What is SDS and what's the difference between SDS & HAMMER & IMPACT?
Also, are cordless drills heavier cos of the battery? I am a female & don't want a really heavy drill but want a fairly powerful one with hammer action.
SDS stands for "Slotted Drive System" and also "Schnell Drilling System" - It is a type of drilling system and comes in the form of slots in the end of the drill bit that goes into the chuck of the drill.
This enables the drill to grip the bit much better than simply tightening a traditional chuck to grip the drill bit. This also allows the drill to produce more torque for the drill bit and produces more drilling power that also makes drilling easier.
Hammer action is a feature that allows the drill to produce a slight "hammer" on the face of the surface as it's drilling by vibrating backwards and forwards, again this can make drilling slightly easier. Most drills, either corded or cordless feature a hammer action that can be turned on or off.
Impact is different to hammer action in that instead of the back and forward vibration an impact driver produces a rotational vibration or pulse that produces very high levels of torque allowing you to screw large screws through solid pieces of timber with ease.
In terms of the weight of cordless drills, it can be said that some of the older types are quite heavy but certainly the newer, lower voltage types are much lighter without compromising on power. One such drill on the following link: http://www.diydoctor.org.uk/DIY-superst ... i-ion.html is a Milwaukee drill and we used one recently and found it to be really lightweight and although only 12 volt, it produces excellent levels of torque.