Making smaller better. Sandvik’s CoroDrill 862 with -GM geometry supports quality in small part machining

The growing need for smaller electronic parts presents real challenges for manufacturers, including in processes like micro drilling that involves producing holes smaller than 3mm in diameter. Micro drilling techniques are used to produce components ranging from aerospace components, hydraulic valves, watch cases and medical devices to surgical instruments, electronics, actuators, sensors, navigational systems and more.

But what are the challenges? In particular, manufacturers are increasingly required to machine small, intricate components from difficult-to-machine materials like Inconel, stainless steel, ceramics and titanium. It can be difficult to machine these materials cost-effectively while maintaining the utmost quality. Flawless surface finishes are as important for aerospace components as for fibre optic connectors.

To compete in the growing EMS markets, manufacturers must maintain the highest levels of quality control, while also reducing any issues in the production process that can cause excess scrap or downtime. How can manufacturers rise to these challenges, while remaining competitive? The answer lies in high performance drilling solutions.

Longer-lasting tools
Manufacturers have found that micro drills can exhibit inadequate tool life when machining tough workpieces, like those made from ISO M materials. In these cases, the design, geometry and type of coating of the drill significantly impacted their performance and durability.

In response, Sandvik Coromant has introduced two new micro drills: CoroDrill 462 with -XM geometry and CoroDrill 862 with -GM geometry. The tools are ideal for precision drilling in industries that deal with small parts such as medical, aerospace, automotive, general engineering, electronics and watch-making among others. This range of micro drills are available to support machining in all ISO materials, P, M, K, S, O and H. The new geometries offer a wide range of cutting diameters and lengths.

In other words, the quality of the micro drill makes all the difference to quality of the final machined product. But to what extent? To answer this question, Sandvik Coromant performed a test.

Quality output
Sandvik Coromant tooling specialists compared the performance of a major micro drill competitor’s tool against the CoroDrill 862 with -GM geometry.

Each tool was run on a DMG Mori Seiki Milltap 700 machine, for the purpose of drilling blind holes in an ISO M 316L stainless steel workpiece. The same tool setting was used in each case, a cutting diameter of 2.5mm with a speed of 40m/min and a feed rate of 0.04mm/z.

The result was the competitor’s tool produced 630 holes before reaching tool life. CoroDrill 862 meanwhile produced 1 260 holes, a more than 100% increase in tool life over the competitor’s drill.

Sandvik Coromant’s engineers recommend that customers seeking to drill micro-sized holes in notoriously difficult-to-machine materials, such as titanium, aluminium, glass and ceramics, should consider polycrystalline diamond (PCD) coating for extended tool life in these demanding applications. It’s also critical to have quality coolant to effectively evacuate chips when performing deep-hole drilling with micro tools.

These features have clear advantages for manufacturers’ overall operational expenditure (OPEX), and can also help manufacturers strike a balance between quality versus productivity when micro drilling tough materials like ISO M. In doing so, to paraphrase Steve Jobs, they can ensure the small things are unforgettable for all the right reasons.

For further details contact Sandvik Coromant on TEL: 010 500 2295 or visit