On Wed, 18 Mar 2009 08:57:36 -0500, Tim Wescott
wrote:

On Wed, 18 Mar 2009 11:57:21 +0000, _ wrote:

One of the projects involves both re-doing the garage and lifting a ford
4-cyl motor out of a car. There's a fellow selling an I-beam locally,
13 feet long, 8 inches deep, 4 inches wide (no web thickness specified).
This would span the garage nicely - could I rely on it to not bend if I
hook up a hoist to the centre and lift that motor? Supported on the
ends only...

There are engineering tables for that sort of thing. I don't know where
the right place to look is, but that's all been reduced to "look it up
and run a couple of numbers".

The tables are in the AISC Steel Construction Manual, but first you
need to know which table or chart to use and how to apply it
appropriately. There's lots of jargon and abbreviations in the data
that the user needs to interpret and then determine whether any of it
is relevant to the case at hand.

For example, the charts and tables assume a factor of safety for
structural applications which is much lower than the practice for
overhead lifting.


As Lloyd pointed out, mount that sucker so it absolutely positively
cannot turn on it's side or fall off of it's supports.

That's a good start. g

--
Ned Simmons