I posted this in the 4x4 Tech, but haven't gotten any responses.

I currently have the Davesport cage (1.5" .120 ERW). I have since added tubing to tie the seats into the cage and will be tying the cage to the frame at the 6 base points.

I'm going to be adding two tubes down the center from the front hoop to the main hoop for more bracing and somewhere to hang my CB from.

I'm also planning on putting in a diagonal brace on the center hoop from the driver's head to the passenger's floor. The problem is that the center hoop is just close enough to the driver's seat that I can't run a straight tube from the top. If I do, it will be very easy to wind up hitting my head on it.

Here's the question...

What way would be better to go with? Putting a slight bend in the tube to go just far enough behind my head and still running it to the top of the hoop? Or running a straight tube that goes doesn't go all the way up (just below the driver's head)?

Here's a pic that might give a little bit of an idea of what I've got.
http://home.attbi.com/~rokzuki/pics/cage6.jpg

http://home.attbi.com/~rokzuki/pics/cage7.jpg

I'm no guru, but what about putting the diagonal brace from the driver's floor to the passenger's head?

Maybe that would be backwards...

How about running it horizontally just below the driver's head, and then run a vertical straight up the middle to the top of the hoop?

Originally posted by dangerber
I'm no guru, but what about putting the diagonal brace from the driver's floor to the passenger's head?

This would solve it from hitting my head, but a tall passenger might hit theirs.

If anything, I will be running a straight diagonal about 6-12 inches low of the bend. This isn't quite as good as having it meet at the intersection, but it is better than nothing and will help keep the hoop from caving in the event of a hard hit on the bend.

Maybe something like this MM

Or this

This is what I'm still trying to figure on my buggy hmmmmmm..... a few good ideas here.

Mark

we went like this pix..

my.02

If you can brace from just below the bend right behind your head to just above the floor plate behind the pass. seat , i'll be 10 times stronger than what you have now...

If you decide to go with the "V" design, it won't be as strong as a complete brace from corner to corner, stonger than nothing YES, but your transfering all the engery to the middle of a span of straght tube.... The upsidedown "V" is even less strong for a side roll....:(


:bender:

Originally posted by Tin Bender
my.02

If you can brace from just below the bend right behind your head to just above the floor plate behind the pass. seat , i'll be 10 times stronger than what you have now...

Thanks TB, I figured that a full diagonal would be the strongest. I just need to see how close to that bend that I can get and not be able to end up hitting my head.

Now I just need to start measuring and notching that tubing and get this thing done.

Not the best pic but were at work.

Don't listen to the :bender: boys they don't know what they are talking about:D;)

Help me out with this. It looks to me like the common practice shown in number 1 would provide little protection for a passenger to a force in the direction of the green arrow on the right. Seems like #2 would be much better.

I ordered a Petroworks cage and it should be here next week. Here ia what I am going to do for sure. I wont know how much headroom I have behind me until it gets here.

Just for the sake of discussion. Is this much better than nothing or a bad idea?

Shrock:

Are you going to keep it all bolt-on, except for the pieces your adding or are you going to weld it all up??

Thanks

Originally posted by Shrock
I ordered a Petroworks cage and it should be here next week. Here ia what I am going to do for sure. I wont know how much headroom I have behind me until it gets here.


I would do the one across the dash , but scrap the two at the rear. I would add a diagonal on the main hoop, preferable from drivers lower to passengers head. I would also add a diagonal from main down towards the rear.

A cage is a bunch of popsicle sticks untill it is braced .

Originally posted by Shrock
Just for the sake of discussion. Is this much better than nothing or a bad idea?

Bad idea, does nothing but give you a place to knock yourself out on, and does more damage to the main hoop if you do roll over.
This adds no strength.

I'm inclined to weld the whole thing up, but Gary at Petroworks warned me that I would not be able to remove it if I welded it. I'm not sure how much I care about that except the way this particular cage wraps around the dash might make it impossible to pull the dash. That would be a problem if something in there croaks.

It seems that if I left the back hoop bolt on, maybe I could unbolt it and slide the rest of it back enough to get the dash out.

So basically I'm not sure yet, but I will probably bolt it and weld it unless it looks like it could cause major grief in the future.

Originally posted by mudlite


Bad idea, does nothing but give you a place to knock yourself out on, and does more damage to the main hoop if you do roll over.
This adds no strength.

Why is it a good idea for the front hoop then (bar over the dashboard)?

In the engineering world, the function of a brace is to help the frame maintain its shape, and not to carry loads per se. Technically, braces should never be subjected to bending forces, only tension and compression. This means that the ideal brace (for this application anyway) always goes from one existing joint to another, and doesn't create a new one. With welded steel, you can get away with all of the above because any of these added brace elements would help resist deformation of the main cage.

The true cross brace is the best by far, but it can be a PITA especially on the noggin :eek: . All of the other diagonal bracing ideas will help considerably. The designs which just make smaller boxes though aren't nearly as efficient.

