roll cage - weld or just bolt it on?

[cisco]

i asked the same question in a different thread- but the topic has shifted a little - i have new questions now..

1. is it best to weld the cage in several places to the frame (front, middle, rear)?
2. is it OK to have the cage welded only in the middle, or at one end or the other?
3. is it effective, or worth itstalling one at all, if its only going to be bolted to the body?

-im hearing replies of all ranges.

the cage is going into a stock bronco. no plans to do any major off roading. have kids that will be riding in the back.. highway driving, probably no more than 60MPH. might add a slight lift sooner or later, but right now its stock.

thanks!

 

[Broncobowsher]

You are going to get so many different answers to this depending on who is giving there opinion I doubt you will figure out what you want. So I will start

1) If you are getting ready to roll the truck in a movie, this is the way I want it done. Massive solid structure. who cares about body flex, road noise, vibrations or servicability. This is perfect for someone wanting the ultimate in protection and the ability to beat the snot out of it and throw it away when done.
2) No, body and frame flex and move around. Those rubber mounts that are between the body and frame are there for a reason. Half anchoring it to the frame will tear out something.
3) This is generaly just fine. Considering that most street rolls are usually just a flop on the side from being tripped on a curb or something. While not the protection of a nascar cage, better then none at all. This is providing the body is still in good shape. Bolting it to a rust bucket isn't going to do much good.
Mine is just bolted to the sheetmetal. I wheel it fairly hard. Prior owner rolled it once and when I got it there wasn't even a cage in it, just a single hoop roll bar, probably put in after it rolled. The ability to unbolt the cage turned out to be a great plan. When I was building it my friend who had the welder was just going to weld it to the floor. Later I plulled the cage to remove the dash to rewire the truck. Bolt in was good. If you still want frame tie ins, at least put bushings in.

Be realistic in your needs. Someone will probably hype in that you can't be safe enough. In that case just go buy a Volvo with 8 airbags and never leave the driveway

 

[Steve]

Obviously a cage connected to the frame will be the safest in a violent roll/crash. However, you should not simply weld the cage to the frame as that will pretty much defeat the purpose of the body mounts. There are ways to attach a cage to the frame with bushings, but that's not easy. As long as your tub is in good shape, I'd bolt it to the body by sandwiching the floor of the tub between metal plates.

 

[trailpsycho]

Cisco-

Nothing on the Bronco is ever "DONE", therefore, "everything" needs to be modular-able to be bolted and unbolted (with the exception of bedliner, paint). The cage should be fully welded (no bolts holding IT together) and welded to 4x6 1/4" steel plate. These plates are then bolted through to the floor. Most people go this route...some weld the plates to the floor( mine was done this way by the race car guy that I had make it 12 yrs ago--I didnt know any better at the time. He brought 2X4 tubing off of the frame at an angle, then the main hoop right off of that through the floor. The rear tub mount was welded to plate that was welded to the floor--no frame tie in there. So only the main hoop was tied to the frame).

To take it a step further and make the cage stronger/safer, it would be smart to bring tubing off of the frame towards the cage's floor points and again use 1/4" steel plate as the lower mounting point--effectively sandwiching the body between the cage and cage/frame tie in. Alot of people when doing the cage tie-ins include a poly-bushing set-up somewhere between the frame and where the lower tie-in plate mounts to provide some ability to flex the body.

