On 26/05/17 21:31, Bill Wright wrote:
On 26/05/2017 15:36, The Peeler wrote:

Only for those who dont have a clue about the basics.

LOL! You don't have a clue at all about how you keep coming across,
eh, you
cantankerous senile old fart?

Those who resort to personal abuse demonstrate
(a) that they don't have a valid argument
(b) that they are immature
(c) that they don't wipe their bums properly.

(I might have made one of those up)

Bill
Nevertheless Bill, you are suffering from a common complaint,. you think
that the little you do know is all there is to know. Those of us who
have done this for a living and studied it at university know it aint
that simple.

The only time a structure is entirely in compression is the case of
masonry. The arch is the only solution to a structure that can span a
gap and still be only under compression.

Wood however is much better in tension than compression. Slender spars
can buckle under compression (if you have studied Euler's slender column
theory, the reasons are all there) and for that reason trees being
naturally slender things the use of timber in tension is the art of
structural carpentry.

The solution to joints in tension is pinning. And notching. And various
other techniques

http://www.basiccarpentrytechniques....oints%202.html

In essence the truss is a way to use slender spars that are short
enough between joints to not suffer Euler buckling when in compression.

A triangulated gate is just another truss. Some joints wioll be in
tension, some in compression.

If you cant make a joint that will take tension, you are not a carpenter

Of course these days you slap a metal plate over and bolt through, otr
just have a metal plate with teeth on pressed into the joint... but
there are proper ways not involving steel



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a matter of elementary environmental protection, or a search for
rational mechanisms designed to achieve a healthy environment. Yet
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