yet another tube question: size matters?

[unabonked]

Someone in my last thread noted that 3" tubing with 1/8" wall would be very weak. As i have no experience in this (just saw simaler sizes used in some after market parts), i could use a bit of advice here.

The same person said 2" or smaller would be best. What about wall thickness? The welder i'm looking at can do up to 3/16" thick. Its the only one I can afford (under $500).

The bumper will be atached to the frame using two 3/16" "C" angles, wich will be reinforced to provide a mounting point for a winch, tow hooks, and pre-runner. The angles will bolt onto the frame rails using two 3/4" class 5 bolts.

 

[jimbo74]

2" would probably be stronger because there would be less leverage on a given part of attachment ie the weld....

 

[Broccoli1]

What welder are you looking at getting? I'm guessing it's a 110v and can do 3/16" with Fluxcore wire. Is that right? If so that's pushing the welder and the integrity of the welds.Especially if you are going to be making a winch mount bumper.
Regarding after market add-ons: if what you were looking at was 3" then it probably is considered a "show" piece ie. lightbars that mount in the back of pick-ups that look like rollbars, safari bars that mount on the bumper. Check out products that actually mount to the frame and come from a real 4x shop. PepBoys and such don't really carry anything trail ready.
If you are starting to weld check out this site:
http://www.hobartwelders.com/mboard/index.php?

 

[RangerX]

unabonked, the standard tube size, at least in this part of the country, is 1.5" with .120 wall. To a lesser extent, 1.75" .120 is used. I have both on my truck.
I'm no expert, but there are plenty of them here in SoCal, and I figure they know what works best.

 

[unabonked]

Yeah, i forget the make of the welder, but thats basically the specs capabilities. I origonally thought that 3" tubing would be best, but i have been told otherwise. I will probably go with 1.25-1.5" tubing with a .125 wall.

What difficulties will I be experiencing with using the this welder? will the joints be too narrow?

 

[prerunnersvo]

I'm using 1.750"x.120" tube on just about everything on my truck.

 

[unclemeat]

3" tubing is stronger than 2" tubing, because of the moment of inertia. I did not look it up but a 3" 1/8" tube would be as strong or stronger than 2" 1/16" tube. Yes I am an engineer.