Dear Mick and Galloot’s  past, current, and future.

>Dave, GGs
>Back when I was using a spiral ratchet screwdriver, I would often lock it in
>the extended position to shift a stubborn screw. The extra length makes a
>huge difference. I gather you get an increase in torque from the extra
>length. 

Okay guys I admit I was trying to be funny. I missed completely. 

>From: William Ghio
 >>>John Ruth shares his frustration. 
>>> 2) My pet hate is finding one of these beauties BENT because Denny Dimwit
used it to pry >>something. DOH !!!

>>I thot that was why they extended... better leverage!

>Bill, you are an echo from the past. After 50 some years of teaching people how
to use tools,
>yup I started in 7th grade shop class, my least favorite situation is when
someone spouts off >with your premise and I think, “Here we go again.”
>There have been times I used a 3 foot long screwdriver to remove or install a
screw. Never >because I needed more leverage. More reach certainly but never
leverage.
>That’s what a pipe wrench on the shank is for. 




Humor always gets me in trouble. I’ll try to explain the concept more
completely.
Torque is measured in foot/pounds or newton/meters. 
One foot/pound of torque on a bolt or screw is the rotational force applied by a
one pound weight on a one foot long lever.
One inch/pound of torque on a bolt or screw is the rotational force applied by a
one pound weight on a one inch long lever.
A screwdriver is used to rotate a screw by engaging the bit in the head of  the
screw. Gripping the handle and turning the handle around the center axis of the
shank rotates the screwdriver and the screw. Increasing the diameter of the
handle will increase the possible torque that the user is capable of applying
with the screwdriver.
Using a longer shank only extends the distance the handle is away from the head
of the screw. It has no effect on the rotational force.
If you are using the screwdriver as a chisel or to open paint cans you shouldn’t
be in this conversation.

You can access a nifty little graphic at Wikipedia that shows the concept in
color, here.
http://en.wikipedia.org/wiki/Torqu
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