On Mon, 13 Nov 2006 15:38:50 UTC, mike wrote:

I think because you apply the wist at the same time as you wallop the bit
into the head.

There hasn't been much my impact driver won't shift.!

Incidentally is the impact driver the correct name - it seems also to be
used for the air and electric ones?

Yes. In fact, these tools were known by that name long before the air
and electric ones, AFAIK. There was an extensive discussion on the topic
here, a while ago. As apart of that discussion, I produced a picture of
my ancient one...it's still there...

http://www.tavi.co.uk/impact.jpg

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