Shown here is a TiN-coated drill bit. Titanium Nitride can often be easily identified by its golden color.
TiN is a hard ceramic coating that is often used on steel drill bits and other machine tooling, and it provides several benefits, mainly longer edge retention and reduced friction.
In other words, TiN-coated drill bits should last longer than uncoated bits, and you can often push them faster too.
It does have its downsides. For example, you can’t use TiN-coated drill bits on aluminum. Well, you can, but you run the risk of having the aluminum smeared all over the drill bit, leading to worse performance or other complications. There are ways around this, but many manufacturers don’t recommend the use of TiN drill bits on aluminum.
I use TiN-coated bits on wood, because it’s convenient. When I drill steel, I use HSS, TiN, or cobalt drill bits. Or black oxide if it’s light duty work and that’s all I have around.
Different drill bit coatings and materials have different benefits and tradeoffs.
The other day, I posted about a Makita wood, metal, and masonry drill bit set, and saw some strong dislike for TiN-coated drill bits. This brought me to wonder:
What do you guys think about TiN-coated drill bits?
There are other gold-colored drill bit coatings, such as gold oxide, and gold ferrous, which is what certain Dewalt PilotPoint bits are coated with. It’s been hard for me to find any solid details about these types of drill coatings. According to a few machining forum posts, they’re a step below TiN.
Speaking of which, although I have industrial bits at my disposal, I still love my Dewalt’s 29pc PilotPoint drill bit set ($53 via Amazon and eligible for their holiday discount) for drilling into wood and plastic, and I use them on occasion for light metal drilling as well. Then again, I’ll use them for things like 1/8″ aluminum plate, and not 1″ aluminum bars and things like that.