From hanging a picture to installing a deck, all drills are DIY friendly. The main choice comes down to whether to go cordless or electric.
Electric drills are mains powered with a cord in the base and are for more heavy-duty use, with 500W a good entry level model.
Cordless drills are easy to use and often have two batteries plus a quick-charge power supply, with 10.8 to 18.0 volts ideal for DIYers.
Jessica Deuscher from Bosch says, ‘Using lithium-ion technology, cordless drills are powerful but compact, so you can use them anywhere. With the 18 volt systems available, it’s possible to use the same battery for a range of power tools, upping the flexibility factor.’
Using Cordless Drills
Choose the drill bit then hold the drill in one hand to grasp and twist the chuck open with the other.
Insert the drill bit and check that it remains centred while twisting the chuck closed.
Squeeze the trigger slightly to make sure the bit is spinning straight and the drill is charged.
Start drilling or driving slowly, using the variable speed control on the trigger for greater precision.
Step 1. Select the speed range
Choose low speed for more power when drilling into metal and plastic or driving screws, or high speed for drilling holes into timber surfaces.
Choose low speed for more power when drilling into metal and plastic or driving screws. Image: Stuart Scott
Step 2. Choose the clutch setting
Select a lower setting for small screws and less dense materials, such as plasterboard. Use higher torque for decking boards and the drill setting for boring holes.
Select a lower setting for small screws and less dense material. Image: Stuart Scott
Step 3. Set forward or reverse
Push the switch to control the direction of the chuck, forward for drilling and driving and reverse to remove a screw or extract the bit.
Push the switch to control the direction of the chuck. Image: Stuart Scott
Extend your run time
‘The best way to extend the run time from your lithium-ion powered cordless tools is to let the tool do the work,’ says Wayne Beckwith, national training manager for Ryobi. ‘Applying excessive pressure overworks the motor and drains the battery much faster than if you let it spin at a much lighter loading.’
Wayne recommends checking that all accessories are in good condition and you use the right one for the job. ‘Don’t use the tool for applications it wasn’t designed for, and if your drill has a gearbox, set low gear for securing screws and high gear for most drilling.’
Types of batteries
LITHIUM-ION Also called Li-ion these batteries cost more but only lose up to 5 of charge a month if not being used, so they’re ready to go on weekends. They provide constant full power right to the end of a charge. The battery is best put on the charger when it’s used 65 of its power.
NICKEL-CADMIUM Known as Ni-Cd these batteries lose about 20 power a month when not in use and take a couple of hours to charge. Their output dwindles as they run out of power but use them up fully before charging as they can be prone to memory effect, reducing their ability to reach full charge.
Prolong battery life
Li-ion batteries are lighter than nickel-cadmium, have greater longevity and run for longer without losing power but they can be damaged by overheating and excessive discharge.
To maximise the life of the battery, never run the drill until the battery is flat but instead top it up after heavy use.
Avoid working in extremes of temperature and take breaks or swap the batteries over to avoid overheating if using them a lot.
Store the battery and charger in a cool, dry place and remove the battery from the tool if it’s to be stored for a long time.
Cordless screwdrivers
Using a cordless screwdriver takes the effort out of securing screws by hand and the reverse function is for removing screws.
Ideal for working in small spaces, they’re ergonomically designed and lightweight for doing small jobs like assembling a shelf, attaching a cabinet handle or fixing a chair.
They have the least amount of power in the drill family, ranging from 2.4 to 12.0 volts but some models can drive more than 100 screws on one charge.
A cordless screwdriver is the best tool for small jobs like tightening loose screws. Image: Stuart
Using Electric Drills
Open the jaws slightly larger than the selected bit using the chuck key.
Insert the bit into the chuck just short of the bit flutes. Use the chuck key to rotate the chuck sleeve and tighten the jaws around the bit.
Switch on the power supply then squeeze the trigger switch to check the bit is spinning straight.
TIP Use the key in all three holes to ensure a firm, even pressure is exerted on the bit.
Step 1. Select the speed range
Choose low speed for more power when drilling into metal and plastic or driving screws, or high speed for drilling holes into timber surfaces.
Choose low speed for more power when drilling into metal and plastic or driving screws. Image: Stuart Scott
Select a lower setting for small screws and less dense materials, such as plasterboard. Use higher torque for decking boards and the drill setting for boring holes.
Select a lower setting for small screws and less dense materials, such as plasterboard. Image: Stuart Scott
Step 3. Select hammer or drill
Push the switch to control the direction of the chuck, forward for drilling and driving and reverse to remove a screw or extract the bit.
Push the switch to control the direction of the chuck, forward for drilling and driving and reverse to remove a screw. Image: Stuart Scott
Securing screws in timber
To prevent timber from splitting when a screw is secured, first drill a pilot hole, especially if the joint is close to an edge.
CHOOSE A SCREW long enough to hold the workpieces securely.
INSERT THE BIT that matches the diameter of the screw body or the core without the thread.
HOLD THE DRILL at right angles to the timber so the hole is straight.
