On Mon, 18 May 2009 22:13:38 -0500, "Martin H. Eastburn"
wrote:

Put a 1/4" bead down the line - with a bead bender. It will strengthen
the side very well.

Martin

Indeed it will. However if the bead gets flattened out...

Gunner


Gunner Asch wrote:
On Mon, 18 May 2009 11:59:48 -0700 (PDT), whit3rd
wrote:

On May 17, 3:36 pm, "Karl Townsend"
wrote:
We're building a water tank 16" high by 6' by
10'. Our question, how thick a steel do we need to prevent the water
pressure from severely deforming the tank. The main issue is, of course, the
bottom and it would be no big deal to put in a reinforcing angle iron every
two feet.
The total weight of water bears on the bottom of the tank; you need to
support
that bottom, probably every foot or so, to keep it from warping. Any
thickness
that has been suggested is 'enough' with suitable support. If you
set it
on level ground, it can be a kid's vinyl playpool.

Your more significant problem is the 10' long straight sidewall, which
will
be bowed outward by water pressure; at 16", that pressure is
rho * g * h = 62*(12**-3) *16 = 0.54 pounds/square inch
The bottom of the sidewall, of course, is welded to a stressed sheet,
and that will take about half of the force, the other half is

10 ft * 12 in/ft * 16 in * 0.25 * 0.54 psi = 259 lbs

None of the suggested sheet thicknesses will hold 259 lbs distributed
load without deflecting on a 10' length. You need to put a rigid
brace (something
like a 2x6 or so) at maybe 8" from the bottom, to keep the sides
straight.

Indeed. Id suggest one at the top as well.

Gunner

"Lenin called them "useful idiots," those people living in
liberal democracies who by giving moral and material support
to a totalitarian ideology in effect were braiding the rope that
would hang them. Why people who enjoyed freedom and prosperity worked
passionately to destroy both is a fascinating question, one still with us
today. Now the useful idiots can be found in the chorus of appeasement,
reflexive anti-Americanism, and sentimental idealism trying to inhibit
the necessary responses to another freedom-hating ideology, radical Islam"

Bruce C. Thornton, a professor of Classics at American University of Cal State Fresno

"Lenin called them "useful idiots," those people living in
liberal democracies who by giving moral and material support
to a totalitarian ideology in effect were braiding the rope that
would hang them. Why people who enjoyed freedom and prosperity worked
passionately to destroy both is a fascinating question, one still with us
today. Now the useful idiots can be found in the chorus of appeasement,
reflexive anti-Americanism, and sentimental idealism trying to inhibit
the necessary responses to another freedom-hating ideology, radical Islam"

Bruce C. Thornton, a professor of Classics at American University of Cal State Fresno