Black "poop" Pipe Cage

[THRASHER]

I am sure some of you saw this thread on pirate about the guy who flopped his runner after using black pipe to build his exo....

http://www.pirate4x4.com/forum/showthread.php?t=342992&page=1&pp=25&highlight=poop+pipe+cage

IIRC BrettM is also using this stuff on his MJ after he took the bed off...

I know it isnt as strong as dom, but I think that it would be better than nothing in a rollover....what do you guys think, anyone had any experiences with this stuff.....

to a college student, at 99 cents a foot and bendable with a $99 HF bender this looks like a good material to use for a cage....any opinions?

[AZTurtle03]

Surely pipe is not as strong as DOM. However, you are right that the price sure is pretty to a student! I know as this is what I did.

I used pipe in my TJ to add to the factory rear half of the cage. The way that I looked at it is that it may not be safer then tube, but it is certainly safer then what is there from the factory. I took it all the way down to the floor and plan to bring it to the frame next month.

I think if it is all you can afford, then definately go for it. It is definately stronger to use pipe then to have nothing at all. However, I would also suggest saving your pennies so one day you may get a tube cage.

Turtle

[goodburbon]

man those guys on pirate are #$%ks, just blasted the poor guy up and down for building a cage out of pipe.

I had never been there before.

IMHO, and I worked with pipe several years, i1 1/2 inch sch40 pipe would be fine for flops, and skidding, and protecting the body at large. if you get into an extreme rollover situation they all bend, and its better than nothing. it is heavy though.

[AZTurtle03]

On the weight issue... if you compare 1.25" Sch40 pipe (ID - 1.25" OD - 1.66") and HREW 1.75 .120 wall tube the pipe weighs 2.2lbs/ft where the tube weighs 2.1lbs/ft. Not enough of a difference to make a big issue I don't think.

Turtle

[Ludakris]

Huh, havent seen any red letter responses yet...


I'll sit back and wait.......

[Jes]

Huh, havent seen any red letter responses yet...


I'll sit back and wait.......


As has been shown in the past, people will do what they want despite the good advice they receive.

[1990XJ4x4]

Well i guess a Pipe cage would be better than nothing. If it is well designed and fabricated, it could hold up better than a poorly designed Chromo cage. I havent started building a cage for mine yet because I am still in the process of learning tube chassis design and anylisis. Even though I will be designing a small mini baja car made from Chromo tube, the process of anylisis and design will be similar. In short, design it well and you can come out with good results.

[BrettM]

Yes, I use some on my bed, not for a roll cage.

http://img48.echo.cx/img48/2482/img0688resize7fm.md.jpg

If you use good pipe, it has basically the same properties as HREW tube which many people have no qualms about using for cages. The 2 major complications that arise are (1) cheap chinese crap pipe. If you're finding pipe for a buck a foot, I can almost garauntee that it's crap. I was paying $3/ft for good pipe in the 1" schd 40 size (1.31" OD). And (2) bend quality. When you use a HF pipe bender it flattens or even kinks the bend. When you use a tube bender like a JD2 it keeps the cross-section of the tube circular through the bend.

I pipe cage can certainly be made that will withstand many rollovers (I've seen many of them) but it will be heavier than a DOM cage of similar strength. Either way your design is HIGHLY critical.

[Mr.OverKill]

i like the idea that any cage ( designed well ) weather out of DOM or Pipe is better than no cage at all. but in all seriousness, safety is first and if you cant afford a tube cage but you can a pipe one ( i know i might get some s#1t for this) dont go wheeling and save the extra gass money you would spend untill you get enough for the tube. THEN you can giter dun right

[BrettM]

good pipe costs just as much (or more) than HREW tube. it's the bender that is so much cheaper, and of course the worst part of a pipe cage. make friends with someone with a tube bender, find some people in your area making a large tube order, and it will be cheaper and better than pipe. that's what I'm doing.

[THRASHER]

good pipe costs just as much (or more) than HREW tube. it's the bender that is so much cheaper, and of course the worst part of a pipe cage. make friends with someone with a tube bender, find some people in your area making a large tube order, and it will be cheaper and better than pipe. that's what I'm doing.

I think I am going to do just that....in the process of moving up to chico and my roomate up there is tubing is runner right now so I will have access to a bender in a few weeks....

