minimum rollcage tube size

[lcwizard]

I've probably built 500 cages, mostly for land cruisers. I have never had a failure with the HREW tubing. I have literally made thousands, perfhaps tens of thousands of bends with that tubing from 1" to 2" diameters and never seen a tube split no matter the location of the seam. I have, however seen DOM fail during bending. The reason is the DOM proces work hardens the material making it less elastic. Most people are unaware that it is available in a "normalized" condition, or stress relieved. I have seen 1 1/2 DOM tear on the outside radius during bending. CroMo is also prone to this. If you use either DOM or CroMo be sure to specify "normalized" tubing. Most yards only bring in standard DOM so they will probably need to order it.
Oh and by the way I usually stick to 2" .120 wall for a truck as heavy as a cruiser. It's not worth the wieght savings to go undersize. A basic cage would use less than 60 feet of tube . An elaborate cage, seatcradles, dash bars, gussets all over, would exceed 100 feet. 100 feet 2" 120 is about 240 lb, 100 feet
1 3/4 is about 210, and 1 1/2 about 180lb

[Medusa]

I was shooting for 2" x.25 chromoly. Yeah I know $$$ so hope 2"x.25 DOM will be sufficient.

I am curious...how do you plan on bending 2" x .250 tube (forget chromoly, even mild steel)?????

A lot of the discussion above has focused on the HREW vs DOM debate. IMO more consideration ought to be give to wall thickness and strength vs weight tradeoffs. For a chassis I think the best combination is 1.5" with a 0.156 wall. I think a cage or roll bar in 1.750 x 0.156 would also work well. For parts that take a real beating (e.g., sliders) I have been using 1.75 DOM with a 0.188 wall. It has, however, been difficult finding shops able and/or willing to bend that thick of tube. LT and Tydes are the only two friends I still have after that kind of bending request

[4rnr]

Originally Posted by lcwizard

I've probably built 500 cages, mostly for land cruisers. I have never had a failure with the HREW tubing. I have literally made thousands, perfhaps tens of thousands of bends with that tubing from 1" to 2" diameters and never seen a tube split no matter the location of the seam. I have, however seen DOM fail during bending. The reason is the DOM proces work hardens the material making it less elastic. Most people are unaware that it is available in a "normalized" condition, or stress relieved. I have seen 1 1/2 DOM tear on the outside radius during bending. CroMo is also prone to this. If you use either DOM or CroMo be sure to specify "normalized" tubing. Most yards only bring in standard DOM so they will probably need to order it.
Oh and by the way I usually stick to 2" .120 wall for a truck as heavy as a cruiser. It's not worth the wieght savings to go undersize. A basic cage would use less than 60 feet of tube . An elaborate cage, seatcradles, dash bars, gussets all over, would exceed 100 feet. 100 feet 2" 120 is about 240 lb, 100 feet
1 3/4 is about 210, and 1 1/2 about 180lb

So are you claiming that HREW is in someway superior to DOM or Cromo??

[lcwizard]

no, just a better all around material. It does have a lower tensile strength but it doesn't work harden like moly so it will go far longer without cracking. A moly chassis should be replaced in three or four seasons less if it's run a lot. The material work hardens with vibration and cracks. I see a lot of people weld moly with standard steel wire so the weld points offer no advantage. To handle moly correctly tig or pulsed mig is the only way to go. Along with the proper wire and gas. Then to get the true advantage moly offers the whole part needs to be annealed or the areas near the weld are brittle.
DOM is a goog choice for a guy with Mig capabilities as long as you specify
"normalized" DOM when you order. Factor in the cost the the gain is little if the HREW does the job well.
I've built cages from simple offroad to full race quarter mile cars and seen them roll dozens of times, never any failures

Originally Posted by 4rnr

So are you claiming that HREW is in someway superior to DOM or Cromo??

[PKP80]

Originally Posted by Medusa

I am curious...how do you plan on bending 2" x .250 tube (forget chromoly, even mild steel)?????

Brute Muscle strength...I've been hitting the gym real hard and eating all my veggies, lol.

Hydraulically via some fancy overpriced bender. I'm learning about bending, a friend is instructing me on the how to.

[awp_cruiser]

muddogbob,

I am in Seattle. Where did you get tube from?

Thanks!

[Medusa]

Hydraulically via some fancy overpriced bender

Please let us know when you identify this bender.

[Mace]

Originally Posted by Medusa

Please let us know when you identify this bender.

Jack, I have used a JD Squared manual bender with a long ass bar to bend both 1.5" .25 wall and 2" .25 wall. Both bends were ~45*, the bender did NOT like it but it did work.. The biggest thing with the manual benders is making the stand sturdy enough.. These benders can bend the tubing, but honestly over time they will break. They are not rated for that kind of abuse.

