Drill Bit Types and Their Uses
There are a large range and diversity of drill bits available when it comes to drilling holes. To make sure that you have the right one for the job we have put together this helpful drill bit guide that will hopefully leave you better informed about your choices.
One thing we would advise right up front is never do buy very cheap ones as quite frankly they will burn out fast, leave you very frustrated, and just cost you more money in the long run.
Cheap drill bits are ok for doing a one off job, but other than that we would recommend that you don't waste your money on very cheap products.
Good quality drill bits are not crazy expensive and with a little maintenance can last you for a very long time. It is worth paying a little extra to have something decent in your tool box.
List of Drill Bit Types
I was trying to figure out the best way to explain the many different types of drill bits to people who may not know. I have listed these just below, simply so as you know how many different types are actually available
Underneath the list is more useful information as I show which drill bit type is used for drilling through the various types of material.
Now along with these there are a whole range of what would be termed specialist drill bits and these are used by woodworkers, jewellers and glass makers.
We will not get into those in this particular article and will concentrate on the main drill types available today. So now we know that there are different types, so what exactly are they all used for and why.
Drill Bits for Different Materials
However, I though the easiest way to do this was to show what drill bit types are available for drilling through specific kinds of materials such as wood, plastic , metal etc.
In addition to that we also want to include the drill bits that will allow you to drill different sized holes.
Best Drill Bits for Masonry
The huge majority of people mainly buy a drill bit to make some type of hole in masonry. That is why we are starting with those. Masonry is a general term used to cover off bricks, blocks, walls, concrete, cement, stone and granite.
In other words very hard material, that needs a special drill bit all of its own. This is called a masonry drill bit, as shown in the image below.
As you can see these come in different sizes, which are measured by the diameter of the drill bit. You can buy these as an individual bit, but more commonly they are bought in sets, as shown above.
They have quite a distinctive arrow shaped head as you can see from the image, and quite a noticeable twist on the shank of the bit. That is to help move the masonry dust quickly out of the hole.
These are used in conjunction with a hammer drill to be able to drill holes through all types of masonry, stone and granite.
We have completed an article on how to drill into concrete, and also on the best masonry drill bits that are currently available.
You can use one of these bits with a normal drill, but it will be slower. It is always better to use these with a drill that has a hammer feature.
Drilling Longer or Deeper Holes in Concrete
There may be times when you need to drill a deeper hole in concrete. For those you will need a longer drill bit. These are also available as a single bit, or you can also buy those in a set.
These can get a little more expensive, so our recommendation is to just buy the size that you need.
Drilling Wider Holes In Concrete
Likewise, there could be times when you need to drill a wider hole through some type of masonry. The only effective way to do that is to use what is called a "hole saw."
This is an attachment that you put on the end of your hammer drill and into the chuck. With that you can then get through the concrete. Again these come in different sizes and you can also buy them in sets.
Best Drill Bits for Tiles & Glass
There are two different types of tiles, porcelain and granite, and these are hard wearing tough materials, but also highly brittle. Drilling through these can be difficult and there is always the added risk of cracking or damaging the tile.
A special type of drill bit is required for those. It is one with a carbon tungsten tip, which essentially makes the drill tip harder, and that allows it to get through the tough exterior coating of the tile.
There is not a great deal of use for drilling deeper holes, as the normal tungsten drill bit will allow you to drill holes for putting up bathroom mirrors, shelves etc.
Many manufacturers now sell harder diamond tipped bits, and these do last longer and drill faster.
Drilling Larger Holes Through Tiles
These are usually one off jobs and these bits are only used for waste pipes or for bathroom exhaust fan types, where you are trying to get a hole from inside the bathroom to the outside.
You can buy these larger bits in a set. They cost anything between $12-25 depending on the number of pieces in the set, and the brand that you decide to go for.
Best Drill Bits for Metal & Plastic
I am sure that you appreciate, there are many different types of metal, steel and plastic. Thankfully though most home owners never have to worry about drilling through metals.
That is more specialist work for the various trades like electricians, and also for engineering companies and industries involved in metal work
The type of drill bits for metal vary quite a lot. The standard bit for most metals is known as the "twist drill bit."
You can normally identify these as they are often either silver or black in colour as shown in the image above.
The Step Bit - Used for Wider Holes and Deburring
This is one of my favorite bits and it has so many uses. It isn't that popular though as many people don't know about them, or have never used them. As you can see from the image, these are almost always coated with titanium, and look like a cone shape.
These are used for drilling different width holes in light metal or plastic. Some woodworkers use this drill bit to make countersunk holes.
