The Somta Extra Long Series Drill - HSS-E Parabolic Flute, sized at 12.5 mm diameter and 375 mm overall length, is purpose-built for deep-hole drilling where reach and hole quality matter most. This is a tool that doesn’t just reach into the workpiece—it maintains rigidity and precision all the way to the bottom, delivering dependable results in challenging setups.

Why this drill stands out

• HSS-E construction combines the toughness of high-speed steel with enhanced wear and heat resistance, helping the bit hold a sharp edge through demanding materials and extended cutting times. The result is longer tool life and more consistent hole quality, even as depths increase.
• Parabolic flute geometry is engineered for efficient chip evacuation. By guiding the chips smoothly away from the cutting edge, it minimizes chip recutting, reduces heat buildup, and lowers the risk of clogging when drilling deep holes.
• Extra-long reach—with a 375 mm length, this drill is designed for deep bores, blind holes, and pockets that standard bits can’t access. The extended flute also helps dampen vibration, contributing to straighter holes and cleaner finishes.
• Clean, accurate hole quality thanks to sharp cutting edges and optimized flute geometry. The combination delivers true starts, minimal wandering, and reduced burr formation in a variety of metals.

Ideal applications and use cases

• Deep-hole threading or bore operations in automotive components, aerospace hardware, and heavy machinery housings where access is limited.
• Mold and die work requiring precise, through-holes in steel, aluminum, cast iron, or alloyed materials.
• Maintenance and repair tasks where a long reach is essential to access recessed areas without removing the workpiece.

Performance tips for best results

• Match spindle speed and feed rate to the material and hole depth. Start with a conservative feed and increase progressively as the cut stabilizes to maintain a clean chip load.
• Use peck drilling or gentle intermittent advances to break up and evacuate chips. This prevents chip buildup that can impede cutting and affect hole straightness.
• Coolant or generous lubrication helps manage heat at depth. Keep the cutting zone cool to extend tool life and preserve hole quality.
• Secure the workpiece firmly and use proper work-holding to minimize deflection. A stable setup is essential when using an extra-long drill to prevent deviation.

What you can expect in real-world operations

• Reliable performance across a range of metals, with durable edges that stay sharp longer under typical deep-hole workloads.
• Consistent hole geometry from the entry to the bottom of the bore, reducing the need for rework or secondary finishing passes.
• Greater versatility for workshops that encounter recessed features or parts with limited access, enabling more efficient production without changing tools.

With the Somta Extra Long Series Drill, you’re equipping your shop with a dedicated deep-hole solution that pairs robust HSS-E durability with a parabolic flute design to keep chips moving and holes clean. It’s a specialized bit that delivers dependable depth, precision, and control when the job demands every millimeter of reach.