screw
This type of thread-cutting screw has no pointed tip and features a pan head with a Phillips cross recess.
The screw is manufactured from 1018-1022 material and has a minimum surface hardness of HV0.3 450. Core hardness ranges from HV0.3 270 to 390.
As for the applicable standards, the head is specified according to UNI 6954 B / DIN 7981 F, while the thread complies with DIN 7970 B.
The range includes four nominal diameters:
- 2.9 mm
- 3.5 mm
- 4.2 mm
- 4.8 mm
Full dimensional and technical details are available in the technical data sheet >>
For designers, manufacturers, and assembly managers, this screw is therefore a technical solution worth considering when fastening directly to metal components, including pre-painted sheet metal.
Contact the Kilton experts to select the most suitable fastening solutions for your industrial projects.
