Stock Roll Bar metal?

[Hedgehog]

I'm actually going against some of my earlier statements. I'm going to modify the existing roll bar on my '75 CJ5 . It will be very roll cage like, but not actually intended as true roll cage duty.

First off I'm going to cut off .... yes I said cutoff ... the angles down tubes going to the rear on the exist. bar. They will be replaced with a more or less 90* bar configured the very similar to the Wrangler's roll bar of today. Some may and will ask why? The stock bar is one of the type with a straight or 90* main roll bar with the angled down tubes starting inside the top radius creating a compound angle. I'm sure this is a very strong arrangement, but it makes it almost impossible to hang or attach anything to the roll bar. I will be using 1.5" Sch. 40 gas pipe. The configuration I'm going to use will allow easy and clean attachment points along with a flat top angle where a basket (like is found on pick-up camper shells) can and will be attached creating a two layer storage space accessible from the ground.

The second phase will be a front, behind the wind screen bar, very similar to a roll cage, but terminating or going under the dash to keep from hindering ingress and egress from the already cramped CJ5 doorway. the top of the bar will have 3 or 4 bars running back and welded to the exist. factory roll bar. They will incorporate a "hump" designed to keep the bikini top from smacking the top of the passengers heads. Two at the very outer edge of the passenger seat space and one possibly two in the middle to hang stuff from. I think I'll be using 1.25" or 1" Sch. 40 gas pipe.

The real question is, what kind of steel is the stock factory roll bar made of? Is it something special or plane old cold rolled steel "pipe"?

 

[Hedgehog]

So why am I doing this.....?

In quite a number of places the new pipe will be drilled and nut coupler nuts will be welded in place for convenient attachment points

There aren't any convenient place to attach items to the jeep. Like High Lift Jack, an ax, gun cases or any of a dozen other things that are nice to have on a back country Jeep.

The front portions of the "cage" will be used to attach the front part of the boat rack I've been working out in my head. Likewise, the back addition will be used for the rear portion of the boat rack.

 

[TexasBlues]

sounds like a plan... how bout some sketches?

im kicking round the idea of mounting a pre-runner style spare carrier in my bed... don't want a rear seat...

kinda like this

http://www.certifiablejeep.com/images/reartire/104_0441.jpg

 

[GARGOYLEJEEPER]

DOM under 3500lbs & 2" x .120" ERW over.

Check out Rockhard4x4 for ideas on the front dash parts and rear cage. I would do it the same as them, but be able to use the OE knobs for the WS instead of bolts.

Have fun, measure twice cut once.

 

[Hedgehog]

A couple days ago I was reminded that there is still goodness left in this world. After work I ran to the closest steel supply store. Entered the office and the counter girl looks at me and goes, "Darn it". What do you want? She wasn't really rude, but obviously in a hurry. I said that I needed some sch. 40 steel gas pipe. A manager came out of his office and told the girl to go on home and he'd take care of me. He brought me to the back and he asked if shorted pipe would do for what I needed and lead me to their remnants rack which had quite a few 4' pieced of what I needed. So I pulled out 2 and he insisted I get another, then when I started to pay he said, "Don't worry about it, pay it forward." The whole episode made me feel better about the world today.

Texasblues - A carrier like you want is sure a neat way to carry a spare tire, but it also commits ALL cargo space. Be careful to reinforce the bed though. Someone had something similar in the bed of my '75. What ever it was it tore a couple big ragged holes in the bed with quite a few stress cracks. The metal is fairly thin. I didn't have my MIG welder when I tried to weld the cracks and hole. The holes are closed, but I did make a mess of it. One day the old girl will get a nice new bed ..... maybe a wood bed like the old pickups had.

