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How do you drill into hardwood?

DrillBits.jpgWhen drilling through hardwood, I suggest going at low speed and using cobalt drill bits they are tougher than your ordinary drill bits and are designed to go through the toughest metals. Cobalt drill bits are more heat tolerant and have excellent wear resistance.


One of the reasons your drill stops drilling is sometimes your drill bit has hit a very dense part of the wood. Another common reason is that the tip of your drill bit has deformed due to heat and is no longer catching on the timber. It is important to take a break when you've been drilling and are not making progress.


One helpful technique when drilling through hardwood is to start with a small bit to create a pilot hole for the bigger drill bit to cut into. - EricL


Couple of tricks for drilling into hardwood:


  • Pre-drill for every screw hole. This means drilling a pilot hole slightly smaller than the screw to insert the screw into. Here's some information which may be handy, you'll find the 'G' size on the screw packet. Check the screw pack for pilot hole information but as a rough guide:
    - 4G = 1.5mm pilot
    - 5 and 6G = 2.2mm pilot
    - 7 and 8G = 3mm pilot
    - 10G = 3.5mm pilot
    - 12G = 4mm pilot
    - 14G = 4.5mm pilot.


  • If your drill has a speed setting run it on the lower speed as this is higher torque, meaning more driving power. Most often 1 is slow, 2 is fast.


  • As you drill pull the the drill back out (in a straight line) every 10mm or so as the bit can become clogged and will start spinning, not cutting. Remove any material stuck in the bit with something like the tip of a screw, not your finger as it will be hot!


  • When driving the screws into the pilot holes, again, use that lower speed.


  • Check your drill is set to "drill" for the pre-drilling. When driving the screws try it on "screw" setting but old hardwood can be very grabby so you may need to use "drill" setting (if your drill has these settings). Just watch for kickback if you use drill setting for driving in screws.


  • Also try using screws that are "climacote" or similar, not galvanised. Galvanised screws tend to stick way more.

- Adam_W


I find that when putting screws into hardwood the trick is to scrape the thread of the screw through wax first. You could use slightly dampened soap, but it can cause some types of screws to rust. Bees wax gives right amount of softness and sticking I found, which you can buy as sticks, blocks or in a tin. You won't need much. - TedBear


Amassing an Audience

Personally when I'm working with any sort of wood, I use something like these: 

Forget anything like Philips or Flat head screws, the one to use is the #2 Square (Robertson) CSK head screw.

I've used these for about 20 years as an Electrician, they come in all sorts of lengths and diameters, but the head is the same.

It is the only screw that you can hold on the head of the driver when inverted, which makes it ideal for screwing things to a ceiling, like light fittings.

You can use them in an impact driver with no fear of busting the heads off of them when screwing into any sort of timber.

If it is exceptionally hard timber, use the drill I linked to above.

This gives the screw a decent chance to grip and not split the wood.



Mike T.

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