On 2010-10-18, Jim Wilkins wrote:
On Oct 18, 4:18*pm, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:
Jim Wilkins fired this volley in news:2ce79227-8037-
:

Not if the whole bag is inside the vacuum chamber.

True enough, but that's not the example he offered.
LLoyd

The original proposal:

"I am going to need a chamber that is somewhere in the order of
14X14X6
inches. If I went with a chunk of pipe, that would have to be
something like 16" diameter. The down side to this would be cost and
bulk. The more empty space inside the chanber the longer evacuation
time."

And the more surface area, the greater the force applied by the
atmosphere. Given your 14x14" dimension, that is 196 square inches, and
given an average atmospheric pressure of 14.7 psi that is 2,881 pounds
force which the walls will have to survive.

The 16" pipe would have 201.6 square inches, or 2,955 lbs on the
end plates.

I have my doubts about glued up acrylic (Plexiglas) handling
that.

Good Luck,
DoN.

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