Jeep Enthusiast Forums banner
121 - 140 of 1133 Posts

·
Registered
Joined
·
1,241 Posts
quiksand said:
I have a question. With all this talk about triangulation and hoops collapsing when unsupported, wouldn't that make the CJ and '87-'91 YJ cage superior to the later '92 and up Wranglers? I have this argument on the YJ forum all the time. But it seems to me that the early design is a lot stronger. There is really nothing keeping the '92 and up roll bars from just folding over in a rollover, it would seem to me. Any opinions?
Yup, you are exactly right.

The late YJ cage is much better then the TJ cage though. From straight above, the TJ cage looks like an almost perfect H, where the back to legs of the YJ cage start inboard of the main hoop. Adding in a cross brace wouldn't be triangulation, that would be bracing...but a really wise idea nonetheless.

I have my cage planned out in my head (should be coming in the next year), but I'll be crudely sketching it down here one of these days. I'll post up when it's done.
 

·
GROUND POUNDER
Joined
·
12,318 Posts
I guess I'm lucky in that, my CJ5 is a "two seater". No backseat to worry about. All I have in the rear is my fuel cell and ammo cans..etc. That let me run an "X" from the B pillar down to rear of the Jeep tied into my body mounts (custom body mounts for the 'glass body). I still want to do an "X" in the B pillar though. I flopped the Jeep last weekend and the B pillar landed square on a pointed rock. It held its shape but was dented in about 1/3 of its diameter. I'm going to patch over it and also plate the corners a little to help prevent denting.
 

·
H2 Recovery Team Member
2006 TJ Golden Eagle
Joined
·
6,699 Posts
how about turning the rear seat sideways and let them access it from the rear. you could even raise it up a bit and give them more leg room since they could stretch out onto the fender wells. just a thought
 

·
Registered
Joined
·
179 Posts
I have a question. With all this talk about triangulation and hoops collapsing when unsupported, wouldn't that make the CJ and '87-'91 YJ cage superior to the later '92 and up Wranglers? I have this argument on the YJ forum all the time. But it seems to me that the early design is a lot stronger. There is really nothing keeping the '92 and up roll bars from just folding over in a rollover, it would seem to me. Any opinions?
Buddies factory '75 bar. NOT very strong.


We spent a lot of time on this beotch too. Only had it for bout 3 months after finishing it to. Dumb box pulled out in front of him at about 40mph.
 

·
Registered
Joined
·
179 Posts
The guy with the flat top and the gash on his temple was driving and the only one hurt. Just scratches. This pic was taken a couple days after the wreck. He was driving down a 45mph zone when a woman pulled out in front of him. He swerved right caught the gravel shoulder and countered left and tried to correct and piled into the car upside down landing on the car. God was his copilot that day, and nobody was with him. This is all hear say too. My buddy had his bell rang pretty good and dosn't remember much if any of it.
 

·
Registered
Joined
·
100 Posts
Buddies factory '75 bar. NOT very strong.
CJ-5's and CJ-7/early Wranglers have different rollbars. On the CJ-5, the rollbar's main hoop is perfectly straight up and down while the CJ-7/early YJ is tilted slightly back against the support, and the supports are lower and on the side of the main hoop, not on the top, like the 5. CJ-5's also have the entire bar mounted on the wheel well. I think that the stock 5 rollbar is visibly weaker then later ones. I think even the "H" shaped TJ Wrangler roll bars appear to have better design.
 

·
Registered
Joined
·
114 Posts
quiksand said:
CJ-5's and CJ-7/early Wranglers have different rollbars. On the CJ-5, the rollbar's main hoop is perfectly straight up and down while the CJ-7/early YJ is tilted slightly back against the support, and the supports are lower and on the side of the main hoop, not on the top, like the 5. CJ-5's also have the entire bar mounted on the wheel well. I think that the stock 5 rollbar is visibly weaker then later ones. I think even the "H" shaped TJ Wrangler roll bars appear to have better design.
Any of the above mentioned will fold like a cardboard box in a upper side impact. They don't have any side triangulation. Something is better than nothing, but well designed with proper tubing and quality welds is better than just something.
 

·
Sold my soul to JeepForum
Joined
·
1,834 Posts
Discussion Starter · #130 ·
found some good info from a race car saftey spec website (sorry for the bad pic)......
-----------------------------------------------
Roll Cages for the Unlimited Division must be fully welded. Bolt-in Roll Cages are not allowed.

