I'm wondering why i shouldn't( figure i shouldn't cause i haven't seen it done before) bee able to weld a joint insted of bending the tube, the one i'm talking about is the bend in the cage, the part that goes from the stock roll cage to the dash, insted of to the windshield frame, could i not just cut and weld a joint to the desired angle and add a gusset?
or is there more structural strength in a bend?
just looking for an easy way out.
thanks:beer:

OK
First a bend will be stronger then a weld.
However I have done things like this in the past with no problems thus far. However the weld will make a huge difference i.e. If it is a crapy weld it wont hold squate

yeah, i do trust my welding, but if my life may depend on it i'll get it bent.
thanks.
:beer:

Tht would be my first choice..............Have it bent

if you do this, add a sleeve (smaller tube inserted tightly). I am willing to bet your life it'll be safe enough...:D

i have seen them used for nerfs. they have been abused and no problems.

If it's properly welded, it will be just as strong as the bent tube. The key is "properly welded" though. If you use a smaller OD tube as a sleeve, and plug weld the sleeve in place, it will be much stronger than the bent tube.

I can't believe none of you pansies have said this yet.

Get Bent !

cm ":flipoff2:" k

Hey Sharp, there's lots of stock car racing going on in your neck of the woods. Someone there must be bending tubing. A couple of bends shouldn't run you much coin. Muffler shops can sometimes make you some bends if they have the right sized mandrel and the equipment is heavy enough. I don't know if Terry Newhouse still races late models, but he and his dad ran Newhouse Engines in Brandon. Call them up and ask for Terry or his dad and they should be able to steer you toward someone that bends up cages. I'm not saying that you cant weld it strong as a bend, but if you want your work to be looked upon in a positive light and not look amateurish, have it bent. As well, as there needs to be a generous radius in a bend to maintain strength, I would make a front hoop and use straight spreaders to connect it to the main hoop, rather than bend the bars that run laterally. Your choice, guys do it one of three ways. Overhead hoop with radius, front hoop with radius, or the side bars with the bends. Stock cars tend to have the overhead bars all one piece with the hoop bent there, and straight bars running down to your feet.

Tim

What is the technique for cutting and welding rectangler tube? Like a matkins frame.

The problem with this is you would need to use heavier tubing or pipe to make it as strong as bent tubing.
The heat from welding tends to stress the area's that get welded
so thin tubing is out the window...
If you don't care about weight just use sch. 80 pipe and but weld fittings....this would be a bitch to make it look nice and you might get laughed at...but I would trust it's strength any day.
-Kerry

Originally posted by Tmartin
As well, as there needs to be a generous radius in a bend to maintain strength,

Tim

The "GENERAL" rule is, the radius should be no less than 2x the diameter of the tube.:)

Originally posted by BossGrip
The problem with this is you would need to use heavier tubing or pipe to make it as strong as bent tubing.
The heat from welding tends to stress the area's that get welded
so thin tubing is out the window...
If you don't care about weight just use sch. 80 pipe and but weld fittings....this would be a bitch to make it look nice and you might get laughed at...but I would trust it's strength any day.
-Kerry


remember PIPE IS FOR PLUMBING

Originally posted by 4x4extreme



remember PIPE IS FOR PLUMBING

sorry buddy, but you don't know what in the hell you're talking about. That is an old "wife's tale" perpetuated mostly by back yard "welders" on internet message boards.

YOU CAN BUILD A CAGE OUT OF PIPE. I'd love to hear some reasons why you can't.

Originally posted by 4x4extreme



remember PIPE IS FOR PLUMBING

Wow you must be brilliant:rolleyes: ...Pipe is for what ever the hell you do with it..:flipoff2:

It's true and I believe I said "if you don't care about weight"....sch 80 is very strong but heavy tubing welded at the corners would NOT be strong at all.

So if your going to WELD corners you should go HEAVY and sch80 pipe would be cheaper and plenty strong.....Not that I would ever do this myself....I still think you would be laughed at ....