[badron]

There only one problem when using 40. You can't really come back and bitch because it not to be used for this kind of thing. Pound for pound is just fine. Been using it for over 30 years. As soon as someone rolls a poorly welded, badly fitted, improperly design cage and it comes apart they say "next time I will use a better pipe" BULLSXXT Most third party people don't use 40 so when someone try to sew them. They have there butts covered by using the "right pipe"
Use it, it's strong cheep, and right down the street at the hardware store.

[XJ_ranger]

id love to use pipe, then i wouldnt have to buy a bender and i could just screw the fittings together instead! i wouldnt even have to weld anything!

i had never thought of this -
thanks guys!

[Maximus]

I am in no way a fabricator but I have a little experience with both. Sch.40 pipe is great because it is cheap and you can even buy weld in 90's and so forth. Now I have only used some of this for racks and bumpers and sliders and stuff.

Companies such as Poison Spyder uses HREW in most of their buggy chassis so it can be strong enough if the design and execution is correct. Nowadays there are enough companies offering cages for you that would be designed probably better and are reasonably cost effective. Check T&J out of So. Cal if I remember have a full cage for about $1,000.

Good luck with whatever you decide.

[Ramsey]

and d and c extreme have one for 425. i'm gonna get it one day. of course this is advanced tech so a prefab cage doesnt quite belong

[5-90]

Could you build a cage out of plumbing pipe? Certainly. Would it be worth a damn? Iffy. Should you do it? No.

Pipe is not designed to serve as structural elements, it is designed to contain fluids or gasses at pressure. Pipe can be bent relatively easily (the only easier to bend metal tubing I can think of is EMT - which isn't even designed to hold pressure,) and any column strength it has is accidental.

Structural tubing can come in two flavours - REW (split into HREW and CREW) and DOM/Seamless.

"REW" means "Rolled and Electrically Welded" (H - Hot Rolled, C - Cold Rolled,) and this tubing will show a definite and pronounced "seam" where the edges were butted together and welded. While this can be used for light structural duty, it should be uses where static stresses will be encountered, and the tubing seams carefully placed to avoid rupture under load. If REW tubing fails, it's at the seam - nine times out of ten.

DOM - "Drawn Over Mandrel" is made from a solid, usually round, shape, that is heated and pulled over a shaped and pointed mandrel. The mandrel is sized to provide the ID of the tubing, and it is located within a drawing die. The amount of material used and the size difference between the mandrel and the drawing die determine the wall thickness and strength.

DOM tubing carries the advantage of being seamless, which simplifies fabrication by allowing you to orient the tubing in any direction (since you don't have to watch out for the seam.) DOM can therefore be loaded in nearly any direction that you would normally load tubing, and you don't have to worry about popping the seal - like you would with HREW/CREW.

DOM is also typically made from 4130 Chromium-Molybdenum alloy steel (or something similar - 4140 and other 41xx and 43xx alloys,) which is an alloy blended for weldability and minimal loss of strength in the Heat Affected Zone (HAZ.) Most ferrous alloys experience a severe loss of strength and embrittlement in the HAZ - which is how the various Cr-Mo alloys came to be.

It is still suggested that electrically welded Cr-Mo alloys are heat-treated after welding to reduce hydrogen embrittlement and loss of hardness/strength in the HAZ, but this can also be overcome by gas welding, rather than electrically welding. Gas welding should be done with a "carburising," or slightly acetylene-rich, flame, which works to prevent oxidising of the base metal, and works in much the same manner as welding flux.

I know I've gone into a lot of detail here, but it's important to remember 1*, and when it's yours on the line, you should do everything you can to tilt the odds in your favour. If you can't do it right, save your nickels until you can - it's cheaper in the long run, since you won't place confidence in something that doesn't deserve it.

I'm not trying to be an a$$ like the guys at PoR (I enjoy BillAVista's tech goodies, but I don't get into discussions much there...) but if I'm going to go into detail on something like this, I want you to understand why I'm saying what I'm saying. Blame it on middle and high school - the most common question on examinations was "Explain your answer" - which you were expected to do whether you were right or wrong. Frankly, I don't want to see anything happen to you that can be easily avoided...

5-90

(1* - One A$$ To Risk - especially when it's yours.)

[BrettM]

Could you build a cage out of plumbing pipe? Certainly. Would it be worth a damn? Iffy. Should you do it? No.

