How to mount roll bar on chassis

[Bartso]

hey guys just wondering how to mount my roll bar to chassis this one i feel would be the strongest



the reason this one is here cause i saw it on someone elses roll bar but feel it would put to much stress on it


this plat will have holes in it tapped then the plate the roll is welded on to will bolt into this how should this plate be welded on i've seen it welded all 4 corners onto the chassis then just top and bottom and how many bolts shold i use this will also be supporting my exo so it needs to be really strong

[stuee]

From my limited knowledge of mechanics (what do you expect when they try to teach you two semesters in one) the second method will place more torque on the mount allowing it to break more easily. Also with the first method by cutting the pipe at an angle I think you get a larger circumference = greater welding area.

As for attaching to the chassis I think most cages are bolted on through a similar setup to what your thinking. I believe internal rollcages are mounted on 100mmx100mm plaets which are bolted to the body(floor I think). The cage can then be welded at various other points (just a small weld) just to provide stiffness.

If any of his is wrong and its pointed out I will pull it down, otherwise its how I would do it.

[Slo-Lux]

correct... the top method will result in less bending moment about the chassis rail and is therefore the smarter way to go

[J Top]

Rather then welding on a 10mm plate with tapped threads I would drill though the chassis and weld crush tubes in it ,then bolt right through.
This would use both faces of the chassis for support and no mucking round with loose tapped holes and shortened bolts.
J Top

[Bartso]

so drill say a 12mm hole put a tube through it then use maybe 10mm bolts and another plate on the back of that

[bru21]

what you have to look at to is the second tube angle at 90 odd degrees protects the cab to a finite distance being the length of the tube before the bend. the sharper the angle as in one, would fold the tube and the chassis by providing the load with greated leverage as the pipe is longer to the cabs edge. i am talking about a roll on the side. a cross brace placed correctly should make the two similar as the load is in different directions.

i would place the tube at 90 degrees and if you are worried another triangulating tube across the bend. that way you have the lower cab protection of 2 and better upside down weight transfer of 1.

you have seen mine buddy

cheers mate bru

[Bartso]

ok so maybe i should build the rear cage something like this

[toughnut]

Haven't made a drawing for you but try to picture this. I'm mounting uprights vertically up from each chassis rail to the top part of the roll bar, these will then be cross braced for side strength and will also have supports running down at an angle towards the rear of the tray to pick up the chassis rails again. The outside portions of the main roll bar will only be there for body protection and to strengthen the sliders. You could also do what hoonz has done (and what I'm going to do) and mount the sides of the roll bar to the rear of the sliders. As I said before it'll give more strength to your sliders and the rollover strength is already there if you mount your uprights off the chassis rails