 

[Hedgehog]

It surprised me, but the "Hard Rock" page gave me a couple ideas. One being the handle. Gotta be careful about placing it so you don't bash your brains out bumping around in the rough stuff though. I like the center bar arrangement. Two bars with a center plate between. It also helped me solidify my plans for the dash attachment for the front windshield roll bar. I.E. solid 2" angle iron running up the dash on the side edge. With the addition of very heavy steel hidden behind the dash going to the floor. Yes, I can hear it now, "a good roll cage is attached to the frame." Remember, this isn't meant to be a true a roll cage, its a feature designed to add attachment points to the CJ5 .

 

[GARGOYLEJEEPER]

Score.

After the 20/20 CJ5 fiasco it is a sport bar, roll was a nasty word at AMC.

We want some pictures (of the counter girl ) when you have some good cage fab going on.

 

[Hedgehog]

I'm kind of excited. Last week I got a H-F bender and used the extra pipe to work out potential problems. Everybody likes to bad mouth the cheap H-F bender, but it worked out fairly well. Nice clean 90* bend, unfortunately the outside rollers made dents. This is easily over come by moving the rollers out and using extra steel shims under the rollers for extra support. I am impressed with the over all quality of the 1.5" gas pipe, a nice smooth finish with few if any blemishes. I did do due diligence in researching pipe v.s. tubing. Tubing seems to be great in a 200 mph crash where it's important to absorb some impact energy before it gets to the driver. Pipe holds up far better in slow motion jeep type roll overs where you are trying to save the jeep body and your skin. This will due nicely for my intended use.

Yeah I was trying to call it a roll bar not a roll cage, sport bar is probably a better term though.

I'm getting old enough where the counter girl looked like my daughter, so there would be no joy in seeing a picture of her from a camera I had control of.

 

[PaRenegade]

I can't say for sure 100% but I believe it was either hrew or crew tubing, iirc from what I've read. But if when you cut it open and you find no seam on the inside, then it's probably dom tube. I don't believe it's pipe.
I'm not sure of the o.d. on those older roll bars but the newer ones that go to the floor are 2 1/4" in diameter and tube is measured by the outside (inside varies) whereas pipe is measured by the inside (outside varies).
I'm sure you know this already but there is a difference in strength between black pipe (iron), steel pipe, and steel tube. Roll cages are made with steel tube for safety reasons (stronger).

 

[Hedgehog]

After MUCH reading I don't believe that Tube is actually stronger. Tube tends to bend where pipe doesn't or at least doesn't bend in the same way. Safety comes in where the tube will bend and absorb energy where pipe bends in a different way. Much has been written on the subject with both camps setting their heals in and not moving on the subject. Well that isn't exactly the truth. Some very sophisticated frame/roll cage manufacturers build out of both materials. Using tubing to save weight on the top or middle of the structure and gas pipe where the frame is likely to hit something solid like rock, rock sliders are a great example. Remember, tube is generally bent in a bender that uses hand/arm pressure only and pipe uses a 12 ton hydraulic press. When it comes to the metals used tube and pipe manufacturers say both use the same metal. I'm sure the real difference is in the wall thickness where tubing is thinner and pipe is thicker.

All in all for my purposes it doesn't matter, I'm not even pretending to use this as any sort of a roll cage. I want it to be strong enough to support my boat, high lift jack, ax and shovel. Beyond that, if it adds a little protection so-be-it, if not my life isn't really worth saving anyway.

 

[GARGOYLEJEEPER]

Hedgehog,
I was trying to be funny & make light of the situation, I am as old as you are.
Because of the bar from roll to sport we lost the CJ5 and got wide on the 7. And ended up with warning stickers. Thanks 20/20.

 

[Hedgehog]

Gargoylejeeper - I know it, sorry if my response sounded like I took some sort of offence, far from it my friend. We were just talkin', havin' a conversation. My skin is far thicker than that. It wasn't my intension to be negative at all. In my head the post was all about us passing around information we've gathered over the years. The finished product will definitely look very roll cage like, but I know that structurally there will be very little in the way of triangulation which is important for true roll cage like strength.

