Using the table
Overall score is made up of:
- Performance: 70%
- Ease of use: 30%
Performance score consists of:
- Battery life: 50%
- Torque: 50%
Ease of use score consists of the following equally weighted components:
- Operating the controls.
- Price Recommended retail, as of July 2009. It pays to shop around; we paid much less than RRP for some models.
(A) Discontinued but may still be available in some shops. Replaced by GSR18V-LI model with Li-ion battery.
(B) Model number CLK18/2001 refers to the kit including drill, charger and torch; the drill’s model number is LDD1802. Replaced in August 2009 by new model LCD18022D with more compact battery pack (1.4Ah - the tested model's battery is 2.4Ah so battery life may not be the same).
ns Not stated.
How we test
Battery life First, our tester, Josh Giumelli of Kondinin Group, conditions each battery by fully charging and discharging it three times. He then fits each drill with a new 13mm spade bit and drills holes at slow speed through 50mm-thick dry jarrah timber, counting the number of holes achieved with one battery charge. Dry jarrah is very hard so this is a tough test. The best performer in this test was the AEG which managed 55 holes; the worst was the Makita, with just 8.5 holes. The battery is recharged and the test repeated at fast drilling speed. The best performer in this test was the Ryobi with 105.5 holes; the worst was again the Makita with 32.25. Then, after another recharge, he counts the number of 50mm tek screws (self-drilling screws that need no pilot hole) he can drive into 100mm dry jarrah. Again, the Ryobi was best in this test, managing 125 screws; the worst was the Ozito with 19.5.
Torque Each drill is mounted in a dynamometer to measure its stall torque. This is the rotational force at which the drill stops turning; the higher the torque the better. The AEG scored best with 40.46 Newton metres (Nm); the worst was the Ozito, with 17.05Nm.
Ease of use
The drills are assessed by four users, including a female left-hander, who rate them for comfort and balance while drilling holes and driving screws, both horizontally and vertically. They also assess the controls.