Any tradie who handles metals and drills understands that it is necessary to use the correct bit to bore holes quickly and with ease. If you are looking for tips for choosing the right drill bit for boring through metal, you need to understand the tips for drilling, the proper way to use a hand power drill, and how drill bits can be sharpened. You also need to know how to choose the right drill bits for metals.
You’ll find a variety of choices when you look for drill bits for metals. They can be
- Titanium coated or cobalt steel
- Metal hole saw
- Unibit (step bit)
Let’s now take a closer look at these.
High-speed steel bits or HSS bits are made of carbon steel along with other elements such as chrome and vanadium. This makes them perfect for using at high drilling speeds. An HSS bit can be used to drill a wide range of materials such as iron, steel, brass, copper, and aluminium among others.
Titanium coated bit
HSS bits with a coating of titanium have more durability and hardness than HSS bits. This makes them suitable for drilling hard materials such as stainless steel. However, it is to be remembered that the titanium coating will eventually wear off, and if you sharpen these drill bits with a drill bit sharpener or by hand, you will lose the coating totally. In appearance, the Titanium bits look like HSS bits with a brass or orange colouring.
Cobalt alloy bits are also another option. They are made from solid alloy, and not just coated like the titanium bits. Cobalt makes the drill more durable and it can endure higher temperatures while drilling without losing their edge. However, these drills tend to be more expensive and brittle. Hence they are likely to chip at the edge.
For drilling very large holes, bigger than 1.5 inches, you need a drill with a lot of power and torque to overcome friction. That’s where a hole saw comes in handy. They can be used to drill large holes. Hole saws have small teeth like a handsaw with a cylindrical blade. Some hole saws are made from HSS steel, making them suitable for drilling iron, steel, and other metals.
Step Bit (Unibit)
Step bits or unibits are conical shaped bits with multiple cutting edges of varying diameters. They are suited for drilling thin softwoods, laminates, chipboard, plastics, plasterboard, and sheet metal. Step bits are ideal for electrical drilling, especially if you need different sized holes to be cut in junction boxes, panels, etc. They are convenient because they make it possible to drill holes of different sizes without changing bits. Also as the bit comes to a point, a pilot hole is not required if a large hole needs to be drilled.