roll cage tube thickness and tube size

does anyone no the best size tube to use, for a tight fit but not to bulky but still strong enought for a roll?
would 33 mm 3mm thickness be ok?

pictures of jimny cages would be great or if any are for sale

We would recomend a minimum of 1.75"x10g (44mm x 3.2mm) for both internal and external.

33mm definatly would not be large enough OD.

48mm x 3.2mm would be ideal for an external cage, but obviously design and quality of the bends plays a huge part in the roll cage strength...


RB
ORA

it depends if you ever want to use it in comp or not!
if you do then as rob said 43 od 3.2 wall is the min for a sub 1000 kg

but if your not planing on competing then you can use 33mm but you would need more of it, ie double hoop where you would normaly have one (one hoop inside the other) braced togeter and it would probably be stronger.
muliple small tubes (structured properly) will allways be stronger than a single tube, thats a basic engineering principle. but the strength comes with the structuring thats why the comp scrutes shy away from them (space frames) as it makes things more complicated..

if your not having to comply with any rules then build it how you like ! as even 20mm tube (if welded and structured properly) will add strength to the basic shell.. it will bend but it will take some of the stress from the shell.

ive seen a rops systems meet safety regs in industry that where made monoque form fabricated sheet! but it mainly boils down to if you want a "if" or "when" type cage

ok, i would like it to be in spec, would it still be in spec if i was to weld it myself?

iv bent up to 40 mm tube 3mm wall with a hydraulic bender, would the bender be ok for 48mm tube?

i dont see many jimny in comps, would a full external roll cage be to heavy for the engine?