[SML] Rigging calculation question...

[Jason C]

Thank you all for your responses.  I will say that I agree that rigging is
a dangerous field to not know what you are doing... Which is why I would
never ever claim to be a rigger and I certainly try not to let anyone
mistakenly believe that I know what I am talking about.

That being said,  when there is the choice of me doing the best I can to
get the right gear in place, and staying quiet cause "that's not my job", I
have to err on the side of doing something rather than there being no
oversight at all on the rigging of the wall.

I'm sure some of you would love to argue (though you probably wouldn't have
to argue that hard) that is insane for a company to be hanging those kinds
of weights without passing it through a qualified rigger or structural
engineer.  And for the most part, you are right, but, it's the situation I
find myself in now... And it's not even my department.  Just that old
problem that ld's are magically expected to know how to calculate loads.

I do what reading and research I can, but in this instance, I could not
find solid and *comprehensible* answers which is why I turned to the list.
I, through my career, have always seen the way more than qualified
membership of this list as an invaluable resource of some of the top
professionals in the world... Which is why it's a little odd to get chided
for coming to the list for help.  If I had personal relationships with
people like Mr. Sapsis, Mr. Hall, Mr. Vick, or the myriad of others on this
list, I would have called them personally for help.    But since I don't, I
use the best way that I know how.

Anyways, thanks again though for those of you who provided links and advice
on how to proceed.  I am still a bit confused as to how far to go and on
what direction though.  It sounds like getting a highly accurate load calc
is very difficult, so I guess the question is less about knowing exactly
how much is on each motor, and more about getting a close enough
calculation to know what kind of hardware to use... 1T vs. 2T motors, 5/8"
shackles or 3/4", 3/8" steel vs 1/2"?   I really do like the idea of load
cells, and will definitely push them as essential, but all the cells in the
world won't do you a lick of good of you show up on site with the wrong
hardware and I guess that's what I am trying to figure out.

>From the responses, it sounds like doing a 4 point spread calc is much more
appropriate than the 6 point, but is it good enough? What if the load is
not centered how would that effect the relationship of the motors in the
system?

Again, thank you all for your responses.  I truly appreciate you all being
available as a resource for those of us struggling through this journey!
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