 

[GARGOYLEJEEPER]

Yeah it is all good, I just wanted you to know how old I was (since it is not on my info), and I took no offense what so ever & I have a young princess myself. The thing is I want to see you do this, because I will be doing the same thing next year, and will be looking forward to what you have done. And I/we want to see pictures.
There is a shop here in town (Bronco Bob`s) that just advertised on CL, wanting a CJ7 to make a cage for $200 so he can get a pattern and start production. At this time of year $ is kind of tight, yet I spent $ on a 400lb scale, so I can remove some of my museum pieces (Jeep Parts) as my Queen calls them.
For strength use cross bars or gussets, when I do mine I will have to do the rear major strong & safe. I was told make it safe for them, if I get the kids hurt she will kill me. My 2A already has full cage & 3A/B rear seat, the 7 does not have either, but will.

Thanks for understanding, and I am sorry for the confusion.

 

[Hedgehog]

Jumped out of bed this morning just itchin' to bend some steel, but got a call from a buddy. I'm working on one of his guitars and he wants it before the holidays. So, I guise I'm a Luthier for a little while today. ..... But I'd sure like to drop by Willys Works today, jeeps, they are an addiction.

 

[tarry99]

I'm always amazed when folks talk about Roll Bar or Cage construction , and further amazed when the topic of materials enter into the conversation.

To answer your first question the stock "Sport Bar" which is correctly named due to its lack of strength and protection and is made from HREW tubing that has a tensile strength of about 69,000 psi and a yield of 40,000 psi.

The AF53 Gas Pipe you propose to use for whatever purpose is only 48,000 tensile psi and a yield of 30,000 psi................so the HREW in it's simplest least desirable form of tubing is in fact stronger by over 25% versus ordinary threaded Steel Black Gas Pipe...........

DOM ( Drawn over Mandrel ) Tubing is about 82,000 tensile and 72,000 psi.
No reason to even bring Chrome Moly Tubing into this conversation.

Notwithstanding the Black steel pipe is a Pain to weld without first cleaning the rough scaled black exterior of the weld zone first , no matter what the use may be.

And I would like to see your backup on this statement.........

"Much has been written on the subject with both camps setting their heals in and not moving on the subject. Well that isn't exactly the truth. Some very sophisticated frame/roll cage manufacturers build out of both materials. Using tubing to save weight on the top or middle of the structure and gas pipe where the frame is likely to hit something solid like rock, rock sliders are a great example".

There is "NOT" a licensed Roll cage manufacture or SFI certified car builder in the country that uses Gas pipe in any form in there safety equipment or products period.

Point is , the difference between material cost is minimal as compared to the cost of labor to build and install so why not use a better material?

I'm not trying to give you a hard way to go........but there are allot of other folks that read these forums and keeping with the facts and good information should be everyone's responsibility.

 

[PaRenegade]

Not to jump on you either Hedge but I've never seen "discussions from the other camp that says pipe is just as strong" in my reading. And I agree that any sanctioning race group will not allow "pipe" of any type. Most want dom for the lighter vehicles and chrome moly for the heavier ones.
And on a side note. If your looking for pre-bent pieces for roll cages you might want to look at Extreme Custom Fabrications in a search. They offer both hrew and dom.

 

[Hedgehog]

Tarry99 - Your post is typical of those I've read and read again on other forums. No, I'm not talking about sanctioned racing roll cage manufacturers using a combination of both types of pipe and tubing for roll cages. The type of people I am referring to are those that play at their off road game and are serious about it. Over and over again I've seen examples of bent/dented tubing and under the same situations pipe that is still unbent and structurally sound. It is my opinion that sanctioning organizations that certify roll cages really don't give a darn about the vehicle, they are concerned with saving the drivers life. Tubing that bends burns energy in a crash, pipe that doesn't transfers that energy to other places including the soft squishy part that is the driver. I understand your point, I'd be stupid not to, but then again in this very thread I've stated over and over again that I am not building a roll cage, I'm building a system to attach items to. Honestly I don't give a darn about roll cages or the arguments that material used brings up. If my jeep flops at 3 or 4 miles an hour and I get crushed in the process, so-be -it. The gas pipe I'm using is strong enough for my application and that is good enough for me. By-the-way, the pipe I'm using is uncoated, smooth and beautifully clean steel. Since plumbers and gas technicians weld this pipe everyday I don't expect any problems welding it.

