WHEN SHOULD YOU CHOOSE COBALT DRILL BITS?
Posted by John Rennie on
Cast your mind back to your school days – did mention of the periodic table plunge you into dark doom, or did you skip to every physics lesson?
If you were anything like me, nothing I learnt in school had any real relevance to the real world. The Weimar Republic sounded like a trendy hot dog company, and atomic structure could have been the name of the latest rock band.
They say that youth is wasted on the kids, and it is only when you start working in a trade that you realise how important so many of those lessons were, particularly in maths, when you’re trying to work out how much money you have to last you to the end of the month before the next payday!
Everything about tools comes down to physics and understanding the properties of different metals and how they work together to ensure that performance and results relate to the real-world expectations of the job at hand. By that, we mean that to do a specific job, in a reasonable amount of time, at a competitive market price, is down to two key factors – the quality of the tools you are using and the skill and experience of the tradesman.
Setting good quality drill bits against poor quality drill bits will highlight the fundamental importance of choosing quality every time, even if it means a higher investment.
There are two elements to drill bits that you need to make sure are absolute when it comes to investing in the right tools (depending on your material, though we are focusing here on woods, metals, and plastics, rather than hard granites.)
Make sure your drill bits are HSS
The drill bit needs to be HSS. The meaning of HSS stands for High-Speed Steel. This is a tough, durable drill bit that is usually used for high-volume production drilling and tends to be much more robust and flexible than its cheaper carbon steel cousin. The best HSS drill bits will contain a mix of carbon, tungsten, cobalt, chromium, molybdenum, and other elements, which all add different properties, such as durability, strength, and corrosion resistance.
Molybdenum is a metal that is added to instil a degree of flexibility so that the drill bit does not break or snap.
Tungsten has the highest melting point of any metal. Its addition ensures the drill bit withstands the excessive heat generated as a result of a prolonged period of drilling, as well as adding to the overall strength of the drill bit.
Cobalt also adds to the heat resistance.
You can see now why physics and knowledge of the periodic table are so important when it comes to ensuring your drill bit investments are maintained. It’s never too late to learn and putting that knowledge into the context of your work brings it to life.
The importance of cobalt
While HSS drill bits have more than enough strength and durability for less intensive jobs, such as working in timber and plastic, cutting through steel and metals requires a higher percentage of cobalt.
Cobalt is a hard silvery-white magnetic metal with an incredibly high melting point of 1495°c and corrosion resistance. An HSS Cobalt drill bit is truly the Rolls Royce of the drill bit world – it can be operated at much higher speeds than standard HSS drill bits and can be employed in one continuous process for much longer without overheating due to its strong thermal properties.
HSS cobalt drill bits are ideally used for hardened and abrasive materials. These include hardened materials such as bronze, cast iron, stainless steel, and titanium. Despite their overall strength, cobalt drill bits are broken down further depending on the metal to be drilled. You will find, for example, that some cobalt drill bits also contain varying amounts of titanium, titanium nitride, and tungsten carbide. Rennie Tool Company can guide you towards the best choice for the job at hand.
The benefits of choosing the best UK HSS cobalt drill bits
Time and money are the ultimate benefits you and your business will experience by putting thought, care, and a good investment into the quality of your drill bits.
By choosing the right drill bit for the right job, you will avoid any unnecessary breakages. If a drill bit is broken, you have both the expense of replacing it with a new bit, but also, you are losing out on the time it takes to change the drill bit – and when working at high speed, that is a big chunk of productivity that is lost.
The drill bit is just as likely to break if it is too good for the job – by that, we mean that if you use a cobalt drill bit for a less intensive job such as plastic or wood, it can be just as detrimental as using an HSS drill bit for cast iron. It is for this reason that it is so important that you understand the true properties of the drill bit that you are choosing and the job you are selecting them for.
So, ensuring that you select the correct drill bit for a specific job will give you another area for both time- and money-saving.
Maybe you weren’t the best student when you were at school, but a good working knowledge of the direct costs involved in a drilling job weighed up against the expenses incurred by not choosing correctly, will give you a loss figure that will have a detrimental effect on your business.
Increased product knowledge and awareness and asking the right question of your tool supplier will go a long way to redressing these calculations and turning those losses into a healthy profit margin.
Our advice at Rennie Tool Company is to always be asking the question. If you were one of those students that hated putting your hand up in class out of embarrassment – then please do not worry. Our one and only aim is to help you make the right choice without fear of judgement. We want our tradesmen to be making money, not losing it!
If you would like to discuss your tool requirements in more detail, then feel free to contact us directly.