Yeh i will be going to a couple shops to source out some DOM piping. and just use the bar i have now as a guide so i can have the shop make the bends. So i guess its just a mock up[/QUOTE]

Remember its tube not pipe there is a difference! and they will sell you what you ask for. But good call on going with DOM, HERW is half the price but not quite as strong, if you go with the HERW make sure you use a thicker than required wall.

 

 

Seriously? Results? We're over here trying to SAVE HIS LIFE and he's calling us dumb and bitching about calling him out on his stupidity. Still.

Results:

hey guize luk at dis i'm gonna kill myself with dumb idea

Hey, you shouldn't do that.

shut up cuz ur dum i h8 u

Really, that's a bad idea.

k i'll change it but ur still dumb

...

Gratitude much?

 

how is "******* idiots from illinois" any form of advice. its ironic because it says he is from illinois

 

the only real advice i am getting from here is to make the main hoop out of one continous dom tube. where's the other 4 pages of this are going....nowhere

 

If you think the only advice you've been given is to use DOM tubing, you've just made my point.

 

Advice here was to make the main loop out of dom tubing, the other 4 pages are there to tell you that its a waste of your time for a product that wont be well appretiated. There really isnt a point in wasting your time to make something that is already on the market for a reasonable price. You're spending money and an amount of time that would be worth more than $400 for a weaker product that isnt even tested. We're also saying its better to know that if your life could be saved at the expense of a rollbar, it would have to be a reliable one that would get the job done. I mean cmon, you're gonna spend money making a mockup, then spend more money making the real one? Seriously? Just for cosmetics? Why not just buy one that looks good and most definitely works. I know you want triangles everywhere on your rollbar to give it that hardcore look and thats why you're doing it. Most of us have been on that "wanting it to look good" path. Just get a harddog DD. You can add a cage to it if you want.

 

ok.. so why does every one get a hard on for dom? what about hrew and crew? i saw this forum on there where they even used sprinkler piping for a 4x4 roll cage and it held up to 3 rolls so far. :S not so sure about sprinkler piping.

 

Because I get a "hard on" for knowing that I'll stay alive. It's very arousing.

Also: Miatas usually crash at much higher speeds than 4x4s, and you only have one hoop, not a whole cage to distribute the load.

E=.5(mv)^2

If you don't know what that means, you have no place designing safety equipment. If you do know what that means, you wouldn't build that "roll bar."

At this point, go ahead. You know better than every racing organization in the world. Make it out of sprinkler piping. Then test it at 100mph.

 

im just more of a diy type of guy. I mean i spent much much more on my turbo build, and peicing it all together, than just buying a kit from begi. I mean look at my signature.

 

Why are you preventing natural selection? Tree-hugger.

 

You can be a DIY guy and do things right. If you don't know what you're doing, admit it. Research it. Look into it. Learn. Be humble when you do things wrong. When you're wrong and you argue and insult those who attempt to help you, that's just rude, as well as counterproductive to your learning.

 

How much do you think you will be saving by building this yourself? Proper material is one part of the equation, actually knowing how to weld is another. What are you using for a welder? Can it properly penetrate the material you are welding. Obviously from your questions you don't know anything about about building a roll bar. You know what, neither do I. I bought mine and called it a day. I'm all about saving a buck, but honestly this isn't where you should be looking to save pennies.

Seriously, this is one area not to DIY.

 

there is a way to be helpful and not be so offensive about it also

 

I can understand that. Im the same way. Custom keeps a car unique, but this isnt one of those things you completely do on your own unless you've done a ton of em. I think you should start with an already tested bar and then expand on it. Thats how to get the best looking and functional ones. I remember someone made their own full cage out of a harddog about a year ago. It looked amazing and I wouldnt doubt that its better than the full spec miata cages. We're just lookin out for you in the most fowled mouth way.

 

are HREW and CREW cold worked after their made? that's the difference. DOM = drawn over mandrel as I said before. Essentially a tubular set of rollers that cold work the metal into a stronger piece.

 

Custom Roll Bar Build - ClubRoadster.net - the link on page three is what i want to do... with the exception that it will go all the way down behind the seats.

 

right hrew and crew, im sure could be neglected. I saw it on a 4x4 site where they discussed roll cages. I then realized that they dont go as fast as we do when they roll. f=ma so lets just say our cars weighs about 2000 lbs 2000 lbs x 100 mph = force of 200000 lbs mph so does this mean to get the same force out of a 5000 lb 4x4 they would have to travel 40 mph and roll right?... just comparing apples to oranges. nothing useful

 

Are we not helping you the way you want? Are you not getting strangers time and effort exactly how you want it? Free advice isn't enough for you, those people choosing to help you be safe, to not die should really be really nice to you as well.

Do you complain about your welfare check not being big enough too?

EDIT: As to your figures above... I'm dumbfounded. I put the equation in my post and you still didn't use it. A car moving at a steady rate of 100mph in F=MA has no force (in a frictionless environment). Mass x Acceleration. Acceleration =! Steady speed. You want the equation I ALREADY PUT UP. KE=1/2MV^2. Second, what offroaders weigh 5000lbs? Purpose built jeeps/toyota trucks/FJ cruisers/ect weigh closer to 2k/3k. Maybe 4. And 40mph is a little high for offroading in a situation where you might roll over, but whatever. .5(3,000 lbs x 40mph)^2 = 160,461 ft/lbs of force. Certainly more than enough to ruin your day. Now a Miata. .5(2,300 lbs x 100mph)^2 = 768,874 ft/lbs of force. Almost six times as much force, except now we're putting it into a little Miata instead of an SUV, and into one little hoop for protection instead of a cage. These forces are not to be underestimated.

 

This thread has been crapped all to hell you guys. ls1 has recognized the flaws in his original design and is going to redo it the way I pointed out in the clubroadster thread. Lets just let it go...