Pipe is not designed to serve as structural elements, it is designed to contain fluids or gasses at pressure. Pipe can be bent relatively easily (the only easier to bend metal tubing I can think of is EMT - which isn't even designed to hold pressure,) and any column strength it has is accidental.

Structural tubing can come in two flavours - REW (split into HREW and CREW) and DOM/Seamless.

"REW" means "Rolled and Electrically Welded" (H - Hot Rolled, C - Cold Rolled,) and this tubing will show a definite and pronounced "seam" where the edges were butted together and welded. While this can be used for light structural duty, it should be uses where static stresses will be encountered, and the tubing seams carefully placed to avoid rupture under load. If REW tubing fails, it's at the seam - nine times out of ten.

DOM - "Drawn Over Mandrel" is made from a solid, usually round, shape, that is heated and pulled over a shaped and pointed mandrel. The mandrel is sized to provide the ID of the tubing, and it is located within a drawing die. The amount of material used and the size difference between the mandrel and the drawing die determine the wall thickness and strength.

DOM tubing carries the advantage of being seamless, which simplifies fabrication by allowing you to orient the tubing in any direction (since you don't have to watch out for the seam.) DOM can therefore be loaded in nearly any direction that you would normally load tubing, and you don't have to worry about popping the seal - like you would with HREW/CREW.

DOM is also typically made from 4130 Chromium-Molybdenum alloy steel (or something similar - 4140 and other 41xx and 43xx alloys,) which is an alloy blended for weldability and minimal loss of strength in the Heat Affected Zone (HAZ.) Most ferrous alloys experience a severe loss of strength and embrittlement in the HAZ - which is how the various Cr-Mo alloys came to be.

It is still suggested that electrically welded Cr-Mo alloys are heat-treated after welding to reduce hydrogen embrittlement and loss of hardness/strength in the HAZ, but this can also be overcome by gas welding, rather than electrically welding. Gas welding should be done with a "carburising," or slightly acetylene-rich, flame, which works to prevent oxidising of the base metal, and works in much the same manner as welding flux.

I know I've gone into a lot of detail here, but it's important to remember 1*, and when it's yours on the line, you should do everything you can to tilt the odds in your favour. If you can't do it right, save your nickels until you can - it's cheaper in the long run, since you won't place confidence in something that doesn't deserve it.

I'm not trying to be an a$$ like the guys at PoR (I enjoy BillAVista's tech goodies, but I don't get into discussions much there...) but if I'm going to go into detail on something like this, I want you to understand why I'm saying what I'm saying. Blame it on middle and high school - the most common question on examinations was "Explain your answer" - which you were expected to do whether you were right or wrong. Frankly, I don't want to see anything happen to you that can be easily avoided...

5-90

(1* - One A$$ To Risk - especially when it's yours.)
That's some good info there 5-90, a few issues I have with it though;

first, pipe is used in some scenarios for structural members, not just containing gas and liquid. there were several engineers on POR that showed large structures they've had a part in building which used "pipe" for structural purposes. I think your analysis is a good rule of thumb, because you must get the right grade of pipe for structural purposes.

second, DOM is rarely seamless. it is formed just like REW tube then drawn over a mandrel to provide for consistent ID and normalize the grain structure.

[5-90]

The process of "drawing" is pulling a (formerly) solid form over a mandrel of some sort to get a hollow shape - and it is done on materials that are too hard/stiff to work with extrusion (aluminum can be extruded, since it is relatively soft. Steel is drawn - which actually results in less stress on the die and mandrel.)

If the "drawing" process is done with a proper die and mandrel, you will end up with a seamless shape - the "fingers" retaining the mandrel are placed several inches back to allow the material to close within the die after passing. There is still a seam, of sorts, but it's not a welded seam - which means there is no change in hardness/strength, and there is no stress riser due to the HAZ. Therefore, DOM can be considered "seamless" for all but the most critical applications.

If it's rolled/welded, it's rolled/welded. If the tube is drawn over a mandrel then welded, it's still welded tubing. It is possible to force a mandrel through a welded tube to gain a clean ID, but you will still have the HAZ and the attendant stress risers - unless the entire section is then re-heat-treated.

