Roll Cages... multiple threads merged

[ChaseTruck754]

Removable cab I get (well if cage is welded to it and all comes off together), removable cage from cab I don't get.

[Rmc]

Removable cab I get (well if cage is welded to it and all comes off together), removable cage from cab I don't get.

Same here.

[steve-oh]

Cab and cage would be one, just the bed cage would be able to be removed seperate from the truck, replacing bed from damage is my thinking

[steve-oh]

rmc, i like the idea of the tabs and clevis....where the tube goes threw the cab would you weld it to the cab ? for that matter the cage inside are you welding the top side plate to the cab ? was going to use a plate on the top and bottom with four bolts that would make it removable if the cab needed to be seperated from the truck.

I was talking about the bottom of the cage where it mounts to the floor with the plates

[ChaseTruck754]

Ahh, much easier to do and much better layout IMO.

So yeah, to reacap:
Tube above the window with bushing or solid mount out back.
Plate the cage into the body using silicone bronze rod.

As for cage attachment to frame - bushing or solid is up to you. I personally like the tubes from the cage to land on plates that bolt to the frame. A bit more work, but very clean if done right. Check out SI Motorsports for this setup at a high end level.

Whatever you do mount wise from cage to frame (solid or bushing) then do the same from cab cage to bedcage above the window.

I like what Tom did on the Baja250 with a plate that bolts together at this junction. Takes a bit more work, but is CLEAN and solid.

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[Rmc]

On the floor do caster plates and sandwich the floorboard, j tube attachment to the frame. These j could be made bolt on at your discression. The thinking on mine is if I bend the frame badly i can swap frames. That or right over the top of the frame rails the sandwich plates could be welded to the frame on the frame side via a short verticle tube with the caster plate on the top and add additional support to the cab. I'd suggest solid body mounts for this approach. If keeping rubber mounts just j tube attach and fill the gaps in the floor where the bottoms pass through and with sikaflex to allow flex without ripping.

[Rmc]

Steve Your pic was the first thing style wise I though of but was worried he wouldn't be able to match the roof radius in the plate bends it would have to be a matching pair radius wise. If there were fat gaps at the sandwich it would look bad. But I guess they could be filled with caulking to look cleaner. If you worried about fit n finish radius em or find a flat spot. I would also use delrin not poly if you choose the bushing style instead.

[Travisfab]

I've never been a fan anything bolt on chassis wise. I'm not saying these methods don't work, but for me, if I roll doing 80+ mph I want to rely on my welds, not grade 8's. My opinion is that welding your cage to plates welded to your frame is the best method.

Think about being cart wheeled 15 feet in the air at freeway speeds in a 5,000+ pound truck.

[BDKW1]

I would rather rely on the bolts. I have seen trucks with bolt on cages roll. The bolted intersections hold up better than most welded connections as they are usually done very poorly.

There are plenty of vintage pre-runners out there with bolt on cages that have been used and abused for decades without issue driven by some of the best in the business.

[Rmc]

Actually you hit the nail on the head Travis, most rule books state the seats must be attached to the saftey cage structure. In the event stuff starts breaking away from the frame the cage and driver are held within that structure. Keep in mind he said its not for racing though. But I totally agree.

On my last truck everything was welded, floor plates were c notched and fit over after cages as welded to the frame, then welded to the floor and plates. At the same time that's why I keep saying use glue because the weld all the way around at the floor level weakens the tube. Basically your taking the heat treat out of the tube. That's why they suggest flame annealing all joints. This process is supposed to normalize the embrittlement zone near the heat effected regions. This is another reason why dudes tig vs mig lesser heat effected zone. I know I know this ain't NASCAR lol
Just trying to pass along some of the stuff I've been reading.

[Rmc]

I guess what I'm thinking is welded frame joints to bolt on floor plates.

[Travisfab]

There are plenty of vintage pre-runners out there with bolt on cages that have been used and abused for decades without issue driven by some of the best in the business.

If you never roll, your cage will last forever.

[cs_drums]

My thoughts are this. Worry about whats gonna happen during the roll over and make that a priority first. Id rather have everyone ok then worry abuot haw hard it is gonna be to fix it. Personnally I think once you decide to cage it the frame and cage become one unit. In the event of a roll new fiberglass and reskin the cab. Nothing is gonn abe easy about the repairs if you roll it.

[BDKW1]

If you never roll, your cage will last forever.

Not true, I've seen plenty of the "outrigger" style cage mounts rip chunks out of the side of the frame with normal use. Any time you weld a tube 90* to the middle of the frame then hang a cage a foot out on it, your going to have issues.

[cs_drums]

If you never roll, your cage will last forever.

Not true, I've seen plenty of the "outrigger" style cage mounts rip chunks out of the side of the frame with normal use. Any time you weld a tube 90* to the middle of the frame then hang a cage a foot out on it, your going to have issues.

It does make me cringe when I see them done that way. I know there are several well built trucks that utilize that style but its not my cup of tea.

I think people have funny priorities. Adjusting cage design in trade for comfort. Like I said, not wrong just not the way I think personaly.

[ChaseTruck754]

outriggers can work - but I like them with a frame tie in as well to spread the load

Crappy pic, but may give the idea. Each one of the tubes come down vertically on the outrigger & then also angles in to the top of the frame.

[Rmc]

I appreciate what you guys are saying in a theoreticle sense but I think as far as the bottom of the a pillar a j tube type attachment is inevitable. Unless outriggers are fashioned there's no there way to keep your feet inside the structure. Sure you can do some kind of angle but at the end of the day all designs lead to the same effect being tortional load upon force transfer to the frame. There's no way to stop the leverage twist unless the frame rail spread is widened. In my particular case I have no worries because there will be 10 points of contact with the body and 6 to the frame. Keep in mind this is just added security not a race car. I think solid joints and good fit up are far more important the a j tube to worry about.

[ChaseTruck754]

Yes, but a single point of "torsional load" placed on the vertical face of the frame is actually acting in shear. The tube hitting the top of the frame like this combats that by distributing a portion of the load to the TOP of the frame.

The driver's foot area is the tough place to do this like you mention, but people do that tube in front of the fire wall or body mount to make the room work.

[Rmc]

Word.
My plan yet still in shear is the make a 2 pointed foot/ j tube concept for the a pillar lower attachment. The front just like you said will help in impact force distribution ( well I hope anyway)
The seat brackets, and floor bars will help reduce the shear as well.

I think a good rule to follow is make all potential impact points divisable by 3 to ensure force distribution, and connect on top of the frame when ever possible just like what you guys are saying.

[steve-oh]

Rmc, I like how you went threw your dash on your bronco, being able to use all the factory dash and will be doing the same for sure