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Woodworking Drill Bit Guide – Finding the Best Bit for the Job

NOTE: This article is my opinion taken from my experience. This article uses sponsored links.

Where do all the different types of drill bits come into woodworking?

And do you need them all?

The short answer is no. Here’s what i’ve learnt from my 15+ years experience with drill bits.

Metal drill bit

At a glance:
Size hole:1mm – 12mm (1/8 to 1/2 inches)
Price:$$ (Check here)
Neat hole guide:☆☆☆☆ (neat – minimal tearing)
Sharpening:Can do yourself with grinding wheel
Mess:Not a lot depending on size of hole
Quick change shank available:Yes
Best suited:– Small holes in Wood
– All round drilling

These ‘twist’ bits are the drill bits I use 95% of the time. They are easy to use, come in good size sets and can be sharpened pretty easily.

Wikipedia says that the angle is 118° however I don’t change the angle, I just clean them up when sharpening. I was taught in trade school, the less you do, the better.

I also don’t really worry about the coating. The drill bits I have (see images) coated in titanium nitride (yellow – see images). All the coatings are designed to extend tool life but I typically buy on price to be honest.

The main thing with drill bits is the steel that they are made from. Better quality steel will last longer. But it’s hard to compare this from different manufacturers.

Branded tools like Sutton, Alpha and Irwin have served me.

The only time I had an issue with drill bits is when I bought a couple of hex shank sets on eBay (no brand) and they were rubbish out of the box.

Another tip is it helps to keep a good full set somewhere, that way you can always drill the right size hole and don’t get stuck during a job. I have a green Sutton set at work and an Alpha set at home.

Final word:

Buy and use brand names here as they get used a lot. Here’s a good place to start for a full set and here’s what I keep in my office to replace broken bits.

Once you get a good set, you can replace bits individually. A good drill bit set is a good thing to ask for as a present (Birthday, Christmas, etc.).

Video

A close up of drilling a range or different drill bits

Wood drill bits (Brad point)

At a glance:
Size hole:2mm – 13mm (1/8 to 1/2 inches)
Price:$$$ (Check here)
Neat hole guide:☆☆☆☆☆ (Very neat – no tearing or wandering)
Sharpening:Hard but doable
Mess:Not a lot depending on size of hole
Quick change shank available:Yes… but not recommended
Best suited:– Precise small holes in Wood
– Repetitive drilling jobs

Perfect for drilling wood the tip centres the bit to exactly how it should be.

The downside is that these are harder to sharpen than a standard metal bit.

You can get sets of wood bits in a hex shank quick change for your impact driver although I don’t recommend them. The accuracy (which is the biggest benefit of the wood drill bit profile) is gone because the slight looseness of hte quickchange chuck causes the bit to wobble when spinning.

I do keep some wood bits and use them mostly on the pedestal drill to help students who are drilling repetitive holes. The tip on the wood drill bit removes the need for the bradawl, effectively removing a step and making the process faster.

Personally, in my workshop I use metal drill bits mostly because they come in large sets (metric and imperial) and are easier to sharpen.

Final word

Great to have in the workshop for those occasions where they are better than metal bits, but not 100% necessary. I learned while writing this that you can get specialist larger than 13mm brad tips as well, but for larger than 13mm I like to use a Forstner bit.

Forstner bits

At a glance
Size hole:6mm – 76mm (1/4 to 3 inches)
Price:$$$$ (Check here)
Neat hole guide:☆☆☆ (Neat – some tearing)
Sharpening:Send away
Mess:A lot
Quick change shank available:Yes
Best suited:– Larger holes in wood, fast
– Boring holes (for recessing)

Forstner bits cut larger holes (up to 76mm or 3 inches that i’ve seen). The difference between them and a holesaw bit is twofold

  1. They turn the hole into shavings, so more mess but you don’t need to take the left over material out of the bit each time which does make things faster (this is why I prefer them in my high school workshop)
  2. Forstner bits only cut wood, not steel. Holesaw bits will cut more materials such as some metals.
  3. Forstner bits will bore holes and leave a flat bottom. Holesaw bits cannot do this.

