TCT HOLE SAWS

Neither Large Diameters nor Hard Materials Can Stop Them

Drilling into metal with a conventional twist drill bit is a common method that is highly effective for smaller hole diameters. Twist drill bits feature a helical design and remove material across the entire area of the intended hole. However, when drilling larger diameter holes that require removing a significant volume of material, this process becomes both time-consuming and energy-intensive. It can also lead to excessive tool wear and overheating of both the drill bit and the workpiece.

This problem can be solved efficiently by using annular cutters, which remove only a narrow ring of material around the circumference of the future hole. Because significantly less material is removed, both drilling time and tool load are greatly reduced. One of the most common and versatile tools based on this principle is the bi-metal hole saw.

For professional applications and drilling into very hard and tough materials, however, carbide-tipped annular cutters are a far better choice thanks to their exceptional hardness, long service life and high drilling speed.

What Carbide-Tipped Annular Cutters Look Like and How They Work

Carbide-tipped annular cutters feature a distinctive design consisting of several important components:

Carbide-tipped annular cutter - component overview

• One-piece construction: The cutter and shank are manufactured as a single piece, providing maximum rigidity and stability.
• Hex shank: The shank is compatible with both drill presses and handheld drills, ensuring a secure grip while reducing the risk of slipping or loosening during operation.
• Pilot drill: The pilot drill ensures precise positioning by defining the centre of the hole. It also provides stability and accuracy during the initial drilling stage. If worn or damaged, the pilot drill can be easily replaced.
• Cutting teeth: The teeth are positioned around the circumference of the cutter and are made from carbide. As the tool rotates, they progressively cut material only around the edge of the hole.
  Depending on the language or manufacturer, carbide may also be referred to as SK (Sintered Carbide), HM (Hartmetall) or TC (Tungsten Carbide).
• Hollow cutter body: Thanks to its hollow centre, there is no need to remove the entire volume of material. The cut-out slug remains inside the cutter during drilling.
• Spring: The spring mounted on the pilot drill makes it easier to eject the slug from inside the cutter, making work faster and more convenient.

Carbide-tipped annular cutters therefore provide an efficient, accurate and fast solution for drilling hard metals where high quality and productivity are essential.

Applications

Carbide-tipped annular cutters drill efficiently through alloyed and non-alloyed steels up to 1300 N/mm², V2A and V4A stainless steels, as well as non-ferrous metals. They can also be used on plastics, laminated chipboard and plasterboard.

Drilling on a flat surface

Drilling on a curved surface

Drilling at a sharp angle

Available Diameters and Cutting Depth

Carbide-tipped annular cutters are available in a wide range of diameters, allowing you to choose the ideal size for virtually any application. OREN offers these annular cutters in sizes from 15 mm to 100 mm. The cutting depth is 12 mm, making them shallow-cut cutters. This makes them suitable not only for drill presses but also for handheld drills, as their shallow cutting depth requires only light feed pressure.

Maximum cutting depth depends on the material being drilled.

Advantages and Disadvantages of the Short Cutting Depth

• Increases the strength and rigidity of the cutter, reducing the risk of breakage or damage when drilling hard materials.
• Minimises cutter deflection during drilling, resulting in greater accuracy.
• Provides improved heat dissipation and more effective cooling. This is particularly important when drilling hard materials where high temperatures are generated.
• Limits the maximum drilling depth. For deeper holes, other tools such as conventional twist drill bits or bi-metal hole saws should be used.

Best Practices for Maximum Performance

1. For maximum drilling accuracy and stability, carbide-tipped annular cutters should preferably be used in drill presses. These machines provide secure and rigid tool holding, minimise vibration and ensure highly accurate drilling.
2. When using a drill press, use manual feed only. Automatic feed can overload the cutter and lead to premature wear or damage.
3. Apply light and even feed pressure while drilling. Excessive pressure may overheat both the cutter and the workpiece, causing damage. Insufficient pressure, on the other hand, can slow down drilling and result in poor cutting performance.
4. Avoid rocking or side-to-side movements. Keeping the drill stable ensures a clean and accurate cut. Rocking movements can cause irregular cuts and increase cutter wear.
5. Follow the recommended spindle speeds. Every material requires a specific speed for optimum cutting performance. Using the recommended speed charts for different materials can significantly improve drilling efficiency.
6. Use cutting lubricants and coolants: Coolants are essential for preventing overheating of both the cutter and the workpiece. When drilling metal, adequate cooling is crucial to minimise the risk of deformation and material damage. You can read more about lubrication in our article here.