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Sevenhundred Elves

willshak wrote:

on 9/16/2007 10:23 PM Sevenhundred Elves said the following:
wrote:

Bob Ward wrote:

On Sun, 16 Sep 2007 11:23:44 GMT, "Jerry Foster"
wrote:

The chairs were put away and I haven't been able to bring myself to
trust any kind of holder since then, alas.

Jeannie

I don't know the geometry of your chairs, but, in the case of a simple
hammock, the tension on the supports greatly exceeds the weight of
the person in the hammock. How greatly depends on how much the
hammock is allowed to sag.

Jerry

I question your geometry.

I question your trigonometry.

Especially on a simple hammock, where the design requires TWO points
of support. No way can you DOUBLE the user's weight by any kind of
angle trickery.

What is the tangent of 90 degrees?

Xho

Maybe you should explain what kind of hammock you mean. I think I know
what you're getting at, and what the misunderstanding is.

Below is my idea of a hammock. In this type of hammock the fasteners are
attached to the beam. The only force on the fasteners is what is
necessary to hold up the seat and its occupants. (ASCII art,
non-proportional font required for viewing)

_____.___________________________________._____
|_____|___________________________________|_____| -- Beam
|| 0-- Fastener 0 ||
|| | | ||
|| | | ||
|| | | ||--Support
|| | | ||
|| | | ||
|| | | ||
|| |-- Chain | ||
|| | | ||
|| | | ||
|| | | ||
|| | _________________________________ | ||
|| |/ \| ||
|| | | ||
|| | | ||
|| | Backrest | ||
|| | | ||
|| | | ||
|| | _________________________________ | ||
|| |´ `| ||
|| | Seat | ||
|| |___________________________________| ||
|| ||
|| ||
|| ||
|| ||
\\// -- Grass \\//

But I believe you were thinking about something like what I've shown
below. In this type of hammock the force on the fasteners easily exceeds
the weight of the seat with occupants, because of the geometry, just
like you say.

| | | |
| | Fastener Chain | |
|___| / v |___|
|____}------,-----------------------------------,------{____|
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |--Support
| | |-- Chain | | |
| | | | | |
| | | | | |
| | | | | |
| | | | | |
| | | _________________________________ | | |
| | |/ \| | |
| | | | | |
| | | Backrest | | |
| | | | | |
| | | | | |
| | | _________________________________ | | |
| | |´ `| | |
| | | Seat | | |
| | |___________________________________| | |
| | | |
| | | |
| | | |
| | | |
\\||// \\|||//

This should neatly reconcile your different opinions, I hope.

S.

Very nice ASCII art. However, my idea of a hammock is different. To me,
a hammock is for napping in the back yard when you should be doing
something that the SWMBO has told you to do. Usually strung between two
trees, but some come with frames for hanging.

Ah, yes, I forgot that these are also called Hammocks in English. Sorry
about that. They have a different name in Swedish, literally translated
it would be "hanging carpet" (hängmatta). But the things I depicted
above are for some reason called hammock in Swedish. We simply borrowed
the English word, I guess. Anyway, the kind of hammock you mean would
also be afflicted by the geometric issue.

S.