No, engineering texts say that "I" or "T" sections have the greatest
rigidity *in a defined plane*.


Nav wrote:
Yes that's what I said ealier!

It's not what you said just then.... you seem to be able to lose track
of this sort of detail.

Is there a difference between "rigidity" and "rigidity in a defined plane"?


.... What is it with your inability to read?

What is it with your inability to understand a simple concept?

Anyway, now you know a triangle section isn't _always_ the strongest for
a given amount of material.

Yes it is, unless you limit the forces applied to a single plane.

... You must be so happy to have learnt
something new! Hooray!

Careful with the fireworks, Navvie.


The compression force on the boom is the cosine of what angle?


No, no, you silly man you need to re-read your posts. It was _you_ who
keeps saying it's a cosine -not me!

Are you saying it's definitely not? Are you sure?

Fresh Breezes- Doug King

Nav wrote:
Well, compare the numbers for a pipe and box section and you will se my
14% rule of thumb...

Do you suppose there might be a scale effect?

Do you know what that is?

DSK

haha Down in W.Chester, the boss informed the shop guys they weren't
getting over time any more, next day they left a job 3/4 done and went
home. OT is back on the books.

Scotty


"Scout" wrote in message
...
Is it still safe to 'supervise' in Canada? Mr. Bush says it's better
for the
little guy if you get paid 5/8's while working the 7/12's (as the
word
'supervisor' is attached). What a bone head, what an enemy of the
working
man..
Scout

"Capt. Mooron" wrote in message
...
Wish I could get time to take off myself.... I'm waiting to see
if they
go
ahead with a planned project for me to supervise. It's 2 months
of 7/12s
but they have a strike to contend with.

CM




"Scott Vernon" wrote in message Maybe
take a few
days off and go sailing. Sound good?
|
| Scotty
|
|
| "Capt. Mooron" wrote in message
| ...
|
| "Scott Vernon" wrote in message
|
| | poetic license? is that a fancy way of back pedaling?
|
| Absolutely not..... I never backpedal going downhill.
|
| CM
|
|
|
|
|
|

Quiet Doug. People who understand engineering are talking.

Cheers

DSK wrote:
Nav wrote:

Well, compare the numbers for a pipe and box section and you will se
my 14% rule of thumb...


Do you suppose there might be a scale effect?

Do you know what that is?

DSK

Nav wrote:
Quiet Doug. People who understand engineering are talking.

In other words, you have no clue. Again.

If one could get the Imm of a section by using simple multiplication on
the result of another different section, then why would anyone ever use
calculus? Why all the fancy symbols and stuff?

Oh wait, I know... to impress superstitious fools like you.

You can't even identify all the forces on a simple free body diagram.

DSK

DSK wrote:

Nav wrote:

Quiet Doug. People who understand engineering are talking.


In other words, you have no clue. Again.

If one could get the Imm of a section by using simple multiplication on
the result of another different section, then why would anyone ever use
calculus? Why all the fancy symbols and stuff?


A trained enginer knows that moment of interia scales scales between
shapes with same geometric peoperties such as in this case, width,
height and wall thickness. Perhaps you should look at the equations for
inertias of elipse, circle and boxe sections and then you will see why
my rule of thumb is not only corrrect but very useful? It's a pity that
you have such trouble with such freshman engineering.

Cheers