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full cage and body flex

Discussion in '1973-1991 K5 Blazer | Truck | Suburban' started by four_by_ken, Mar 8, 2002.

  1. four_by_ken

    four_by_ken 1/2 ton status

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    Will mounting a full cage help control body flex?

    Thanks
    Ken H.
     
  2. marv_springer

    marv_springer 1/2 ton status

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    Yes!..... even if the cage is not frame mounted.

    Marv
     
  3. Grim-Reaper

    Grim-Reaper 3/4 ton status Author

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    Ohhh yeah. My body would flex so much that my dome lights would come on and doors would jam. With the full cage that's pretty well gone.
    Fair warning...full cage that is mounted into the corners by the gate can take a rust weakend tail pan and finish it off. The cage is only as safe as the floor it's mounted to. You have to fix any rust problem. If you don't and you go over it will drive the cage right through the floor and not do you any good.
     
  4. Stephen

    Stephen 1/2 ton status Moderator Vendor

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    That's one of the major reasons I first put in my cage. My half cab roof was making oil can noises when I twisted and I have pics of a HUGE wrinkle in the sheet metal up there. At that point it's not too long till it starts coming apart. For best effect, tie it to the frame through the floor boards. 2nd best would be to tie it to solid floor as near the body mounts as you can. That can get in the way of the cargo which is where you start getting into the tricky fab work or compromising something.
     
  5. four_by_ken

    four_by_ken 1/2 ton status

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    I got lucky... nice body from Georgia. No rust. Perfect place to start.

    No, where is the saws-all so I can make these tires fit. /forums/images/icons/smile.gif

    Ken H.
     
  6. four_by_ken

    four_by_ken 1/2 ton status

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    I would like to get the cage in before I really twist it up(the body that is). I would like ot go to the frame, but might just end up being the body.

    Just dont know where to punch the holes in the floor to mount it to the frame. Maybe I will go to the frame instead. Not sure.

    I want my suspension to flex, not my body. /forums/images/icons/smile.gif

    Ken H.
     
  7. juanblzer

    juanblzer 1/2 ton status

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    There does seem to be some division between those who swear on frame mounted cages on blazers and those who say it is not necessary. The guy who fabbed my cage, Randy Ellis www.randyellisdesign.com, mounted my cage right next to the body mounts. He said that with my seats mounted to the cage, there is a safety cell to protect in a rollover. I've contemplated tying the cage to the frame even though he said this. I constantly "pick his brain" about mods and reasons for mods. He's very knowledgable. I've asked other fab guys and they say the same thing... "it's not necessary." My cage is built carefully and tightly to the inside of the cage and removable top areas. It is so close that I have never hit my head on it. The door bars do make ingress/ egress a little more cumbersome but that's a price I'm willing to pay. Just my two cents.
     
  8. Michael

    Michael 1/2 ton status

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    Hey Juan, that Ellis site is too cool...thanks for the link!
     
  9. Grim-Reaper

    Grim-Reaper 3/4 ton status Author

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    When I made my cage I was in the process of replacing the tail pan. Since I don't run a stock gate I replace my tail pan with a 7 inch wide peice of C-Channel. My rear legs sit on it. My front and center legs sit dirrectly over the main body suports. If I roll this should be enough to keep the cage from getting driven through the floor. This is the way to mount a cage if you dont do like Stephen recomended and go to the frame.
    There is enough room in the rear that putting a 2 inch peice of c-channel or box between the frame and the bed is easily done. Then put some backing plates on the end where the legs of the cage will bolt through it. If you should have a roll then this bar will hit the frame and suport the weight of the truck shoudl the body start to fold. Not as good as a solid mount to the frame but the next best thing.
    Doing this to the front mounts would be nearly impossible but the frame is wider in that area and the cab mounts are out board of the frame. Straddling that cab mount will give you a good solid mounting point. On the 78-91's the second cab mount is the same design. On the 73-77 the cab mounts are inboard. I'm looking at adding a brace simular to the tail pan set up. Should be plenty of room since I dont' run rocker boxes. might get a little tricky if you have rocker boxes.
    Now a word on mounting and backing plates. DO NOT MAKE THEM THE SAME SIZE! if they are the same size they they will act like a shear and can cut through the floor. Top should be a little larger than the bottom. You should also add a shim to deal with the ribs in the floor. Crushing the ribs flat will weaken the floor so take the time to cut some shims to fill that gap.
    I really hate these cages that go to the top of the fenders in the rear. that fender has no real structual support. If your not running front legs and just the kickers to the top of the fenders...forget it. That bar will fold back and crush the fender wells like a beer can if the weight of the truck gets dumped on the bar.
    Just take your time when building or shopping for a cage. If your looking for a pre fab cage pay attention to where the legs mount. The Smitty hoop and front legs are not a bad design. they mount where they should. However their rear kicker legs go to the top of the fenders. Taking the time to go all the way to the rear corners where you can take advantage of the strength of the tail pan would be worth the trouble. Another option, if getting the tube bent for this is 100% out of the question, is buy a second main hoop from Smitty and mount it in the rear.Then you can run straight stringers between the hoops and a straight diagonal bar for a kicker between the hoops. As long as you have a hack saw, grinder and a welder you could do this without having to bend anything.
    You hope that you will never need it but if you do roll your truck the cage is only as safe as you make it. Putting a well designed 10point cage to a rusty floor isn't safe. Make sure your mounting points are solid.
     
  10. Twiz

    Twiz 1/2 ton status

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    On my 74 Jimmmy, with a full-top and rocker boxes.
    The section where the floor-board and bed come togather, looks like it's pretty strong. It should be, since the body mounts bolt to it, and it's has -U- channels that are about 5 or 6 inches away from eachother. Plus, the B-pillers right there too, I think I'm just going to bolt it too that, and try to catch some the the factory bolts in that area.

    The front and rear legs are a different story, not sure what to with those. (C-channel probably, thats a good idea Grimm)

    When I bought mine, it had a Smitty-built cage in it allready. The hole cage looked like it was moved back and the legs were about 6 inches away from their "ideal" location, this was to clear the windshield frame and dash. Thats something to keep inmind, if someones is considering getting a Smitty-built cage. It's a nice cage, but needs some work to really efective.


    It really stiffens up the body. I pulled the cage out, and while testing out my suspension in the garage. I busted up my top, by the rear glass, It looks like the side-glass is about to pop too. It's pretty ugly looking when flexed out.

    If I ever get a Digital cam, I'll snap some shots of it. The frame and body- flex gets pretty wild with our Chevys.

    I'm totaly convinced, We need to have cages installed, not only for the roll-over safty thing, but just to keep the glass intact too.
     
  11. ChadH82

    ChadH82 1/2 ton status

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    It seems to me if you have a cage with the seats and harness attached to it you wouldn't have to tie it into the frame. Even if the roll cage and the body seperated you would still be hooked into the cage. Unless you landed on a rock that could come through the cage or something I would think that you would live. I guess the bottom line is that tying to the frame is the absolute safest. Any thoughts?
     

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