Torque and speed
|A cordless screwdriver is operated using the speed control trigger. Squeezing the trigger allows power to flow from the motor to the chuck. The motor’s power is divided between torque and speed, so the two have an inverse relationship (meaning that when one increases, the other decreases and visa versa).
|Pulling the trigger starts the chuck turning. The further you pull the trigger in, the faster the screwdriver will go, but the less torque it will deliver.
|The more you release the trigger, the slower the screwdriver will go, but the more torque it will deliver. Generally, work with tougher materials or larger screws should be done at slower speeds as it requires more torque.
So what should I look for?
A cordless screwdriver with a higher level of torque will be able to drive larger screws into tougher materials.
|However, the more torque a tool has, the more expensive it is likely to be.