Somta Long Series Drill - HSS-E Parabolic Flute - 4.7mm

The Somta Long Series Drill in HSS-E with a Parabolic Flute, 4.7 mm diameter, is purpose-built for serious deep-hole drilling where shorter bits fall short. Its extended reach cuts cleanly through thick workpieces, delivering precise, reliable holes from the first entry to the final exit.

• Long-reach design—optimized for through-thickness drilling and deep boss or cavity work where access is limited.
• HSS-E construction—enhanced High-Speed Steel for superior durability, heat resistance, and long tool life under demanding cutting conditions.
• Parabolic flute geometry—facilitates aggressive chip evacuation, reduces cutting forces, and lowers friction to keep the edge cooler during extended cuts.
• Sharp, precise cutting edges—ground to produce clean, round holes with minimal wander, even in tough alloys.
• Efficient heat management—flute design and geometry work together to minimize heat buildup, helping prevent premature wear and keeping tolerances tight.
• Versatile performance—well-suited for steels, stainless steels, cast irons, and other common metal alloys encountered in fabrication, aerospace, and automotive applications.
• Reliable in standard machining setups—ideal for drill presses and CNC centers where precision and stability are critical for repeatable hole quality.

Use cases and real-world applications

When you need a hole that reaches beyond typical depths without sacrificing accuracy, this 4.7 mm Somta drill shines. It’s a go-to choice for drilling through thick plates, fixtures, or metal assemblies where consistency matters—from prototype rigs to production jigs. The parabolic flute keeps chips moving away from the cutting edge, reducing clogging and allowing you to maintain steady feeds and speeds without overheating the bit.

Practical tips for best results

• Secure the workpiece firmly and use a center punch or pilot assist if starting a hole in hard material.
• Match cutting speed and feed rate to the material and depth—the HSS-E composition tolerates higher speeds, but avoid overheating by using light lubrication or cutting fluid when machining reactive metals.
• Let the flute carry most of the chip load; avoid plunging aggressively without adequate support to minimize deflection.
• Periodically back off to check hole diameter and ensure clean exit; replace or re-sharpen if you notice edge dulling or chip thinning.

Why choose the Somta Long Series Drill over standard bits? Because the combination of long reach, HSS-E durability, and parabolic flute technology translates to deeper, cleaner holes with less effort and fewer tool changes. This is a drill bit that stays true under pressure, maintains hole quality through bulkier materials, and delivers repeatable results across a range of metals—making it a dependable workhorse in any machine shop or fabrication environment.