I think I'll buy a bender and rent it to each of my friends to help cover the cost.
-Kerry

I think the danger is that the ignorant may just build something structural out of "pipe" without having any idea what that "pipe" is. Clearly there is pipe that is shit metal, not fit for anything other than carrying sewer and water or fence post,and then there is pipe that is engineered to withstand more stress than erw tubing of the same gauge. Generally speaking though, pipe means it was engineered to carry contents, and tubing for structural purposes. You got to know what you are working with. Some do, some don't. The guy that builds his roll cage out of stuff he finds lying around the yard... well, I wouldn't ride with him. Poorly designed and welded cages are dangerous in themselves, tube or pipe can act like speers impaling passengers. I used to tech race cars and some of jokers that brought out first time cars were unbelievable. Seat belts tack welded to cages, jerry can gas tanks, booger welded galvanized "pipe" cages, ....

Originally posted by Tmartin
I think the danger is that the ignorant may just build something structural out of "pipe" without having any idea what that "pipe" is. Clearly there is pipe that is shit metal, not fit for anything other than carrying sewer and water or fence post,and then there is pipe that is engineered to withstand more stress than erw tubing of the same gauge. Generally speaking though, pipe means it was engineered to carry contents, and tubing for structural purposes. You got to know what you are working with. Some do, some don't. The guy that builds his roll cage out of stuff he finds lying around the yard... well, I wouldn't ride with him. Poorly designed and welded cages are dangerous in themselves, tube or pipe can act like speers impaling passengers. I used to tech race cars and some of jokers that brought out first time cars were unbelievable. Seat belts tack welded to cages, jerry can gas tanks, booger welded galvanized "pipe" cages, ....

No not quite. Plain ole A53 ERW "water pipe" with a yield stress of 35,000psi will work just fine if the cage is properly designed (I agree, no galv. pipe) . I can't stress how important design is. You can't just throw a bunch of tubing together, no matter the grade of material, and expect it to be "strong". A good design makes MUCH, MUCH more difference than what material is used.

Here is a little comparison between relative "strengths" of lets say, a 60" long A53 1.5" scd 80 (actually 1.9" OD) pipe (35,000psi yield) & a 60" 1.75"x0.120" 1020 DOM tubing (70,000psi yield).

these are the allowable loads in compression:

1.75"x0.120" DOM= 7.7Kips or 7,700 pounds
1.5" scd80 pipe=13.5kips or 13,500 pounds

quite a difference huh?

In fact, in compressive loads, the yield stress of a material makes little difference in the "strength" after a certain length.

If weight is not a concern, pipe, even "water pipe", is just fine.

ahhhh screw it! just use PVC:rasta:

Originally posted by Cutter
ahhhh screw it! just use PVC:rasta:

:eek: Or copper and solder the M,Fer!!

so if i do get it bent will a gusset that doubles as a grab handle be advisable? since the weld may weaken the tube?

i just picked up the DOM today, and i was told to try a muffler shop, they may be able to bend it for me, so i'll check that out.

Originally posted by Sharp
so if i do get it bent will a gusset that doubles as a grab handle be advisable? since the weld may weaken the tube?

i just picked up the DOM today, and i was told to try a muffler shop, they may be able to bend it for me, so i'll check that out.

No a gusset doubling as a grab handle won't weaken the tube.
Will actually make your bend stronger.
I doubt a muffler shop can bend DOM, look into a bender

http://communities.msn.com/TheMINIHummer/rollcage.msnw

well went down to a muffler shop that lots of guys in the area suggested, and this is the result, i'm happy, it turned out better then i thought and didn't cost too much, i don't think strength will be an issue once i add the gussets to it, kinda like the one in the pics.


:beer:

Nice, did you just take it to a local shop, or a nation wide one?

Midas did it for me, i guess there are alot of stock car guys around here and they all suggested i go there.