On Sat, 20 Nov 2004 10:58:08 -0600, Wayne Cook
vaguely proposed a theory
.......and in reply I say!:

remove ns from my header address to reply via email

I'd be willing to bet that everyone who's had problems with impact
wrenches haven't read the instructions. The fact is 1/2" impact
wrenches really need a 1/2" hose and large size quick connects to get
enough air to make rated torque at rated pressure. If you want rated
torque with a 1/4" or 3/8" hose then you'll have to run at higher
pressure to make up for the pressure drop.

Yes. I agree. And guilty as charged, although I kept my run as short
as I could, and even tried running two 3/8 pipes in parallel (which I
have since found to be a minimal gain). What you need is a gauge at
the tool end, probably.

Having since looked at fluid flow through pipes, I have been
completely floored by the effect that pipe size has on flow
capabilities. Going from 3/8 to 1/2 over a 20 foot length causes a
about 4:1 reduction in flow restriction. This is the fifth power of
the diameter ratio!

When I was looking at this "off the top of my head", I assumed it may
be the square of the diameter, maybe, "plus a bit". But friction on
the walls causes more restriction than the actual area AFAICS!


Also not all impact wrenches are made for max torque.

Here I have more trouble agreeing. If it says 350lbft, then it should
do 350lbft, whatever the usage it's then not suitable for.