POSITION THE BIT on the timber, turn on the drill and apply slight pressure to push in the bit.
SECURE THE SCREW by changing the drill bit over to a square drive or Phillips head driver bit.
TIP For holes more than 40mm, push in the bit a third of the way and bring it out slowly to remove the waste, pushing it in again to finish the hole.
Screw chart
To work out what size holes to make in softwood, divide the screw gauge by four for the pilot hole and as a rough guide halve the gauge for the clearance hole.
Making holes for screws
The trick to using screws is to first make a hole slightly smaller than the screw so it grabs the timber.
PILOT HOLE makes room for the screw to reduce the risk of splitting, leaving enough timber for the thread to grab.
CLEARANCE HOLE is made when joining timber tightly like for a butt joint, and is the same diameter as the unthreaded shank of the screw.
COUNTERSUNK HOLE is the same diameter as the screw head so it sits flush with the surface.
COMBINATION BITS make all the holes in one action but choose the size to match the screw.
SCREWS with a long thread and parallel sides need a pilot hole but tapered screws with an unthreaded shank need pilot and clearance holes.
TIP Use the screw head to check the width of a countersunk hole.
The trick to using screws is to first make a hole slightly smaller than the screw so it grabs the timber
Drilling chipboard
When drilling sheets of chipboard or plywood the bit tends to cause breakout as it goes through the underside. To avoid this, position an offcut under the workpiece before drilling to support the bit as it exits.
When drilling sheets of chipboard or plywood the bit tends to cause breakout as it goes through the underside
How to choose drill bits
Plasterboard
Both plasterboard and the timber studs behind it are relatively easy materials to drill into, requiring only a basic 10.8 to 14.4 volt drill.
THE BEST BIT to use is a twist bit, which has a conical point and a spiral shaft to remove waste. Use a diameter to match the screw gauge if securing to the studs, or an appropriate diameter for the fastener if using a hollow wall anchor such as a toggle bolt.
DRILL THE HOLE using the faster gear, if available, and select the drill setting on the torque clutch.
The best bit to use is a twist bit, which has a conical point and a spiral shaft to remove waste. Image: Thinkstock
Tiles
The bathroom and laundry often need a towel rail, mirror or soap holder attached to a tiled wall.
THE BEST BIT for the job is a carbide-tipped glass and tile bit, as normal twist bits won’t penetrate the glaze on ceramic tiles.
DRILL THE HOLE using masking tape to mark the location and prevent the bit from sliding off the mark. Switch off the hammer function and use the auxiliary handle to hold the drill with both hands, slowing down as the bit exits the back of the tile.
The best bit for the job is a carbide-tipped glass and tile bit. Image: Thinkstock
Glass
A mirror is just glass with a reflective backing, so the same method is used for drilling holes in both.
THE BEST BIT is a diamond core bit, as glass and tile bits have a tendency to grab and may leave conspicuous chips.
DRILL THE HOLE by positioning the glass flat on a piece of plywood. To stop the bit wandering, tape cardboard over the hole position and begin drilling very slowly. Remove the cardboard to finish drilling at medium speed, applying very light pressure to avoid cracking the glass.
The best bit is a diamond core bit, as glass and tile bits have a tendency to grab and may leave conspicuous chips. Image: Thinkstock
Masonry
Drilling into concrete and brick, called masonry, requires a hammer action to break the aggregate or brick, and drilling action to remove the waste.
THE BEST BIT to use is a multi-construction or masonry bit. Both feature a tungsten-carbide cutting point.
DRILL THE HOLE by selecting the hammer function and holding both handles. Use short bursts at low speed to start then drill at high speed, applying plenty of force and moving the bit in and out as you go.
Metal
The key to drilling into metal is to use low revs and cool the bit with oil.
THE BEST BIT is a HSS (high speed steel) twist bit for aluminium and steel, or a cobalt bit for stainless steel.
The best bit is a HSS (high speed steel) twist bit for aluminium and steel. Image: Thinkstock
Decking
Whether you’re using screws, nails or a hidden fastening system to secure hardwood decking boards, making pilot holes is essential.
THE BEST BIT for the job is a 2.5mm diameter twist bit for 10g decking screws.
DRILL THE HOLES with an electric drill because of the volume of work, using a cordless drill or impact driver to secure the screws. For nails, make holes one-third less than the diameter of the nail.
TIP Pilot holes aren’t required for treated pine decking.
The best bit for the job is a 2.5mm diameter twist bit for 10g decking screws
Specialised bits
SPADE BITS are traditionally large and flat with a centring point and used for drilling wide holes in timber
AUGER BITS have a single spur, radial cutting edge and spiral flute for making extra-deep holes and mortises
PLUG CUTTER BIT makes timber plugs that can then be used to conceal fasteners such as screw heads
DOWELLlING BIT has a point at the tip to prevent it moving off the mark, aligning dowel holes precisely
FORSTNER BIT makes shallow, flat-bottomed holes and has a centre spur for positioning accurately
This article originally appeared in the April 2013 issue of Australian Handyman magazine