My two most necessary screwdrivers are both about 35 cm long. Length is important for delivering maximum torque and 35 cm is about the optimum: beyond that it’s often difficult to maintain contact with the screw head.Two other features are vital. The handle must be 100 per cent grippable and it’s surprising how many aren’t, usually because they can’t accommodate the whole of your hand. The other is the tip of the shaft, of which more later.
The conventional (yellow handle) screwdriver dates back to 1972. We’d just bought our first British house and were faced with installing hundreds of Rawlplugs. Screwing into Rawlplugs sometimes requires enormous force, especially if the hole in the wall is slightly too narrow. This rather brutal driver sometimes appeared too big for the job but only if you worried about aesthetics. Its dimensions ensured that the tip could be squared off (instead of tapering like a chisel) to give maximum tight contact with the screw slot.
The blue-handle Pozidrive screwdriver cost what was then an eye-watering £10 but once I’d got over that I was well satisfied. Cheap cross-head tips quickly wear and the driver must be thrown away. This one has survived 35 years and still engages sweetly. But its unique quality relates to its thin shaft. I may be deluding myself but the shaft seems to twist very slightly when force is applied, tightening the contact with the screw. As a result it rarely disengages accidentally. An old blogger’s tale?
2 comments:
You were, I recall, never a man to use a ratchet screw driver. The extra leverage provided by the ratchet mechanism, you believed to be an uneccessary complication, and though you were too polite to say it, was only for wimps like me.
I reckon the ratchet screwdriver is the best tool in my kit. It is made by Snap on Tools who supply to professional vehicle mechanics and was given to me by my son who is the race mechanic for a motor cycle racing team. You can put any kind of bit into it (Posi Drive, Philips or cross head, or Allen Key) which gives you the option of using normal quality bits and replacing them as required or using expensive long lasting ones.
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