What type of drill bit do I need for metal?

By: HowStuffWorks.com Contributors  | 
A close up of a milling machine drilling into metal.
Metal drill bits are more expensive but worth it if you do a lot of metal work. vitapix / Getty Images

Drilling through steel is not an everyday home repair activity, and drill bits for metals are the most expensive. Regular drill bits can't cut through steel, so you need a heavy-duty, hard drill bit to do the job. There are two types of drill bits that you can count on for metalworking projects: titanium and cobalt.

Titanium drill bits are high-speed steel drill bits (HSS) that have a titanium oxide coating. They are very hard, and corrosion-resistant. They last much longer than regular HSS drill bits, and they are good for cutting through any metal, including metal sheeting. Titanium drill bits are harder than cobalt, but because they are coated, they can't be sharpened. Cobalt drill bits are made of cobalt steel, and they can be sharpened. They are especially good for drilling through stainless steel, cast iron and titanium. While these drill bits are very hard, abrasive and highly resistant to heat, be sure to start slow when using them as they can break at high speeds.


Originally Published: May 18, 2011

Metal Drill Bit FAQ

What is the best drill bit for metal?
Conventional drill bits cannot cut through metal so you need a heavy-duty, hard drill bit. Two types of drill bits are suitable for metalworking jobs: titanium and cobalt.
What is a cobalt drill bit?
As the name suggests, cobalt drill bits are made of cobalt steel. Unlike titanium drill bits, they can be sharpened. Cobalt drill bits are very hard, highly heat-resistant, abrasive and ideal for drilling through cast iron, stainless steel and titanium.
How do you know if a drill bit is for metal?
Usually, drill bits that are for metal can be distinguished by their black color. They are also usually made from tungsten carbide, cobalt or titanium, which should be noted on the packaging if you’re buying new. Another easy way to distinguish these from conventional drill bits is to check if they have a wide-angled point at the end.
Can you use metal drill bits for wood?
Whether you can use metal drill bits for wood or not depends on the wood type and the type of drill bit used. Most metal drill bits increase splintering and tear-out when you use them for wood. However, titanium drill bits tend to be fine for this application.
Which is harder: cobalt or titanium drill bits?
Titanium drill bits are harder than cobalt, but cannot be sharpened as they're coated, not solid titanium,.