A Lazy Guide To Using Cobalt Drill Bits
Even if you already have a set of cobalt drill bits, drilling hard metals can be intimidating, but it is a skill you can master in relatively little time, if you have the right tools and know the right techniques. This article will get you started the right way.
Use the right kind of power drill.
Cobalt drill bits are only part of the equation – you also need the right drill. If you’re not in a workshop environment, this will almost always be hand drill. For any kind of metal drilling, you’ll want to use a variable speed power drill.
If you’re choosing between 2 different drills for metal, choose the one with the slowest speed setting, not the highest (all else being equal). You’ll get more work done faster at a lower speed.
If you are buying a new drill, you’ll want to look for a large, powerful motor. Ne next consideration is power – will you always be near a socket? If so, a wired power supply is ideal. If not, choose a drill with ahigh capacity battery or easily changed battery packs.
Consider using a metal lubricant or cutting paste.
Cobalt drill bits can withstand more heat than other HSS bit types, but you may still need a drilling paste to reduce friction and keep the heat down to manageable levels.
Metal drilling oils and pastes can allow you do drill for longer stretches of time, but may be messy. You can usually get by without lubricants of you are using the right drill bits and only working for 10 seconds at a time, but for the hardest metals and the biggest jobs you’ll wish you had gotten a small tin of lubricant paste.
Wear your PPE!
Cobalt drill bits are brittle, and an accident can cause them to shatter. Most metals will shed razor-sharp turnings and shards of material when drilled. You don’t want anything like that anywhere near your eyes, so wear goggles. You can’t afford to be breathing sharp and potentially toxic metal dust, so wear a breathing mask. You will definitely need all of your fingers to finish this project, so wear gloves. You see where I’m going with this…
Ease onto drilling – start slow.
Cobalt drill bits will allow you to drill a wide variety of hard metals, even if they aren’t always the perfect choice. If you don’t have any experience drilling into a particular type of metal, always begin cautiously.
Drill at low speeds, particularly at first. Some metals (like stainless steel) can ‘work harden’, and drilling them at high speeds is much more difficult than if you keep the speed low. Drill only for 10 seconds at a time, and then wait at least 20 seconds to allow your drill bit to cool. You can probably get away with less waiting time using cobalt drill bits, but why risk it?