I'd not heard of pipe used as a structural member, but I don't work with a lot of pipe (I REALLY hate plumbing!) I don't doubt that it's possible, but it's not something I'd advocate generally - and it would take more engineering know-how than I have at the moment to design a reliable structure out of Sch.40 or Sch.80 - so I'm not going to recommend it, since I can't offer useful advice (and I'm not there to inspect anyhow.)

Another factor that works against pipe is that pipe threads - internal and external - are nearly always cut into the metal, rather than rolled. This created enourmous interruptions in the flow of stress all around the threads, and makes for serious weakness at the joins - conventional fastener threads are rolled after heat treat, which essentially makes it a "forging" process - yielding a stronger thread. The fact that material is not removed during rolling is a plus - the roots of the threads become harder than the crests due to the compaction of the material, and that helps to compensate for the reduced strength at the thread root (a combination of deformation, reduced diameter, and the semi-sharp "line" at the thread root all contribute to this weakness.)

If you can find someone with a proven record of designing high-stress structures from plumbing pipe, go ahead. Otherwise, I think you're better off taking it easy and waiting to do it right...

5-90

[Highlander]

Just my .02

I work with black pipe all day long and by no means would I ever use it to protect myself or my investment. Most of the sch40 in my area is now shipped in from other countrys and isn't worth the money we pay for it.
When you can take 1" sch 40 and bend it over your knee it should tell ya something.....

[Roll-over]

... So the concensus is that "pipe" is fine for bumpers, sliders, and fender hoops. But NEVER use it for the exo cage that in many designs attaches to the bumper, sliders, and fender hoops? So here's an ironic question... When did HF start selling logic and what kind of return policy did you get?

[XJoachim]

Sorry, a cage should attach to the frame or some sort of frame. Then it may extend to bumper, fender and sliders. The main thing is to secure the passenger area, if you tie it in your bumper like an exo that is to protect a bit of sheet metal. This is usually just an extension of the cage and not that critical.

[5-90]

Don't worry - I wouldn't use pipe for bumpers and such, either - not on a vehicle.

Any safety device deserves the best material you can get! In pretty much every case, that means material that was designed to take sudden loading when used structurally.

The ideal design for a cage would be one where the body could literally disintegrate around the cage, but the cage and its occupants would still be intact. The seats, ideally, would mount to the cage - as well as driver restraints - and the rest of the vehicle would be designed around it.

In our case, a number of compromises must necessarily be made - including using the lower part of the unibody to tie the lower part of the cage together (a good cage would have a "halo" bar, which could be screwed/welded to the upper unibody surround.)

Where you are forced to compromise in structure, you make up for it with material. End of story.

Call me cranky, but I've become attached to all my parts, and I'd like to keep them where they are (even the replacement parts...) Weight is not seriously an issue for us, so we should use the best we can get our hands on.

Besides, in strength/weight ratios, you'll do better with Cr-Mo steel than you will with pretty much any metal pipe. Save your money, and do it right later. Take it easy in the meantime.

5-90

[BrettM]

Just my .02

I work with black pipe all day long and by no means would I ever use it to protect myself or my investment. Most of the sch40 in my area is now shipped in from other countrys and isn't worth the money we pay for it.
When you can take 1" sch 40 and bend it over your knee it should tell ya something.....
now that is some ghetto-ass chinese pipe :shocked:

I used 1" sched. 40 for my "tube bed" and it's dragged on a number of rocks with no denting or bending, just some scuffing. of course I'm using good pipe...

[AZTurtle03]

MY XJ ADDICTION... I would be willing to bet that you couldn't bend 1.25" SCH40 pipe over your knee. Unless you are like Lee Priest or someone of that sort!

On the subject of pipe... Surely it is not as strong as tube... and it may fail... However... If your decision is PIPE or NOTHING, then I say run with the pipe!

Turtle

[xuv-this]

my .02- decent size pipe could potentally work well for a cage. if the cage is designed and assembled correctly (good fat welds with the right rods by someone who knows what they're doing) it would be fine. you could build a cage from angle iron if you designed the triangles into it right. the key is to make the cage so it will pull on itself. the problem is that you need to know what you're doing to do this. and if you do know what you're doing, you're probably going to realize that the extra pipe used would offset the weight/cost, and would want to do this the more expensive way.

