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tube size
theconrodkid - 21/9/02 at 05:48 PM

Ok chaps,so a 1" square tube has a strength or resistance to bending of 1 unit,what is the strength in units of 1 1/2" or2" tube
of the same gauge?
no wild gueses please

chrisg - 21/9/02 at 08:05 PM

Um........one

No... 1,245,634,334

Er.....twelvety!!!!

(Wild enough for you john?)

I don't know BTW.

Cheers

Chris

theconrodkid - 21/9/02 at 08:21 PM

I guessed that

stephen_gusterson - 21/9/02 at 10:19 PM

quote:
Ok chaps,so a 1" square tube has a strength or resistance to bending of 1 unit,what is the strength in units of 1 1/2" or2" tube
of the same gauge?
no wild gueses please


if it were that simple, i guess there woulnt be such stuff as 'finite stress analysis'.

atb

steve

theconrodkid - 21/9/02 at 11:35 PM

can you use finite stress to power infinite improbibility drives?i know the answer to that its 42

Peteff - 22/9/02 at 11:05 AM

You want some vallium filled tubing then you won't get any stress. As for the infinite probability drive, I bought a time machine next week to check it out and it only exists in parallel universes. The time machine broke down next tuesday so I'm stuck for a day or two.

yours, Pete

theconrodkid - 22/9/02 at 11:19 AM

Dont you just hate it when that happens

Alan B - 22/9/02 at 12:46 PM

OK, first let's not confuse strength with "resistance to bending" they are different things. A material's ability to resist bending is a function of a material property (youngs modulus) and a geometric property (moment of inertia). We are talking about the same material and doing a comparison so we can ignore factor one.

For a square tube (ignoring the radiussed corners) the formula for moment of inertia (let's call it "I" and not go into any more detail )

I equals:
A to the power 4 - B to the power 4, all divided by 12

(A = the ouside dimn. B = the inside dimn.)

But the 12 is constant so we can ignore that too for comparison.

So for 1" x say 1/16"WT we have

0.414 units (again, forget what they are)

and 1.5" x 1/16"WT we have

1.488 units

and 2" x 1/16"WT we have

3.640

So compared to 1"
1.5" = 3.5 times better
2" = 8.79 times better

Hope that helps

interestedparty - 22/9/02 at 02:15 PM

Was that a guess, Alan?

John

Peteff - 22/9/02 at 04:02 PM

As quoted by Homer, " Bah, You can prove anything with facts ".

yours, Pete.

theconrodkid - 22/9/02 at 05:15 PM

Thanks Alan,at least we have someone who knows what their doin!the rest of you had better go back to school,see ya there!

chrisg - 22/9/02 at 06:00 PM

Not Twelvety then? Oh right.

Good of you to take time off from the Virus wars to give us the benefit Alan!!

(leave 'em to it, mate)

Cheers

Chris

stephen_gusterson - 22/9/02 at 06:40 PM

quote:
Not Twelvety then? Oh right.

Good of you to take time off from the Virus wars to give us the benefit Alan!!

(leave 'em to it, mate)

Cheers

Chris



just looked on tol after a couple weeks.

what a really trivial argument.

That graeme guy seems a bit short tempered in a lot of his posts over the 2 years ive been on that list.

Nice to know riots can still start up on there without me

Old minicountryman1961 has been real quiet lately


atb

steve

MrFluffy - 22/9/02 at 07:41 PM

Talking of youngs modulus, time to insert appropriately cheesy engineering joke :-

Two cats sliding down a tin roof, which one hits the floor first? the one with the lowest mu of course...

(apologies no funny u symbol..)

Alan B - 22/9/02 at 09:48 PM

quote:
....
Good of you to take time off from the Virus wars to give us the benefit Alan!!

(leave 'em to it, mate)

Cheers

Chris


You noticed me flexing my moderator muscles eh?

I wanted to say "shut the f**k up", but it's not very diplomatic

john_s - 22/9/02 at 10:09 PM

quote:
I wanted to say "shut the f**k up", but it's not very diplomatic

No, but it can be very effective!
John