My original post about the type of steel the rollllll .... sorry ... the factory sport bar is made of was to find out if the steel would take a weld with normal welding practices.

PaRenegade - I agree, as stated above, the sanctioning organizations don't care about saving your vehicle, they are trying to save the drivers life. Generally those drivers are traveling considerably faster that most of us will while out on the trail lookin' for ghost towns, nice views or critters to hunt. Recently on one of those car fix-up shows on TV they said that a repop car hood was far stronger than a factory hood. Why? The factory hood was designed to bend in a crash. The repop hood would slide back and cut your head off in a crash. I believe this is almost exactly the same story, but used for roll cages. And I will repeat once more for those that worry about such things, I am not making a roll cage. Guys, I'm not trying to start an argument about roll cages or the material used, what I'm making is probably more closely related to a ladder rack on a pickup than it is to a roll cage.

 

[PaRenegade]

I hear what your saying and if safety is not the issue then pipe will suffice. I used pipe in mine for grab bars and overhead console support. Heck I remember as a kid knowing of guys who used muffler pipe to add to the stock sport bar. Not sure if it was young naivety (false security) or just for looks.
As long as those reading this down the road understand there is a difference, AND should you ever part with this Jeep I would think a disclosure should be made. Those are my concerns.

 

[Hedgehog]

What a great day! There will be pictures, but not right now. First thing 2, 2" od (1.5" ID) pieces to 90* for the back portion. No problem with the bending. Honestly with all the bad mouthing the Harbor Freight pipe bender gets I expected some trouble. The bends are smooth and problem free. A true bend snob might be able to find a VERY small amount of rippling, but you'd have to look hard to find them.

For the end chamfer a bi-metallic hole cutter was used. I've never successfully used one of these things but this time it worked to perfection. If I'm up to the welding, the joint will be very professional looking. Then comes the accessory attachment points. At this point I have no idea what or how things will be attached, but I have points to work with. The points themselves are 3/8" coupling nuts welded into the pipe structure.

Next will be cutting the old angle pipe off and welding on the new parts to the main part of the exist. "Sport Bar". How this will happen I really don't know. Either the pipe (one at a time) cut off, ground smooth and the new pipe spot welded in place or the thing will have to come off with all the work being done on the floor of the garage. Eventually the original "Sport Bar" will have to come off. Final welding will be simply to much heat to be done "in place". I'm lovin' this project.

PaRenegade - Thanks for the advice on a place to find pre-bent Tubing or Pipe. The whole point of doing this Jeep is for me to do as much of the work as is possible by myself. Sort of therapy. A time to prove to myself that I actually can do these things. It's a process, find a problem, think about it for a while, collect tools and overcome potential problems (this forum is good for that), then do the job as best I can. I love it this way.

Tarry99 - The Gas Pipe welded perfectly. Compared to some of the steel I've welded lately this stuff welds like a dream. It is clean, but mostly because it isn't welding 18 g. sheet metal. Man that gets old. It's nice to dial up some power and melt some real metal without blowing though and having to back up to fill holes. Welding thicker metal almost seems like cheating.

 

[mstar]

Hedgehog, did I read that right ? 2" odx 1.5" id = .250" wall thickness.That H/F bender must be stout.I haven't build any rollbar/sportbars in a while so just surprised at how heavy that pipe is. I am sure you will have no worries of collapsing it. mike