[boynamedsue]

dont use pipe. i mean come on this your safety were discussing here do you realy want to risk injury just to save some $$$. if you want a good cage check out www.dandcextreme.com he uses 1.5''.120 wall hrew, and it fits awesome, strong as hell too. it sells for about $450 plus shipping . i've never seen someone break his products.

[Roxtar]

I wouldn't use it on anything.
Why would you go through all the labor of making a cage, bumper, or whatever, and use poor quality materials. I'm not saying you need to use DOM but at least go with HREW.
As much work as fabbing a cage is, don't you want to never have to do it again?
Don't you want to KNOW it'll work?
Even more so with smaller jobs like bumpers or sliders where the material cost difference is far more insignificant.

[TrailHunter]

The process of "drawing" is pulling a (formerly) solid form over a mandrel of some sort to get a hollow shape - and it is done on materials that are too hard/stiff to work with extrusion (aluminum can be extruded, since it is relatively soft. Steel is drawn - which actually results in less stress on the die and mandrel.)

If the "drawing" process is done with a proper die and mandrel, you will end up with a seamless shape - the "fingers" retaining the mandrel are placed several inches back to allow the material to close within the die after passing. There is still a seam, of sorts, but it's not a welded seam - which means there is no change in hardness/strength, and there is no stress riser due to the HAZ. Therefore, DOM can be considered "seamless" for all but the most critical applications.

If it's rolled/welded, it's rolled/welded. If the tube is drawn over a mandrel then welded, it's still welded tubing. It is possible to force a mandrel through a welded tube to gain a clean ID, but you will still have the HAZ and the attendant stress risers - unless the entire section is then re-heat-treated.



I hate to belabor a point, but BrettM is right about DOM. Mild DOM usually DOES have a seam. It is a welded tube that is then run through a mandrel which creates wall thickness uniformity and it's formed cold which adds strength. What you're describing is a process called extrution. That's how true seamless tubing is made.

In case you think I'm wrong, here's what Google's definition of DOM tubing is, http://www.google.com/search?hl=en&hs=p6k&lr=&c2coff=1&oi=defmore&q=define:DOM+tubing

Back on topic. I have never built anything using pipe, nor do I know anyone that has so I can't speak on the subject.

[RWKHausSupply]

FYI 4130 chromo can be had in so cali for only 4.55 per foot in a 1.75 x .120 wall! AND DOM 1020 for only 3.10 per foot both price includes Delivery! hell in 1.5 x .120 is under 3$ per foot!

Pony up the extra posket change and find a friend with a bender if you must! Daym what is like 40$ extra for tubing!?

[racer32]

Just out of curiosity, How many people here have built something out of pipe and had it fail?

[Roxtar]

FYI 4130 chromo can be had in so cali for only 4.55 per foot in a 1.75 x .120 wall! AND DOM 1020 for only 3.10 per foot both price includes Delivery! hell in 1.5 x .120 is under 3$ per foot!

Pony up the extra posket change and find a friend with a bender if you must! Daym what is like 40$ extra for tubing!?My point exactly.
Yes, you can make something out of cheap material and you may even get away with it but why would you want to?
As much work as these projects are, why would you use a sub par material that may or may not fail when it doesn't cost that much more to do it right?
I would hope that the pride of doing the job right would be worth it alone.
A serious case of penny smart and dollar foolish.

[RWKHausSupply]

Just out of curiosity, How many people here have built something out of pipe and had it fail?


ok thats a trick q.. a few reasons..

Those of us that are going to actually use the cage and do, know better then to skimp the very little additional $ for a true DOM or 4130 cage.

And those that do build a cage out of the laughable sch 40 pipe I doubt would show the related damage that occures after such a roll if it happens.

Given here at the mechanical design install and engineering firm I am employed at, we do use sch 40 not only for large pipe needs for water, chilled water, cond. water, and hot water, but yes even for pipe stands to support the product conveying pipe. So as it may be used for "stuctual" use its not for high stress applications.

Ever read any or all the rule books you can/could regarding cages or approved materials for cage work???

[TrailHunter]

I think everyone knows that you don't need to jump off a skyscrapper to know it's bad, but what he's trying to ask how many people have seen a pipe cage fail. I think it's a pretty good question, but it's not very usefull consider that most cages are built with tube and they have failed.

