square steel tubing

[beerbattered]

In terms of lateral strength in 1 1/4" x 1 1/4" square steel tubing, is a 90 degree bend roughly equal to a 90 degree weld? Would it depend on if the tubing was hot or cold rolled? I'm not sure on the radius of the die that the shop has but what would be ideal?

 

[Venice Motor Bikes]

I was told that a properly done weld is stronger that the parts you are welding because the metal used in welding is a higher quality than the metal in the parts you are welding together!

I would think that a proper 90 degree weld would be stronger than a bend because bending stresses the metal.

 

[2door]

To add to what Venice has said; bending square tubing will require a very long radius. 1 1/4 X 1 1/4 square steel tubing can be bent but to get a 90 degree bend would require a very long radius bend that wouldn't lend itself to bicycle use (if that is your goal) A tight bend would, as Norm says, stress the metal, crimping and stretching it at the point of the bend and seriously impact the strength of the assembly. Cut the steel at a 45 degree angle and weld it. (Don't use JB weld)
Tom

 

[Blakenstein]

There just better not be any squares comin around here to steel my tubing.

 

[fasteddy]

Mike, when I was young I rode with a bike club and I can only imagine what you saw that night. To have a guy like that creeping up on you would be your worst nightmare.

In the end though it turned out like I would imagine it would. Always found out they were usually ready to help a guy in need but I also learned never to cross them up.
Pounding your brains out your ears with that billy club would have been all part of a days work for him.

Steve.

 

[Blakenstein]

He turned out to be reasonable to you.....that's because ur not square!!

 

[beerbattered]

I'm building a single wheel trailer.
http://i119.photobucket.com/download-albums/o125/beerbattered/biketrailer-2.jpg
This trailer is going to have a bed on it that will add stiffness and all of the other components are overkill. It seems the weak link would be the bends. Is there a specific minimum radius? What radius would be ideal for 11ga. (1/8" wall thickness) 1 1/4" x 1 1/4" square tubing to be bent at 90 degrees and still retain most of its strength? Is there a "trick" to it?

 

[K.i.p]

I am in the "weld it" camp as well. If strength issues still concern you a couple gussets could be added at the 90.

 

[Elmo]

The above is good advice. It is almost always advisable to cut and weld rather than bend square tubing. Notice that I said almost. If you still want to bend it cheCK this out. Gingery's Pipe Bending Machine
ELMO

 

[Blakenstein]

I bought this frieght wheeler and made a 3 point hitch for it- I also drilled through the axle and installed machine bushings and 1/8 " cotter pins to lock the wheels on. Here are pictures of it.
Just finnished using it to pull a new hot water tank up the front steps-now Ill use it to take the old one out.Ill remove the hitch this time - it's in the way.




Haaa ha ha ha ha ha ha I just used my bike trailer to pull an old hot water tank up the basement steps and bounce it down the front steps -wheel it around to the back of the garage

 

[exavid]

Bending the square tube would take about three to four times the radius you can bend round tube of the same diameter and thickness. They are much more difficult to bend without buckling. The easiest way to handle it is to slot the square tube with a hack saw with a bunch of hacksaw kerfs in a row, bend the tube and then weld up the slots. If done carefully this can work well and look good. To keep the bend looking reasonably smooth and not like a series of flats the kerf slots have to be pretty close together, around 1/8" apart. An air driven die grinder will do the job or a regular hacksaw. But an electric angle grinder would make too wide a kerf slot to look good, the slots should be in the range of 1/16" or so spaced about 1/8" apart.

 

[Blakenstein]

Kerfs????? u know what a blade Kerf is?? Thats pretty cool -been along time since I heard that word-used to work in a plant that made pipe callers for the oil rigs. I ran 3 super huge automatic band saws and an old cutt-off lathe souped up with an Allen Bradley computer programed electrical atomated system to cut double extra heavy seamless machineable tubbing into blanks for the threading lathes. Yep-lots of fun.