1. The Roll Cage must be designed and made so that, when correctly installed, it substantially reduces body shell deformation and so reduces the risk of injury to occupants.

2. The essential features of Roll Cages are sound construction (designed to fit the particular vehicle), adequate mountings and a close fit to the body shell.

3. Tubes must not carry fluids.

4. The Roll Cage must not unduly impede the entry or exit of the Driver/Co-Driver.

5. The Roll Cage must be welded to the major structure, or be part of the major structure of the vehicle.

6. A NASCAR style Roll Cage is highly recommended.

7. Door intrusion bars are required on both sides of the vehicle. A minimum of two bars is mandatory and three or more are recommended.
a. The third bar may be a removable bar.
b. It is recommended that the bars be connected in a ladder like fashion.


8. A metal roof is required and should be welded to the cage on all cars without an integral welded-on roof.
a. These requirements are applied to cars with fiberglass or plastic roofs, removable or sliding tops, T-tops and open cars.
b. The metal must cover the driver compartment and passenger compartment unless the vehicle is driven solo.
c. If the floor pan of the vehicle is not metal then a metal floor pan must be added to protect the intrusion/extrusion of the Driver/Co-Driver's feet and leg area.
1) This floor should be attached to the Roll Cage.



9. Material, Fabrication, Bracing and Installation specifications are the same as the specifications for a Roll Bar.

10.Main Hoop and Braces: The main hoop and support braces should be of the same size.

11. Minimum Tubing Sizing: The size of the tubing to be used shall be determined on the basis of the weight and speed potential of the vehicle.

Vehicle Weight Tubing Material Tubing Dimensions
-----Under 2,700 lbs.
Mild Steel 1.50” O.D. X .120 wall
Alloy Steel 1.50” O.D. X .090 wall

-----2,700 to 3,000 lbs.
Mild Steel 1.75” O.D. X .120 wall
Alloy Steel 1.50” O.D. X .120 wall

-----Over 3,000 lbs.
Mild Steel 1.75”* O.D. X .120 wall
Alloy Steel 1.75”* O.D. X .120 wall


-=*2.0” O.D is highly recommended for vehicles over 3,000 pounds.
 

Attachments

·
Registered
Joined
·
297 Posts
I want to add a full cage to my TJ and I have a few questions about it...
1. best and strongest materials to use?
2. best to build off of existing roll cage or start over?
3. I am on a budget (severe at the moment:)) cheaper to buy the front bolt on or weld on and then build on my own later? Or just do all myself?
4. I am just looking to have front bars, dash bar, and a bar connecting the two in the back for right now, anyone have any suggestions..

thanks for your help I am new to the fabbing, and building world... just trying to make a good rock crawling Jeep!
 

·
Sold my soul to JeepForum
Joined
·
1,834 Posts
Discussion Starter · #132 ·
it really depends on how much and where you wheel? If your competing in rockcrawling events then yeah you need a full on 8point+ rollcage with 2" DOM tubing... If your a weekend warrior and aren't going but once a month on mild trails, then you only need an add-on cage, welded preferrably, to complete the factory cage.

so... whats your type of wheelin'?
 

·
Registered
Joined
·
297 Posts
Weekend trail rider, i go out almost every weekend.. most trails are mild but I have been finding more nad more ones I would liek some more protection on..
 

·
GROUND POUNDER
Joined
·
12,318 Posts
Then do a front "add-on" with 1.75"x.120 DOM. Also, pick up a stick or two of additional tubing (20ft stick) and you can do a dash bar, shoulder harness bar, hip huggers (diagonal bar along sides of seat), maybe a diagonal or "X" in the main ("B") pillar to help keep the cage from shifting. Plus, you can use that tube for other stuff down the road.. stinger, exo cage stuff..etc. My buddy recently got a nice add-on kit from SW Racecars .. they used 1.75"x.120 DOM and the kit cost about $300 shipped to the door.
 

·
Registered
Joined
·
179 Posts
Big Limes Yota big brother

Little QE action.
 

·
Registered
Joined
·
179 Posts
Looks like nice work but don't these A pillars look a little , well weak?



Shouldn't they be a little straighter? Yah the dual B pillars would hold up a buss, but these "S" A pillars could calapse under load like an endo flop.
 
121 - 140 of 1133 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top