Are there any engineers that can tell us the physical differences between pipe and tube assuming similar wall thicknesses? Are they different allows, are there different grades within the same allows. Is the MFG process different? Or is like BrettM suggested and that quality pipe is the same price as ERW?

[RWKHausSupply]

Well I can say that Company price for sch 40 black PIPE is currently $1.68 per ft and weights in at 2.72lbs per/ft for 1-1/2 that has a 1.9" OD and 1.6ID @.145 wall thickness that is in a type E with 36(ksi) min yield stress rating and a 60(ksi) min tensile.

Same in a 1020 DOM is at 3$ per ft in 1.5x.120 wall and is 45-85 (most being at 65-70) yield strength, and 60-95 tensile with most being at 90. Wieght is at 1.76lbs per/ft.

so its lighter and a average cage would be in the range of 80-100ft and be a whopping 117$ more and wieght 86lbs less. Thats the obvious points. Now for the elastistic properties and the hardness differences, I am not currently able to quote those with out some guessing so I wont.

[xuv-this]

[QUOTE=ROBERTK]sch 40 black PIPE is 2.72lbs per/ft for 1-1/2 that has a 1.9x.145

Same in a 1020 DOM is at 3$ per ft in 1.5x.120... Wieght is at 1.76lbs per/ft.

so its lighter and a average cage would be in the range of 80-100ft and be a whopping 117$ more and wieght 86lbs less. QUOTE]
just to clarify on the weight, you are comparing 1.5 to 2" dia. tube
i don't know of anybody that runs a cage out of 1.5" tubing. mabye you can do the math on the weight per volume of metal used(i'm too lazy right now) i'm pretty sure that DOM is denser. the main physical difference between the two kinds is that poop pipe isn't as dense because it isn't nearly as pure, in addition to being a different alloy and different manufacturing processes. that's where the price and strength difference comes in.

[racer32]

...1-1/2 that has a 1.9" OD and 1.6ID @.145 wall......you are comparing 1.5 to 2" dia. tube...

Nope...

Pipe = I.D
Tube = O.D.
-----------------------------------------------------------------------
these are all stolen from Pirate...

rolled pretty hard from about 6 feet high onto granite last weekend. only piece of DOM on the cage is the only piece of metal(besides sheetmetal) that was damaged, all the POOP pipe is intact no cracked HAZ on welds....
http://www.pirate4x4.com/forum/attachment.php?attachmentid=194491&stc=1&d=1119909365
http://www.pirate4x4.com/forum/attachment.php?attachmentid=194492&stc=1&d=1119909469

Pipe exo-cage on probably a 4,500-4,800 lb truck. 25mph down a hill. Rearend started stepping out, then the truck went kind of end over end sideways for two full rotations. Very hard impact. No broken welds, just minor bending. He and his wife walked away. He had also rolled his previous truck with a pipe cage a couple of times without a problem.
http://www.supermotors.org/getfile/201163/fullsize/IMGP0654.JPG
http://www.supermotors.org/getfile/201160/fullsize/IMGP0652.JPG

[BrettM]

I am going to be making my cage soon, and it will be a combination of 1.25 Schd 40 PIPE (1.66 OD) and 1.5 .120 wall tube. I am going to use the pipe on the areas that will be dragging on rocks because of the thicker wall and more resistance to denting. The only reason I'm even going to use tube is for the weight savings on areas that won't be contacting rock frequently.

I spent about an hour BSing about pipe, HREW and DOM with the guy running my local steel shop (Valley Steel if anyone cares). He made several calls to his suppliers and even the actual steel manufacturers, and he found that the HREW and DOM are rated within 2% in strength, and the HREW and pipe are made using the exact same steel and processes, just different dimensions and not officially rated.

The only pipe cages you will see fail are the ones very poorly designed or with very poor bends from using a crappy bender. Same steel, same process, quit bitchen already.

[BrettM]

I hate to belabor a point, but BrettM is right about DOM. Mild DOM usually DOES have a seam. It is a welded tube that is then run through a mandrel which creates wall thickness uniformity and it's formed cold which adds strength. What you're describing is a process called extrution. That's how true seamless tubing is made.

