General welding questions that dont fit in TIG, MIG, Stick, or Certification etc.
Round vs square tubing
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Farmwelding
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Why do they use round tubing in auto sports and monster truck type stuff. Does it have more impact resistance than square tubing? Square is a hell of a lot easier to fab to me so round tubing must have a better quality to it. Maybe the way it interacts with the wheels and upper frame? I don't know.
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Nick
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Poland308
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The round shape distributes stress in a more even manner. Due to this fact they can often engineer extra strength with less weight. I.E. smaller diameter tube with thinner walls.
I have more questions than answers

Josh
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Coldman
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Circles, cylinders and spheres are really interesting shapes and objects for many reasons.
Geometrically it can be shown they have the greatest surface areas and volumes per unit radius and surface area which means less material for same area or volume.
Engineering wise they have consistent distance from centrum to extremity (because its round) making load calculations easier from forces coming from any direction around the diameter compared to a square shape which has varying distance from centrum to extremity.

A tumbling roll cage can be impacted from any direction and multiple directions and each has to be allowed for in strength calculations, much easier to do with a round section. Also I suspect the round tube frame will be lighter than a square tube frame with the same strength.
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Coldman got it right
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Erich
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And round looks a heckuva lot better in a roll cage than square or rectangle.
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ex framie
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Also round tubing is stronger with less stress raisers due to no corners.
Its a better weight to strength ratio.
Can be a bugger to weld if you're not good at constant radius welding. Like me.

Cheers
Pete

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In addition to other comments, round tube can be bent any direction during the build process.
Dave J.

Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~

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What you talking about? Looks great!

Image

:)
Image
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Oscar wrote:What you talking about? Looks great!

Image

:)
image.png
image.png (91.55 KiB) Viewed 1923 times
Dave J.

Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~

Syncro 350
Invertec v250-s
Thermal Arc 161 and 300
MM210
Dialarc
Tried being normal once, didn't take....I think it was a Tuesday.
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Erich
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MinnesotaDave wrote:
Oscar wrote:What you talking about? Looks great!

Image

:)
image.png
Sorry square just does not cut it.
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GreinTime
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MinnesotaDave wrote:
Oscar wrote:What you talking about? Looks great!

Image

:)
image.png
I just died lol

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Antorcha
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You put that P.O.S. on my truck, you'll be removing it and I'll be moving on.
1.5" OD 15 ga is what I use for stuff like that.At least get a cheapo sq. die tubing roller and follow the roof line a lil. :lol:
Image
They work OK
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WildWestWelder
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Oscar wrote:What you talking about? Looks great!

Image

:)
Bends are stronger (when properly executed) than welds. It looks like someone had a bunch of square pieces laying around and decided to make a welding project. :)
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Bill w
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Must be planning on a side roll. The lights face left and right. Not out the front. Toyota guys... They all seem confused in the trails... Maybe it's better they use square tube. God will sort them out...
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Poland308
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You guys are looking at it wrong. It's a Texas truck. Those bars are gun rests and those are spot lights for hog hunting at night.
I have more questions than answers

Josh
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Poland308 wrote:You guys are looking at it wrong. It's a Texas truck. Those bars are gun rests and those are spot lights for hog hunting at night.
Bingo! Hawg huntin special!!!


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