[Isotel]

Redline's Bender is up to the task , but 2" .25 wall Chromo is just Silly.. Bigger is not always better.

[awp_cruiser]

This will be longish - and I hope not to much of a hi-jack but related -

So I am ready to start my cage building project. I've read a lot of threads here and on Pirate. There seems to be no end to the discussion or debate. The most frustrating thing is the slang vs the techincal.

Based on what I've read I've decided to build my cage with the following:

1.75x.120 DOM for the main structure.
1.75x.095 HREW for infill, diagonals, spreaders, etc.

So I go to get a price and source the material. I call the large and very reputable source in Seattle. They don't carry DOM but they can get it. They refer me to their supplier and tell me to pick what I want and let them know and they'd price and order it for me.

Earle M. Jorgensen Company ® - Products - Stock List

Now... DOM or Seamless? 1010 or 1020? Or is it A513? Normalized is which? I am not looking for a chemical brakdown of these materials, but what is it I am looking for again?!!

Then HREW... 1010 is the stuff I am looking for?

Specifically, in techincal terms, does anyone have a suggestion as to what material I should order?

Let's discuss the tube, thickness, and design later.


Thanks!

[LandC1973]

FYI - Because of the link below (and others) and computer modeling I went with 2" standard schedule 40 pipe for my cage because of price, welding considerations, and I not racing fast on dirt tracks.

tube strength vs schedule pipe

Is schedule 40 pipe strong enough? [Archive] - CK5 Forums

pipe sizes

Lighting Pipe Sizes

[muddogbob]

Originally Posted by PKP80

Brute Muscle strength...I've been hitting the gym real hard and eating all my veggies, lol.

Hydraulically via some fancy overpriced bender. I'm learning about bending, a friend is instructing me on the how to.

Metal supermarkets in Woodinville
metal supermarkets loc: Woodinville, WA - Google Maps

[Taz]

2" .120 Dom will hold up just fine in a violent 80 roll (multiple) as long as the cage is built right. I beleive Nascar only allows Dom to be used because chromo is too brittle?

[PKP80]

Originally Posted by Taz

2" .120 Dom will hold up just fine in a violent 80 roll (multiple) as long as the cage is built right. I beleive Nascar only allows Dom to be used because chromo is too brittle?

Mark was that the size for the Baja80 you boys built?

[Taz]

yes it was...as required by SCORE ... It saved a few lives

[cruzerman350]

i built my whole cage out of 1 7/8" schedule 40 i believe, i rolled it and it didnt budge. you just have to put gussets in the right places and keep as many bars straight as you can. i only have 4 bends on my entire cage. also if you use an exhaust bender it makes a stronger tighter bend. thats what i was told and it worked for me.

[Mace]

please don't use an exhaust bender......

[lowtideride]

It depends I think on how big of a dick you are to people.

If your a big dick= sch 40 PVC

Not a dick= DOM/HREW


So to decide what you should make your cage out of, you must first find out how big of a dick you are

[bustanutley]

A cage is not something to cheep out on...

[Isotel]

Originally Posted by awp_cruiser

Now... DOM or Seamless? 1010 or 1020? Or is it A513? Normalized is which? I am not looking for a chemical brakdown of these materials, but what is it I am looking for again?!!

Have you read this article on Pirate??
Pirate4x4.com - The largest off roading website in the world.
Its mostly about Suspension Links but has some good info on differences in steel , Somewhere there is an article on the bible of metal strength, but i cant find it now

Originally Posted by bustanutley

A cage is not something to cheep out on...

You mean i shouldn't build a cage out of Poop Pipe (Sch 40) with a Harbor Freight Kinker ?? Its just a Safety Item

[awp_cruiser]

Thanks Isotel.

I hadn't seent that article. That is exactly what I was looking for.

Muddogbob, I appreciate the lead. I'll give 'em a call.

Andy

[LandC1973]

lowtideride -- Wait…who the hel- said PVC (Polyvinyl chloride) pipe would work. Yes that is a really, really bad idea. I’m talking about Steel Sch 40 NOT PVC Sch 40.

PVC = Death

[lowtideride]

Originally Posted by LandC1973

lowtideride -- Wait…who the hel- said PVC (Polyvinyl chloride) pipe would work. Yes that is a really, really bad idea. I’m talking about Steel Sch 40 NOT PVC Sch 40.

PVC = Death

Yulp I Know what I said.

It was a joke.

[LandC1973]

On “Trucks” (the TV show on Spike TV) they actually got an old Bronco and someone used PVC to make the roll cage and painted it black. That’s why I didn’t know if you were joking or not, it’s happened before.

DOM and HREW are definitely stronger per the weight but Pipe is easyer to bend, weld, and cheaper per the strength… If you don’t care to much about the weight Sch 40 or 80 could be a good option.