I am currently building my cage with all straight bars, no bends. It takes a little planning. I feel a bent tube is more likely to bend in a rollover than a straight one. I am welding all horizontal bars, dash, behind seat, top of window driectly to the cab, and notching all other to fit these. I'll try to get some pics in a few days.
Look at others cages, both racers and play cars and get the opinions of builders, shops ect. before actually driving ang having to use it.
Art with MDR tech will gladly look over your truck if you bring it to a race.
I think bent tubes are the way to go as long as the welds are good.
I just rolled my truck a few weeks ago and I have bent tubes that make up my cage. I was goin about 70 and rolled it over twice and it held up great so i think it depends what type of metal you use and how good your welds will hold.
certain outside corners in your construction should be continuous bars. your right straight bars are stronger, but bends may bend, they won't crack. all bends should be trianglated with another bar from the inside of the bend to reinforce it.
my new race truck has only about 12 bends in the entire truck, but using straight bars in those areas would have been foolish. so the answer to your question is that both are required to make a strong cage. if you want to see a step by step cage buildup check here: www.rosshoek.com
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