VHM center drills from Nachreiner for precise pilot drilling

Without pre-drilling, metal drills tend to wander. This can happen either right at the start, potentially damaging or at least scratching the surface due to poor centering outside the intended hole, or by positioning the drill incorrectly on the drilling point, causing the hole to increasingly deviate from the ideal center as the drilling progresses. The deeper the hole, the more noticeable even minor misalignments become on the workpiece. Such issues, especially in large-scale production, can lead to a significant amount of scrap or at least reduced quality. To prevent wandering, the use of VHM center drills is recommended. The solid carbide (VHM) version of this tool is ideal for difficult-to-machine metals and other materials that require absolutely precise pilot holes. VHM center drills differ from other metal drills primarily in their shorter length, as they are intended solely for centering purposes and are not suitable for drilling deep holes. Even if the length is sufficient, VHM center drills should not be used for drilling actual holes, as they lack the necessary guide chamfers. Instead, the VHM center drill ensures that a precise pilot hole improves the guidance of the main twist drill, allowing it to be positioned accurately for the final drilling. Additional applications for center drills include creating support points for live centers, which support particularly long workpieces or facilitate turning between centers. Using high-quality center drills makes secure handling significantly easier.

Various types of VHM center srills available at Nachreiner

Our range includes different types of center drills. While HSS or HSSE center drills with tip angles of 60, 90, and 120 degrees are sufficient for many applications, the solid carbide (VHM) drills are designed for especially high loads due to their solid carbide construction. Their performance often surpasses that of HSS drills. If you need a specific size or another tip angle not listed under VHM center drills, please contact us directly. We can provide customized solutions for almost any project and will certainly be able to suggest an acceptable alternative. Custom-made center drills and other metalworking tools are also available. For personalized advice, it is best to speak with our specialist advisors. When ordering, please note that center drills (whether HSS, HSSE, or VHM) should not be confused with NC spot drills, which are primarily used in machine tools with particularly high geometric stiffness and stability. Unlike center drills, NC spot drills do not have a centering tip. They allow for a shorter machine-guided pilot drilling path and are also not suitable for deeper holes, which should generally be completed with a suitable twist drill. If using VHM for your center drills, we also recommend using VHM for twist drills and other tools when working with the same materials, as this promotes an even and clean final result.