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post #1 of (permalink) Old 08-28-2000, 12:34 PM
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more rollbar analysis

Here is what the bar looks like with a 20,000 lb force placed directly on the upper "X". Looks like a vertical bar from the top of the back "x" to the upper portion of the rear main hoop might be needed.

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post #2 of (permalink) Old 08-28-2000, 12:49 PM
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Re: more rollbar analysis

Very interesting . Wonder what the result would have been if there were gussets at each corner of the front and back hoops ? Is it possible to do this and show the results ? Keep up the good work !


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post #3 of (permalink) Old 08-28-2000, 07:23 PM
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Re: more rollbar analysis

Not unless you plan to drop a semi on the roof!

It gave where I though it would.
The upright bar in the back, and an upright bar in the center of the roof 'X' if you decide to drop an semi on it, and you don't want it to deform...

I'm assuming you are using 20,000 Per Square Inch, all over the cage...
How may square inches of tubing are shown in that graphic?
..... See what I'm getting at.....?......

You will have maybe 5,000 Per Square Inch at the corners when it turns over in a slow roll...
On a slow roll where the is no velocity involved, the maximum pressure can never exceed the weight of the vehicle (which I'm figuring at 5,000 lbs loaded).

What I think you are doing is smacking it with 4 times the vehicle weight on EVERY SQUARE INCH if I'm reading this correctly...
I'd say some distortion should be expected, but you didn't even have cabin failure!!

Pretty good design Jesse!!!!

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post #4 of (permalink) Old 08-29-2000, 07:06 AM
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Re: more rollbar analysis

I am hitting it with a 20,000 lb distributed load over the length of the top "x" portion.

I agree, I think the 20,000 pounds is excessive. But if I ever get that wild hair up my ***, and end up driving out to tellico, or out west, and leaving the rolling elevation changes of the midwest, it would be reassuring to at least be confident that the bar can stand a fall off of lion's back.

Just kidding., what I am saying is that if I am gonna build a cage, I am not gonna mess around. The 20,000 pounds, without gussets, ought to hold up to just about anything I can think of.

I have been doing alot of thinking latelyt though, and I think I need some sort of side protection. Preferably removable, and that doesn't prevent me from being able to get into the jeep. I will let you know when I come up with a good idea. You got any ideas guys?


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