I like Forstner bits. They give a pretty good hole and they don’t jut around because of their sturdy design.

On the negative side, you can get some smoke from them when in use due to the friction created by the hot spinning bit and the material so they do need to be semi-regularly sharpened.

Final word

You don’t need these (you can use holesaws to drill large holes), but they suit me perfectly in the workshop. They don’t need to be cleaned out after every hole and they are also the best option for boring holes.

You can buy them individually as you need them, but there are also set’s available. Do not buy cheap ones!

Holesaw bits

At a glance
Size hole:6mm – 121mm (1/4 to 4 49/64 inches)
Price:$$$$$ (Check here)
Neat hole guide:☆☆ (Some tearing)
Sharpening:Send away
Mess:A little
Quick change shank available:No
Best suited:– Larger holes in wood
– Cutting discs or wheels

Holesaw bits can get quite big. 121mm (4 and 49/64 inches) is the largest ive seen but there could be larger. Holesaws keep the hole section which is the difference between them and the forstner bit.

I tend to use Forstner bits in the high school workshop becasue holesaw bits get hot and getting kids to take out the ‘hole’ in the holesaw bit takes time. It’s easier for them to clean up their mess.

But hole saws are tougher. These ones (which is the style that I have) can take some beating and even a nail or two in case you decide to remodel your kitchen.

You can get holesaw bits with tungsten teeth. I advise you to stay away from them! If you hit a nail, they are broken. If the tungsten comes off, it is broken. The bi-metal holesaw bits are much better, and last a lot longer.

Final word

Buy good quality here. There are cheaper versions available that use different methods, with different thicknesses of holesaw cutters. They are crap.

Better off with a smaller range of bits than a cheaper set. Although a good set like this does make a good christmas/birthday present for someone that doesn’t know what to buy you.

I’ve never bought an individual holesaw although it seems you can (see here). Having a set gives peace of mind. If you do want to try and buy individual you’ll need one with an individual arbor with pins like this. Don’t buy ones that work any other way!

Spade Bits

At a glance
Size hole:6mm – 50mm (1/4 to 2 inches)
Price:$$ (Check here)
Neat hole guide:☆ (Expect tearing)
Sharpening:Can do yourself
Mess:A lot
Quick change shank available:Yes
Best suited:– Medium sizes holes in wood
– Holes in hard to reach places

Spade bits are great if you just want a hole in something. The length of the bit allows you to drill quite a deep hole, and the point does allow you to start the hole precisely.

Having said that the hole usually isn’t the cleanest hole you will ever drill. And for this reason I don’t use them much in the workshop. When I used to work in construction and go ‘on site’ a lot, the spade bits got quite a workout.

But for fine woodwork, they aren’t suited I find. They turn the hole into wood shavings like the Forstner bit but their construction means they don’t have the support at the drilling face.

Final word

Good to have around although sometimes can’t give the quality of hole required. I have a set of Irwin spade bits at home that hardly ever gets used, but it does come in handy sometimes.

Plug cutter

At a glance
Size hole:9mm – 25mm (3/8 to 1 inch)
Price:$ (Check here)
Neat hole guide:☆☆☆☆☆ (Quality – the plug)
Sharpening:Could do but better sent away
Mess:A little
Quick change shank available:No
Best suited:– Cutting small circles for projects
– Plugs for covering up screws

Plug cutters are different to all the other bits we have covered in the fact that they are concerned with the ‘plug’ not the hole that is left in the timber.

Because of this, they serve a very specific purpose. You could use them to drill holes but their sizing is measured by the size of the plug so you might find it hard to get the size hole you want.

Plugs can be used to fill screw holes for finishing (instead of putty) or for making items like toys and other fine woodworking. They are extensively used when constructing with the pocket hole method.

There are two different styles of plug cutters. Straight and tapered. A tapered plug has a slight diameter changed and is designed to make it easier to put in the hole. Straight ones are straight.

I haven’t had experience with tapered so I can’t speak to their effectiveness. But the straight ones do cut straight dowel.

