The speed is usually controlled by a trigger, the further it is pulled back, the faster the speed of the drill. One step up again offers variable speed control where the speed is infinitely variable up to a pre-set limit. The switch between speeds may be electronically or mechanically (by changing the gearbox ratio). One step up from single speed drills are those offering fixed speeds, generally two, which are selected by the operator, the slower speed being about 500rpm less than the fast speed. Single speed drills (2000/2500rpm) are available but lack versatility. They can also put a lot of strain on the motor as it usually runs fast to compensate for its lack of power. Larger bits need to turn slower than smaller bits otherwise they may overheat and lose their cutting edge. The ideal speed of a drill bit depends upon the size of the bit and the material being drilled. It is a distinct advantage to have at least one replaceable battery pack.ĭifferent types of battery are used on different models, the two common types being: Most diy models have battery pack from 9.6 to 16 volts, while some with up to 32 volts are aimed at the professional user. In simple terms, the more you intend to use a drill, the higher the input wattage should be.Ĭordless drills are generally rated by voltage, the higher the figure, the more powerful. while a higher wattage tool will work less hard to do the same job, with a consequent reduction in wear and tear. The wattage should normally reflect the robustness of the wholeĭrill, a drill with higher should have more robust bearings and gearbox etc.Ī low wattage drill used hard will be working at maximum power all the time working its bearings etc. Most diy models are in the range 500 to 1000 W. With corded electric drills, power is normally quoted as wattage in the UK (horsepower in the USA), the higher the wattage, Even then, most models have replaceable battery packsĪnd having a spare, fully charged, battery pack will enable the electric drill to come back to life.

Is that they can be used almost anywhere until the battery pack is exhausted. Except for the smallest ones, they do tend to be too bulky to use as simple screw drivers.Įlectric drills have made great advances in recent years and can have similar performance to most corded drills. Of a socket, it's just a case of 'plug it in and start drilling').Ĭorded drills tend to be more powerful and have higher speeds than cordless electric drills. The distance you can work from an electric socket (although a suitable extension can be used) but where you are working in range

Screwdriver function - torque control and reverse function Įlectric drills have a dangling lead (with plug attached) which needs to be plugged into an electrical supply.Modern electric drills have a variety of 'bells and whistles' which can be confusing to anyone An electric drill must be the most common power tool owned and used by the diy person and is probably the first electric

Electric power drill