Hi all what metal and what thickness do i need to make a roll over bar with 

Got to be stainless 

a show cage or a proper one. A proper one will be cold drawn seamless tubing around 45/50mm thick wall 3mm or you can also get alloy/stainless show ones made

1 1/2" nominal bore BS1386 blue band tubing is what's generally accepted as being good for roll cages - it's what we use on landrovers.

Not too expensive either.......

Stainless cages look good but are purely for show. The question is what do you want? If you want a proper cage, then the mounts need to be up to it too.....

Jon

Made out of any thing its only as strong as what you bolt it to 

thanks for the input 

What ever cage is used it should always be bolted through the fibreglass tub as well as the floor pans.

Basically Fibreglass is really strong in tensile (ripping) strength - try drilling a hole in fibreglass, putting a bolt in it and then try ripping the bolt out sideways !!

Also try and link back to the chassis (not floorpan) fixings too if possible

Mine bolts through the chassis at the sides and front fittings with the two rear supports bolting through the glass at the back with large spreader plates both sides and an angle iron bracket to the chassis.

Havent got one showing the fittings but the photo gives you an idea of where it is bolted.  Made of stainless tubing, various diameters cant remember the thickness.

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Cant get photo link to work for some reason so here is the URL


Hope that helps
Dave

TBH if youre just planning a single hoop then they can only really be considered as a 'show bar' anyway. If its purely a street buggy then as long as you drive sensibly and stay sober thenyoure highly unlikely to actually roll it anyway so constructions not that critical. Anything less than 2 inch dia is going to looktoo thin, esp on a lwb buggy. Original GP roll bars were bent up from 2 inch exhaust tubing so anything thicker would be a bonus.