I always thought this was the only way to go, but when I did my 6-point tie-ins, it ended up not happening. To explain--I thought that the direct frame tie in was what always made my truck ride harsh, but this ended up not being the case. When I replaced the body mounts (WH 1" lift-mount), the ride improved. At the same point, I also cut the roll bar where the tubing went through the floor--I had to b/c of the 1" BL aspect of the new body mounts. I used 3 pieces of 1/4 plate in my case, 1 for the main hoop on top of the floor and 2 (1/2" total) pieces underneath to make up the 1" from the lift. After it was all bolted together it was essentially a rigid set-up, but I noticed no harsh ride, no flex problems. Shortly after the BL and I also had the cage completely redone--already in the plan. The rear section from the hoop back was removed and new tubing was bent, a front section was also added to give a very sturdy family style cage. He also connected the front and rear sections to the frame via 1 5/8 0.134 tubing...he left the main hoop alone (its already very beefy). All of these tie in points use ~4X6 1/4 steel plate under the body and on top and are tied together with 4 pieces each of grade 8 hardware. There are always multiple ways to do anything, but this worked for me and I am very pleased. Hopefully, it will never end up "turtled"...but if it does, my butt is sitting on seats attached to the cage, not the floor--yet another thing to consider. You want to have your seats and harnesses BOTH attached to the either cage or to only the truck....it would be best if seats and harnesses are attached to the cage. If by chance the cage seperates from the rest of the truck you dont get choked or filleted by the seat belt.

Back to your questions, I would recommend not welding the plate to the tub, bolt it down and use 1/4" plate below the floor (as well as the top) to help reinforce the tub...actually a very good idea...then if you ever decide to do a frame tie-in, just connect it to that plate already there. Its up to you about the seats. As with all things Bronco, this is a snowball rolling out of control down a really big hill, only you can decide how big you want it and where to stop. Good luck with your choices.

John

 

[cisco]

well, now ive heard that U bolting the cage to the frame would work..

as it is right now, unless the fabricator advises otherwise- im going to bolt it to the body. i hadnt thought about removal, and i have plans to rewire - so maybe later i will have it welded in, but for now i think im going for a rear cage.

 

[rob wilson]

I just spent some time at Protofab this afternoon pondering the same thoughts. I was looking at having them bend the front hoop legs forward so they would go through the floor board ahead of the existing location and avoid cutting through the stiffener they would be bolted through.

After much discussion/deliberation with Mike and Keith, looks like I'm going with the stock cage they sell but adding the door bars and perhaps a bar across the middle hoop at floor level.
My thinking is:
1. What I was worried about was relying on just the four/six pads that bolt to the body to support the entire load
2. Using the door bars and potentially the rear bar mentioned, even if the pads should punch through or deform on severe impact the bars will distribute the force across the entire floor.
3. There is no easy way to stub out from the frame to the hoop feet and when you do, it's close to a foot out from the frame. If the hoop takes a good hit, what keeps the frame from twisting?

I'll bolt my belts to the bar since I doubt that the bar and body would seperate.

So, bring it on, what are the problems with this plan??

 

[El Jefe]

what size bolts is everyone using? (those who bolt the cage to the body)

 

[SaddleUp]

what size bolts is everyone using? (those who bolt the cage to the body)

I believe mine are 3/8 Grade 8 bolts. Be sure to sandwich the body with a 4" square by 1/4" thick plate. That is what many racing sanctions require for body mounted cages. Also never weld the cage to the body even if it connects to the frame.

As to the frame vs. body debate I may eventually tie mine to the frame but for now I'm bolted to the body with sandwiched plates. (In the 3 rolls I've been in frame mounts wouldn't have made any difference and none of them had as much protection as I have now) I've additionally made my cage a full cage not only above but underneath as well. The seats and seat belts are both mounted directly to the cage so that in the event it is ever ripped loose from the body the occupants stand a better chance of being protected by the cage. I wouldn't count on it protecting me over a 500 foot cliff though. (Nor do I think a frame mounted cage would either)

 

[BroncoMark]

What do you guys thinks of this set up? It's welded to the body with plates at the floor, and welded to the body behind the doors (hard to tell, but they are boxed top and bottom). Good design?

 

[DonsBolt]

What do you guys thinks of this set up? It's welded to the body with plates at the floor, and welded to the body behind the doors (hard to tell, but they are boxed top and bottom). Good design?

I am not a fan of welding the plates to the floor, unless you have bigger plates under the body. When you weld to the sheet metal as the body flexes the welds can become a week point, and the metal can crack along the welds,

If you have bigger plates under the the body, it might be ok.

