Which Drill Bit To Use
You know a drill really only has one job–make a hole. But what you're making a hole in dictates the type of drill and bit you actually need. Watch my favorite Canadian mechanic break down the which, what and why of every drill type you'll ever mess with and some you've probably never seen.
Returning Jalopnik readers might recognize YouTuber AvE from a previous post. The dude is a legend– always dismantling and explaining tools for our education while making up funny cuss words.
If you've ever wanted to know which drill bit you need to get a certain size hole through a given material, why punch tools are useful, why different bits are shaped the way they are or how fast and hard to run your drill while it's working this joint has your answers.
Most of your DIY drilling projects are probably going to require the simple "twist-bit"—that's the standard twisted sharp stick you probably think of when you picture a drill in your mind. For making small holes into wood, plastic or softer metals getting the right twist bit is mostly a matter of getting a decent-quality one made of the right material and not letting it get too hot while you're drilling.
Other bits are designed to pull themselves through material like an "auger bit" or "self-feed" that tend to leave cleaner exit holes in soft stuff and come in handy when you're making furniture.
This video takes us through a "hierarchy of materials" from soft to hard. In this context, the "easiest to hardest to drill through." You probably already understand that "steel always beats plastic and wood" in that regard, but I like how AvE explains the toughness of metals via types of cheese.
If brass is brie, aluminum is gouda and steel is cheddar. Tool steel, apparently, is like parmesan that's been sitting in a freezer for a week.
For cutting through that "frozen parmesan" AvE has some seriously badass bits on display, with internal cooling channels that can only be run by heavy, fixed machines. On the smaller stuff that you'd put in a hand drill, he recommends a "medium pressure and a medium pace." If you're making heat instead of a hole, you're pressing too hard or spinning too fast.
That said, spinning your drill bit too slowly can actually be worse than overclocking it because it will be more susceptible to breakage under the "200 pound gorilla pushing on it" (he means you).
The key takeaways from the video are basically to spin your bit at the right speed and pick one made from a material that's harder than the one you're boring. And make sure your stuff doesn't get too hot.
Did you know you can file a nail into a redneck drill bit? This and all the other gems of drilling knowledge you never knew you needed are in the vid.