In case you think I'm wrong, here's what Google's definition of DOM tubing is, http://www.google.com/search?hl=en&hs=p6k&lr=&c2coff=1&oi=defmore&q=define:DOM+tubing

Back on topic. I have never built anything using pipe, nor do I know anyone that has so I can't speak on the subject.
correct, 5-90 is describing Cold Drawn Seamless, not Drawn Over Mandrel, from Chicago Tube (http://www.chicagotube.com/stockbook/round/tech_t5_mandrel.html)

DRAWN OVER MANDREL has very little wall variation and no spiraling eccentricity. The tube is formed and electric resistance welded from flat steel which has very little gauge variation. Any wall variation that may exist in the flat steel runs in the same plane throughout the length of the tube, leaving the bore straight and true.



COLD DRAWN SEAMLESS has an inherent characteristic of eccentricity. In the piercing process a solid billet is heated and forced in a rotary motion over a piercing point to form the seamless tube hollow for subsequent cold drawing. It is impossible to keep the piercing point always in the exact center of the tube round during the piercing operation. As a result, wall variation is induced into the tube. Moreover, since the shell is turning as it is being formed, spiraling eccentricity is created. Additional hot and cold finishing operations greatly refine the dimensional accuracy of the seamless tube, but the eccentricity is never fully eliminated.

[racer32]

I spent about an hour BSing about pipe, HREW and DOM with the guy running my local steel shop (Valley Steel if anyone cares). He made several calls to his suppliers and even the actual steel manufacturers, and he found that the HREW and DOM are rated within 2% in strength, and the HREW and pipe are made using the exact same steel and processes, just different dimensions and not officially rated.

The only pipe cages you will see fail are the ones very poorly designed or with very poor bends from using a crappy bender. Same steel, same process, quit bitchen already.

Well put Brett. I have run pipe cages in 3 different hobby class racecars and have taken some serious hits and never had a failure... :)

[racer32]

and just for the record, I dont care what you build your cage out of; But if you build it like this you need to sell your tools and buy a Geo Metro... :eek: :rolleyes:

http://www.granitepath.com/photos/051001FunCrawl/DCP_7632.jpg

[Highlander]

MY XJ ADDICTION... I would be willing to bet that you couldn't bend 1.25" SCH40 pipe over your knee. Unless you are like Lee Priest or someone of that sort.

Turtle


Haven't tried it... I'll try tomorrow and send ya the hospital bill *LMAO*

[Highlander]

now that is some ghetto-ass chinese pipe :shocked:

I used 1" sched. 40 for my "tube bed" and it's dragged on a number of rocks with no denting or bending, just some scuffing. of course I'm using good pipe...
When I plumb in a sprinkler system and put the water in it you can watch it flex in the hangers...*L* Oh well cheaper pipe=more profit for the company...

[TrailHunter]

Then if it's essential the same with different dimensions and no certification for strenght, why are the benders different? I know on a serial draw like a 105/JD2, they have different dies for pipe, but I'm assuming it's because they specify it from the ID and it doesn't match tube exactly. So that begs the question about the cheapo HF style benders. I would guess that you'd get equally crappy bends from similarly sized tube and pipe.

[BrettM]

Then if it's essential the same with different dimensions and no certification for strenght, why are the benders different? I know on a serial draw like a 105/JD2, they have different dies for pipe, but I'm assuming it's because they specify it from the ID and it doesn't match tube exactly. So that begs the question about the cheapo HF style benders. I would guess that you'd get equally crappy bends from similarly sized tube and pipe.
as you said, you can get pipe dies for the good benders. you can also get decent bends out of a HF bender, but it takes a bit more work; you may need to pack the pipe with sand or gravel before bending, you may not be able to get as much angle on the bend as you like, the thinner the pipe the more the HF type crushes it so you may have to use heavier pipe than you like... etc

[VegasAnthony]

IMO
somethin is better than nothin
BUT
if you have ever used a mechanical bender you would understand what kind of work it takes to bend a cage , let alone notching and welding. It just makes sense to use the best quality material yoiu can afford..

I myself plan on using DOM on the portion of cage that surrounds the area of the passangers in the vehicle and HREW for the rest of the cage..