 

[Socal Tom]

What do you guys thinks of this set up? It's welded to the body with plates at the floor, and welded to the body behind the doors (hard to tell, but they are boxed top and bottom). Good design?

I think bolting with a plate underneath would be more likely to survive a crash than welding to the body like that.

Tom

 

[Socal Tom]

i asked the same question in a different thread- but the topic has shifted a little - i have new questions now..

1. is it best to weld the cage in several places to the frame (front, middle, rear)?
2. is it OK to have the cage welded only in the middle, or at one end or the other?
3. is it effective, or worth itstalling one at all, if its only going to be bolted to the body?

-im hearing replies of all ranges.

the cage is going into a stock bronco. no plans to do any major off roading. have kids that will be riding in the back.. highway driving, probably no more than 60MPH. might add a slight lift sooner or later, but right now its stock.

thanks!

For normal off road use, people have been using the bolted to the body ( with plates underneath to form a "sandwich" for years. That connection is stronger than the bolts holding the body to the frame, so its quite adequate for what you may encounter.
Some race safety requirements ( best in the desert I believe) even allow that for racing.
At a certain point I think its more important that the seats, and seatbelts stay in the cage, than the cage stay on the frame. What you don't want is the seats attached to the cage and the seat belts attached to the body so that if they seperate the passengers are torn apart.
Tom

 

[SaddleUp]

What do you guys thinks of this set up? It's welded to the body with plates at the floor, and welded to the body behind the doors (hard to tell, but they are boxed top and bottom). Good design?

Sheetmetal gets brittle in the vicinity of welds. This is compounded by twisting and flexing of the cage and body which work hardens the metal around the weld even more because it can't flex there at all. It's an absolute no no in the racing circuits.

 

[MattMoe]

Has anyone been a in a side impact car wreck with a caged bronco? Did the cage help? Would any method of attachment add structure to help save you with your doors off in a side impact?

 

[welndmn]

Bolting to the body is just for 90% of the people, unless your floorboards are rusted.
Tieing to the frame is the best, but can also be added down the road.
I had a few flops (including one 40mph) with it only bolted to the body, no worries.

I am not a fan of welding the plates to the body, for the same reason SaddleUp said, but then, my rear bars are now welded to the body, then tie into the frame. While not ideal, it the only way it fit, and it works just fine.
My other front legs of the cage are all tied into the frame as well.

 

[68 Broncoholic]

If you want to stay away from connecting to the frame you could always add more bars. Add one at the rear hoop right at the floor surface going from one leg of the hoop to the other. Then some across each door way on the floor so it ties in the rear hoop to the front legs. Then add some inwards for seat mounts. Same on the rear hoop and even the trans tunnel if you have a cross chicken bar. This way you have to crush the entire floor boards before it comes down on you. If you plan on some serious wheelin then you might as well tie into the frame.
A buddy that I wheel with has been in many roll overs and he's now building his cages to release from the body in a bad roll over. This way he rides inside his squirl cage ride until he comes to a stop. Of course this isn't going to portect him from branches and rocks that poke thru durring the ride.

 

[rellimgneb]

Why would you ever weld your bar to the body? There is ALWAYS a reason when you have to pull your frame out to do something. I'm just going to be bolted to the body. I have a set up along the lines of saddleups with seat mounts attached to the frame so I didn't see any need to tie into the frame. My cage in my other bronco is just bolted in too and I am eternaly thankful it was never welded in by some misguided soul because I have removed and reinstalled it four or five times and need to do it again when I make it to working on the other bronco.

 

[SaddleUp]

One thing to keep in mind for anyone going to the frame. Your going to want cross bars at the bottom inside the cab area. That way if the cage punches/pulls through the body then it will help keep it from squashing the occupants. Mounting the seats/belts to the cage effectively does the same thing since you need lower cross bars to mount to.