Final word

Handy if you ever need plugs, but I must admit I rarely use them. If you need plugs buy the one you want individually. You can also buy a set with most sizes in it.

Specialty bits

Stepped bits

  • Stepped Rill Bit 1
  • Stepped Drill Bit 2

Some people swear by them, but I never used them personally, so I bought one.

It came in the mail (from eBay) and it works. I didn’t realise exactly how big it was. You can see in the picture in comparison with a AA battery.

They work as intended. If you do want a particular size hole then I would put it in a pedestal drill. This will privide the control you need for a precise hole.

Stepped drill bits come in a variety of different sizes. You can see more varieties here.

Countersink drill bits

For a long time people used countersink bits that look like a star pattern…

But the truth is they didn’t always work properly. They often created a ‘star’ pattern, instead of a circle. The reason being is that the star countersinks tend to chatter and jump around when spinning at speed.

But now, there are some different countersink bits available.

They look a cone with a hole in it. And because of their shape and cutting action, there is no chattering. They create perfect circles every time.

I had never used them although someone did recommend them so I bought a set

The good news is that these work a lot better than the star pattern countersink bits. Every hole I did (as long as I kept the drill relatively straight) was a circle.

As you can see in the images the hole can get clogged easily but it didn’t matter a great deal the hole was clogged or not. And they weren’t too expensive.

You can see the same sizes and coating as the ones I bought here (AUS or USA)

All in one countersinks

https://amzn.to/3hBo9ZT

These drill and countersink in one bits have been around in a while. They are a bit fiddly and in my experience need to be re-adjusted semi-regularly (because the drill bits slide in).

Their best use is drilling the same hole again and again, for example screwing on the back of a cupboard or production runs. I didn’t like them personally, even expensive ones. The constant re-adjustment was a real pain.

Kreg (Pocket Hole Screw) bit

This specialty bit is designed for the pocket hole jig. The reason for the shape is to drill a clearance hole (the large bit) and a pilot hole (the small bit) at the same time.

These bits save time and get better accuracy as only one hole needs to be drilled for each screw. They also tend to come with a little steel ring that acts as a depth stop that is put on with an allen (hex) key.

Becasue of their unique shape, they don’t really have any other function for woodworkers. They are also expensive so you wouldn’t use it for a different purpose either.

Drilling with a Kreg jig and Kreg bit

Centreing bit

https://amzn.to/39sGPs0

These spring loaded contraptions are designed to help centre holes for hardware such as drawer runners and hinges.

The idea is that the cage around the bit is the right size for your hole, and then you simply drill. With no mucking around about trying to make sure the hole is in the middle.

I don’t use them now, but when I worked in the trade I new someone who had them. They were nice to have but after a while your doing so many that your eye just gets good enough to get the middle each time.

If you are doing a lot of hinges/drawer runners then get one, just make sure you get the right size for the hole.

Drilling Tips

Use a bradawl

https://amzn.to/2D8XULk

A Bradawl isn’t a drill bit. In fact it looks like a screwdriver. The difference being Bradawls have a sharp point at the end instead of a flathead or philips head tip. They are used to make a point in your work, which helps centre the drill bit you are using.

These are particularly good with metal bits but work for any bit to help give accuracy.

I grinded down an old screwdriver into a point to make mine.

How to drill ‘straight-er’

Drilling straight isn’t as simple as drilling a hole. If you need a perfect 90° then use a pedestal drill press.

But if you don’t have one or can’t use one for a particular job, then I use a square on two angles (front and right hand side) to make sure the drill looks straight before drilling.

It can also help to have someone else (who has a technical eye) to check your drill by sight to make sure it is 90° to your work.

FAQ

The back of my hole looks ugly and the timber breaks out. How do I stop that?

To stop breakout, simply put a piece of scrap wood under or behind what you are drilling. It needs to be secure and have no gap between it and the piece you are working on.

To stop breakout with a holesaw, drill in one way until you can see the centre drill bit, and then finish your hole from the other side. This will also help you cleaning out your holesaw bit. You can do this technique too with the spade bit when you can see the centre tip coming through the other side of the timber.