"Dave Plowman (News)" wrote:
In article ,
Ian Stirling wrote:
It depends - gearboxes can make the thing a fair bit heavier, and are
not really required if the drill also supports a speed limiter on the
trigger (as 99% of variable speed drills do).
(Unless you're doing BIG screws into hard wood.)

A mains drill already has a gearbox, since the armature speed is approx
20,000 rpm. And single speed drills are usually designed to give about
2500 rpm before electronic control. To give a say 600 watt drill decent
slow speed torque for screwdriving this basic speed needs to be under 1000
rpm. But that might make the drill rather restricted for general use.

IME, anything 75mm or under will go into almost any wood, just fine with
a 'One speed' drill. A bit over that, and you may need to use a dab of
grease.
A bit over that, and it won't put it all thej way in.