On 2012-02-09, Bruce L. Bergman (munged human readable) wrote:
On Thu, 09 Feb 2012 10:56:24 -0600, Ignoramus13761
wrote:

Bruce, what you offer is a well written generic safety message. "be
careful modifying things and also, when lifted, things might fall, and
if you stand under things that fall, they will fall on you, and you
need a lot of expensive doodads and well paid engineers to be OSHA
compliant".

It is hard to argue with this.

What Roger is trying, though, is NOT overhead lifting, and he is just
trying to get stuff out of his pickup truck.

Oh, it's not "Overhead Lifting", is it?

Nope.

What color is the Sun on your home planet?

Do you have an engine hoist like this, Iggy? Good! Now go out back,
remove the tailgate on your pickup and set up the engine hoist just
like you would if you were going to pick an engine block out of the
back of your pickup truck.

Take the pump handle, insert it in the jack pump socket, and grab hold
of the pump handle on the lifting ram like you're lifting the load...

Quick Quiz: B WHERE THE F*** ARE YOU STANDING?? /B

To the side.

Your arm is within a foot of that boom - your head and body, two feet
max. Unless you modify it with an Air-Over-Hydraulic jack, and then
you can back off maybe 3' or 4' - any more and you can't keep control
of the load.

Yes, it's not technically "Overhead" lifting - but for purposes of
operational safety it might as well be.

No, it is not.

Remember, you might have only been lifting 1 ton, but there's a
reason the Jack on the engine hoist is rated at 8 Tons or more -
Leverage. Lots of it, and in several directions.

Actually, not a ton, just 1,000 lbs.

If that engine hoist chose that moment to come apart, all the pieces
that break and had a ton of load and up to 8 tons of force applied on
them are going to shoot off in various and unpredictable directions.

Little things like the main arm hinge bolt that sheared off can have
killing velocities for a few feet and can embed in a wall up to about
10' to 20' away. And the hoist arm and upright have more than enough
mass + velocity to break an arm, or a leg, or shatter your skull.

I do not see, how the bolt can get sheared by that sheetmetal.

The load is most likely going straight DOWN - but it can bounce, roll,
slide or do other unpredictable things when it gets to another hard
surface, and if the lifting arm is partially intact it could influence
the load into swinging down in an arc... And any limb that gets in
the way (or portion thereof) is getting crushed.

It is not that unpredictable and not nearly as violent. It would just
come down at a few feet per second max.

Don't pooh-pooh this - it's serious ****.

And you don't want it anywhere near the fan, when it hits you'll know.

-- Bruce --

I am not agreeing with what Roger wants to do, for other reasons, but
if the crane is used properly, its failure would have mild
consequences.