Start by marking the intended hole position clearly. On a smooth metal surface, use a center punch to create a small indentation. This gives the drill-bit tip a defined starting point and reduces wandering during initial contact.
Secure the workpiece with a clamp or vise. Metal should not be held by hand during drilling, especially when working with thin sheet metal or larger drill bits. As the drill approaches the opposite side, the bit may catch the remaining material and rotate the workpiece unexpectedly.
Choose a drill bit that matches both the metal and the intended hole size. Check that the drill bit is sharp and installed centrally in the chuck.
Set the speed before the drill bit contacts the surface. Avoid immediately using the maximum 2000 RPM. Begin with a controlled speed suitable for the drill-bit diameter and material.
When using ST3, place the detachable Front Guide Head flat against the work surface. Confirm the drilling position, reset the depth measurement when needed, and apply steady forward pressure.
Allow the cutting edges to remove the metal rather than forcing the drill bit through it. For deeper holes, periodically withdraw the bit to clear chips. Suitable cutting fluid can also help reduce heat when drilling steel or stainless steel.
As the drill bit approaches the rear surface, reduce feed pressure. The remaining layer of metal requires less cutting force, and excessive pressure during breakthrough may cause grabbing or create a larger burr.
After drilling, use a deburring tool or countersink to remove sharp edges when required.