I am glad to hear that you are tying the cage into the frame, cause without that, the bracing is serious overkill. The frame would likely rip off the body long before it deformed to the point of smushing the occupants.

Originally posted by Shrock


Why is it a good idea for the front hoop then (bar over the dashboard)?


You’re going to have a hard time putting a dash bar in the petro cage. Just because of its bends in the front down tubes. If you wondering why, it's because of the instrument cluster. The best bet is to go under the dash on this cage, and modify the radio box (remove).
If I had no bender at all? 1st I would get a Dave cage:flipoff2: but if I was forced to use the petro cage I would also do the following red and green to the cage (without a bender)....at the bare minimum.

Originally posted by Shrock


Why is it a good idea for the front hoop then (bar over the dashboard)?

I think what John meant to say is that it does very little in comparison to the other options. In the front it is the best you can do and still see out the windsheild.

The big deal is to make as many triangles as possible and as someone else pointed out - keep the members in compression or tension. The triangle is the strongest structural shape.

The reality is, depending on the intended use of the truck, you will have limited options. What's the point of having a mondo cage if you can't use the truck they way you planned? All cage and no room to store gear as an example. Sounds like a cop out? Gotta define your priorities. A competition rig is a much different beastie.

Reality is, with any of these cages if you really needed the super cage and the strength of it, by the time you reached the bottom of the mountain in your roll the vehicle might not have collapsed but everything inside would be reduced to a pullp (including passengers).

What the fawk am I trying to say? Install the cage you've got, reinforce it where you think it needs it for your application but don't make the truck useless as a result. I like what billy4rest posted in his last image in particular. The lowest hostizontal bars will keep the cage from pushing through the tub.

Originally posted by Bill4rest



You’re going to have a hard time putting a dash bar in the petro cage. Just because of its bends in the front down tubes. If you wondering why, it's because of the instrument cluster. The best bet is to go under the dash on this cage, and modify the radio box (remove).
If I had no bender at all? 1st I would get a Dave cage:flipoff2: but if I was forced to use the petro cage I would also do the following red and green to the cage (without a bender)....at the bare minimum.

add a lateral on the main hoop, dash bar is real good idea, and door bars are cool.:)

the rest is kind of over kill.

Originally posted by fatkid


add a lateral on the main hoop, dash bar is real good idea, and door bars are cool.:)

the rest is kind of over kill.

I'm 99% sure that the dash bar will hit the wheel or be too high in the winshield (if not bent), So I'd go under the dash without the top blue bar. I don't think it is over kill when you take into the fact that the cage has a gazzilon bends in it. and held together by bolts, plus if you use 1 1/4" .095 tube for the gussents you'll be fine.

Originally posted by fatkid


add a lateral on the main hoop,

Where would you put this (how hig/low)? By lateral, do you mean straight across as apposed to a diagonal?

Originally posted by Shrock


Where would you put this (how hig/low)? By lateral, do you mean straight across as apposed to a diagonal?



lateral=diagonal
Horizontal=sideways
Vertical= up and down:flipoff2:

Originally posted by Bill4rest




lateral=diagonal
Horizontal=sideways
Vertical= up and down:flipoff2:

if you need to know what way down is.....hold a wrench out at eye level, and drop it.......follow it..."that way is down:flipoff2:

Originally posted by Arizona Zuk


if you need to know what way down is.....hold a wrench out at eye level, and drop it.......follow it..."that way is down:flipoff2:

I agree with Dave but hold the wrench over his head and let go,
that way he gets the meaning of gravity, and Horizontal when come too.

Originally posted by Rockrat


I agree with Dave but hold the wrench over his head and let go,
that way he gets the meaning of gravity, and Horizontal when come too.

Classic:laughing:

lateral=diagonal, silly me, I though it meant side to side. Oh wait it does mean side to side.

Any good tricks like this on figuring out left from right?

:flipoff2: :flipoff2: :flipoff2: :flipoff2: :flipoff2: :flipoff2: :D

Originally posted by Shrock
lateral=diagonal, silly me, I though it meant side to side. Oh wait it does mean side to side.

Any good tricks like this on figuring out left from right?

:flipoff2: :flipoff2: :flipoff2: :flipoff2: :flipoff2: :flipoff2: :D
ONLY EXAMPLE I CAN THINK OF
Break your lug nuts loose jack the truc up grab a good 4way
and give it a good spin just make sure your head is in the way you should be hit on the RIGHT temple causing you to fall to you left side. trust me hurts like hell even after youve had a few beers in ya. Also your rock runners look good!

Originally posted by Shrock

Any good tricks like this on figuring out left from right?

:flipoff2: :flipoff2: :flipoff2: :flipoff2: :flipoff2: :flipoff2: :D


Put an -L- on your left hand and a -R- on the right
.
.
.
.
.
.
do the same with your shoes


























:flipoff2: :flipoff2: :flipoff2: :flipoff2:

Originally posted by Shrock


Where would you put this (how hig/low)? By lateral, do you mean straight across as apposed to a diagonal?

sit in your rig and get an idea where you head sits, you don't want the brace to much of an interferance.:)