[8Mud]

It's been my experience in building construction use of piping, that the bends are the weak point. Second is the area next to the welds, which has rings of different grain structure and hardness.
Design pays a large part of the process. Some crush makes sense. A totally rigid construction, would likely want to separate at the anchors.
I wonder why nobody has experimented with a fiber foam filling for the pipes and tubing after construction. Which would be lightweight, add to rigidity and likely help prevent kinking.
Gussets (even ribs) and fill, would probably double the unit strength, with little weight penalty.
My brother ran into a boulder at 80 MPH, with his buggy, the frame and cage was made of black steam pipe, the construction used a lot of triangulation and had few bends. The front axle ended up under the drivers seat, cage intergity held.
Bends look pretty, triangles are stronger.

[CanMan]

I was thinking of using PVC pipe, you know, just for show..... Yea rite.

Not a bad idea on a budget tho. Ill stick with chromoly steel for mine tho.

[xjbubba]

FYI 4130 chromo can be had in so cali for only 4.55 per foot in a 1.75 x .120 wall! AND DOM 1020 for only 3.10 per foot both price includes Delivery! hell in 1.5 x .120 is under 3$ per foot!

Pony up the extra posket change and find a friend with a bender if you must! Daym what is like 40$ extra for tubing!?

Where, in southern Cal, can you buy the above mentioned chromo and DOM for the prices quoted? Delivered? I want some.

[8Mud]

I get my tubing, pipe, flat steel and whatever at two places cheap. I go to a wholesaler, that also sells, cut to length pieces and pick through there left overs. I pay by the pound, irregardless of the shape of the steel.
And I have a buddy, that loads rail cars with scrap steel. He sells me likely pieces for the cost of the scrap, plus a small handling fee. About 10% of the scrap, is serviceable and useful stuff.
The prices are typically 1/4 to 1/2 of the book cost. If you do medium to small projects, it really pays off in the long run.

[xuv-this]

i concurr with the scrap thing. it's perfectly fine to use scrap in a cage, if you use common sense. (no main hoops from used heater pipe, etc) braces and special brackets can be made a lot easier and cheaper. scrap where i live used to cost less than 20 cents a pound. problem is though, the way the price of steel has been going up, now it's above 30. but it's still a lot cheaper than new.

[RWKHausSupply]

Where, in southern Cal, can you buy the above mentioned chromo and DOM for the prices quoted? Delivered? I want some.

Look up EMJ in lynwood CA. or Tubular Steel Inc (909) 429-6900. just bought 290ft at 3.30per ft for 1.75X.120 DOM delivered

[Maximus]

Just for the record when Poison Sider Customs were Avalanche Engineering the "Assasin" buggy was moade out HREW. I don't remember the tube diameter or wall thickness but it was in a 4 wheel mag that was comparing the different buggies offered at the time.

In any case if the design is correct you can use something other than DOM or Chro-mo. I have used the SCH40 pipe in bumpers and so forth and even bent it with a HF bender, a couple rearendings later and it was just fine.

I think the key is more quality design.

[lankchevy]

ive rolled my xj with a poop pipe cage, it was a pretty soft roll, but the cage didnt move and im still alive.

[BrettM]

ive rolled my xj with a poop pipe cage, it was a pretty soft roll, but the cage didnt move and im still alive.
impossible!

[Ludakris]

impossible!


I think if you fill it full of concrete it really adds strength.. I have seen mailbox posts and basket ball hoop poles like this.. very strong...

[xuv-this]

I think if you fill it full of concrete it really adds strength.. I have seen mailbox posts and basket ball hoop poles like this.. very strong... :D :D :D is there ANYTHING that you can't use to build an xj? serously, though, that would make that cage like over twice as heavy.

[RWKHausSupply]

:D :D :D is there ANYTHING that you can't use to build an xj? serously, though, that would make that cage like over twice as heavy.


Well what about sch 80 (sch40HD) and filling it with helium!!!? :-) That would offset the weight right?

[BrettM]

Well what about sch 80 (sch40HD) and filling it with helium!!!? :-) That would offset the weight right?
better yet, hydrogen!

http://www.corrosion-doctors.org/Hydrogen/images/hindenburg-1937.jpg

[RWKHausSupply]

better yet, hydrogen!

http://www.corrosion-doctors.org/Hydrogen/images/hindenburg-1937.jpg


What are you stup-id or someding? It would be to lite and not get any traction then! Duh..:lecture:

[xuv-this]

:D:D

[woody]

Foam filled tubing???? :D

How do you fill the tubes w/o being invasive or leaving a gap at the nodes?

How does welding upon said foam-filled tubes for repair or adding things later work out?