Drill bits are cutting tools that are used to remove different types of materials to create a hole, generally always in a circular motion. Having the right size and the right type of bit is a key factor in ensuring the highest standard of work and ensures you can drill with confidence and accuracy. Learn more in our complete guide to drill bit sets.
What materials materials used for drill bits?
- Carbon Steel – This material provides a drill bit with better durability and hardness, therefore increasing the life of the bit. Carbon steel can withstand higher temperatures and is more suitable for harder materials.
- HSS (High-Speed Steel) – HSS can withstand higher temperatures without compromising the hardness of the bit and is able to cut faster with more accuracy and efficiency.
- Cobalt Steel – The cobalt content increases the strength of the bit and aids in the resistance to heat and friction, so it can be used for more stubborn materials.
- Tool Steel with Tungsten Carbide Tips – TCT provide a longer working life for the bit, while allowing for a more stable and solid tip and enabling it to withstand more rigorous drilling applications.
What coatings are used to enhance drill bits?
- Black Oxide – An economical coating that prevents corrosion and increases stress relieving at the bit. It also helps in retaining drilling lubricants for longer and is most suitable when drilling iron and steel.
- Bronze Oxide – This coating increases stress relieving of the bit. It is normally used on its own so that it is easy to identify cobalt steel. It can also be used with black oxide to better identify higher grades of HSS.
- Titanium Nitrate – This coating increases the hardness of the bit, whilst providing a thermal barrier for high friction applications. It is a more expensive coating than others, but helps to increase production rates and tool life. TiN coated drill bits are best suited for drilling more stubborn materials like iron, steel, aluminium and more.
Common types of drill bits
- Twist – The most common type of drill bit and ideal for drilling wood, plastic, and metals. They are generally made from HSS and are suited to general household DIY tasks, as well as professional applications like maintenance and engineering. Masonry – The TCT drill bits are the best to use when drilling brick, block, stone and mortar and are most commonly used in the construction industry. They are generally used with a hammer power tool for more effective results. SDS (Slotted Drive System) – These have a special shank that fits into the chuck of an SDS power tool. The SDS system delivers a higher standard and more efficient results than a standard hammer drill when working with harder materials like concrete.