The beauty of these is that if you own just one bit, then you can make a variety of different diameter sized holes.
Best Drill Bits for Wood
Like metal there are different types of wood. Primarily though these break down into two main types, soft wood or hard wood. Soft woods include cedar, pine, redwood and spruce and come from coniferous trees.
These are used for cheaper furniture, doors, bedroom furniture and general woodwork like cupboards, shelves and roofs.
The hard woods include ash, beech, elm, mahogany and oak, and come from deciduous trees. These are used for wooden ladders, quality furniture and some interior woodwork.
Drilling through soft woods is much easier that drilling through the harder woods. Most people will likely be trying to drill through the softer woods, and a normal brad point drill bit will do the job nicely.
Again you can buy these as individual drill bits, but more commonly a set of drill bits in a variety of sizes.
Drilling Deeper Holes In Wood
There will be sometimes when you need to drill deeper holes in wood, and like the other drill bit types, these do come in longer styles. Again we would recommend that you just buy an individual bit.
Drilling Wider Holes In Wood
Joiners and carpenters and those working on cabinets, kitchens and general woodworking will often have to drill wider holes. There are actually 4 different types of bits for doing this.
1. Spade Drill Bits
In the main a spade bit (paddle bit) pictured above is usually the most popular option.
Hobbyists will also drill these holes for holding candles etc. Once again they can be bought as an individual size, but you will get better value from buying a set of these bits.
These are ok for rougher work like general construction work, but they do not leave the neatest of finishes. They are also quite jerky and rough to use, but they will drill out wider holes. They have a point though, and that can push through, and you may not want that.
These are available in a range of sizes and a typical set will include sizes from 3/8" to 1.5 " These sets normally cost around $10 on the low end and around $25 at the higher end.
2, Forstner Bits
There are also Forstner bits and these are used for finer woodworking, as they make a much neater and flatter wide hole. They are more expensive, but they leave a nice flat smooth hole, so a much neater job.
In a set you will be able to get sizes ranging from about 1/4" to 2". The price can vary from around $15 on the low end to $60 for the very high quality ones.
3. Hole Saw
I always calls these the frightening bits as they just have that look to them. They are used for really large holes on things like cable routes, and door hardware. These are also used by electricians and plumbers.
They have a drill bit in the centre which is used to align the hole, and then a large circumference set of teeth, which do the cutting of the larger hole.
If you are going to be using one of these for the first time, always try it out on an old piece of wood first, as these take a little bit of time to get used to.
At the lower end these will cost around $15 for a hole saw kit, that will include a number of sizes, along with mandrels(used for quick changing) and a case.
4. The Step Bit
I mentioned the step bit earlier and mainly those are used for metal. They can also be used for wood, and some carpenters will use these for making countersunk holes.
These are used as the name would suggest to drill a hole, and allow a countersink at the top. That then allows a screw head to be neatly fitted into the hole that it leaves.
As you can see from the image above, these drill a hole, and then at a certain pint, the burrs on the sloped countersink carve out a round sloped curve into the wood.
Video Showing Actual Drill Bits and Their Applications
Here is a useful video which last just under eight minutes. The most popular drill bit options are shown and discussed here. It is certainly worth a watch, if you have the time to do so.
Auger Drill Bits
These are used, almost exclusively by cabinet makers and carpenters to make large and deep accurate holes in wood. These have a very fine point usually made from carbon steel, which are easier to sharpen.
They have a very distinctive spiral style shaft.
Brad Tip Point Drill Bits
These are designed for drilling through wood, and they have a point that allows you to very accurately find the centre of a hole. When positioned the point then drills a small pilot hole, and that allows you to push the drill quickly and easily through the wood.
High Speed Steel (HSS) Drill Bits
You will always see a lot of reference to these HSS steel drill bits. Why would you consider buying those. These are designed to be able to drill up to 40% faster than a normal drill bit.
They also do not heat up as much, and as such they have a longer lifetime. These HSS bits can also be covered by a variety of materials such as black oxide, cobalt, titanium and diamond.
The purpose of the coating is to further increase the hardness of the bit, and also how long they will last.
Titanium Coated Drill Bits
Some drill bits come coated with Titanium. That simply means that bits covered with this material stay sharper for a longer period of time. These are ideal for professionals and serious DIY people, who want to use a bit on a regular basis, without either having to replace it, or get a new one.
These also do not heat up as much as a regular drill bit. These can be used to drill wood, metal, plastic, fibre glass and PVC.
Twist Drill Bits
These are what are known as the "general purpose drill bits, and can be used to drill into most materials like plastic, fibre glass and wood. You can buy these with special coatings on them that make them more durable and tough.