Torque? You want some f’ing torque? Get an old fashioned brace and bit driver. Your biggest problem is going to be snapping off the heads of the screws!
A longer blade feels smoother because some of the force goes into twisting the blade. This smoother feeling allows me to provide the maximum force I have available for my grip strength without fearing that I’m going to strip the skin off of my hand or lose my grip and bust a knuckle. This may or may not be the ‘efficiency’ the OP is describing.
Some screwdrivers have a ratchet hole in the top, too.
I have a 3 ft long screwdriver in both philips and flat, I also use a 3 ft 3/8 drive speed handle and extensions a lot. The simple reason is that you don’t need room for arms or hands. All you need is the narrow space that will allow the driver to fit. You have better vision with your hands and arms out of the way and are better able to grip the driver at a maximum leverage. You don’t have to bend or stretch as far to reach things either. Working at a table I prefer a 12" mainly for the clear vision reason.
Will you accept the query modified as: “Why do so many who use tools perceive a longer screwdriver to be be able to transmit more force?”
It is clear that the op is not the only one whose experience is such. A quick google gives quite a few other times this question has been asked on other sorts of fora by other tool users (usually with the same sorts of speculations as responses).
Answers seem to fall into groups focusing on the ergonomics (which muscles can get recruited and how how feet can get planted and/or grip and/or screwdriver alignment) to suggestions that not all of the force is rotational – that to some small degree some straight out leverage comes into play as the screwdriver goes slightly off exact axial orientation. To your belief that those who experience this are just imagining it.
To those who do experience it – does it happen as much no matter where the target screw is located? Horizontally above or below you versus vertically oriented in a door frame?
I have experienced the exact same phenomenon as you, OP, and I too am in agreement that there are times when I have tackled a stubborn screw that a longer screwdriver will do the job better than a shorter one. I have no cites, but I have always assumed that the difference experienced was a matter of leverage.
As far as I can tell, the effect and it’s cause has been described here well. You get better control of the alignment of the screwdriver, and you can position yourself better to get a good grip and exert maximum torgue on the handle.
when doing this you need to put your body into it and press the driver hard into the screw; if you don’t then you will tear up the screw head.
there are also offset screw drivers, tips that fit a ratchet wrench which also require the same care in use.
I don’t think there is any argument that a longer screwdriver is easier, better, more efficient (in application of effort and ease of maintaining position, so further argument of the point is, IMHO, unproductive.
I am still waiting for any kind of validation that a VERY long driver (2 feet) is “better” than a “long” driver (1 foot), all other things being equal.
No argument at all that a 9-12 inch driver is easier to use, if there’s room to do so, than a stubby or shorty.
Considering the consensus in this thread for the reasons why a longer screwdriver seems more ‘efficient’, there isn’t going be an ideal length. The location of the screw and the individual wielding the tool are going to determine the ideal length. If the OP has found a 2 footer best for him in most cases, and uses it more often as a result, that will reinforce his skill with that screwdriver and it will be more effective for him in more circumstances. Since it’s pretty rare for people to have screwdrivers available in 1inch increments from 1 to 3+ feet to figure out what is ideal, we’re all going to adjust to certain lengths from a smaller set of choices.
I think the longer screwdrivers are just bigger. Bigger handle, bigger tip, which gives you more torque. I don’t think it has anything to do with the length per se, it’s just that longer screwdrivers tend to be bigger around and provide more torque.
This is a good point. “efficient” could mean reducing any of the following things:
- The total energy (e.g. calories burned) used by the person using the screwdriver to accomplish a task.
- The strenuousness of physical exertion required. E.g. the short screwdriver requires the person to burn 3 calories by an intense muscle effort over a 30 second period, while using a long screwdriver still burns 3 calories but with easy, low-sweat movements over a period of 2 minutes.
- The time necessary to complete the task, regardless of how hard the person must work or how tired it makes them. This metric is likely to be the one that management would favor.
The OP made an unsupported claim that longer screwdrivers are more efficient, which I’m willing to let pass based on the discussion here… but he also made the specific claim that a two-footer (far larger than most people have) is “more efficient” than a one-footer and that “every craftsman knows this.”
Maybe the latter will fly over on Garage Journal or a DIY forum, but it stays challenged here until there’s some kind of objective proof.
A longer screwdriver is less stiff in torsion than a short one. With the same applied torque a longer screwdriver will have a greater twist angle and more stored elastic strain energy than the short screwdriver. When there is enough torque to overcome the static friction holding the screw in place, it will rotate slightly and the torque required to keep it rotating will drop (kinetic friction vs. static friction). With a short screwdriver, the torque will drop quickly with screw rotation angle and the screw will stop after a small amount of rotation. For a long screwdriver, the torque will drop more slowly as the screw rotates, allowing the screw to turn over a greater angle.
If you consider dynamic loading effects, the peak torque you can apply should also be greater for a long screwdriver. While ramping up to maximum torque, you reach a higher angular velocity with the long screwdriver, which gives some inertia to help overshoot the maximum torque you are capable of applying slowly.
You’re right that a longer screwdriver will have a greater twist angle (all else being equal), but I think that twisting works against you, not for you. There’ll be loss, in the form of heating the shaft, due to that twisting. Also, I’d expect a more “spongy” shaft will give you less control over the tip, and make the tip more likely to slip.
I’d expect that the trade-off for an optimal length, in terms of being easier to use, is between less of an angle of the shaft for a given hand movement, favoring a longer screwdriver, and less twisting of the shaft, favoring shorter screwdrivers.
Another thing to consider is the wobble when you’re working on a hard to turn screw. A longer tool is easier to keep aligned with the screw. Two inches of wobble on an eight inch screwdrivers is a lot more deflection than two inches of wobble on a two foot screwdriver. And the harder you’re having to turn, the more likely you are to be moving the handle around.