Topic: Box Tubing Roll cage

Hey, thanks for checking this out. I was wondering whether we could make a roll cage out of square tubing. This avoids the need for an expensive pipe bender as I could just cut bend and weld. None of the specifications seem to directly prohibit it, but all I've read specify tube diameters and wall thicknesses. Thanks, everyone.

Re: Box Tubing Roll cage

EFF NO!!!

Today is not Aprils Fools is it?

1990 RX7 "Mazdarita"  1964 Sunbeam Imp (IOE 2013 Sears Pointless) 2002 Jaguar x-type (Winner C-Class 2021 Sears Pointless)
Gone bye-bye
1994 Jaguar XJ12 (Winner C-Class 2013 Sears Pointless)  1980 Rover SD1 (I Got Screwed 2014 Return of Lemonites)

Re: Box Tubing Roll cage

That was a bit harsh.  Check out https://rollcagecomponents.com/ and buy from them.  Have someone competent notch and weld it for you.  This isn't an area to scrimp on.

1990 RX7 "Mazdarita"  1964 Sunbeam Imp (IOE 2013 Sears Pointless) 2002 Jaguar x-type (Winner C-Class 2021 Sears Pointless)
Gone bye-bye
1994 Jaguar XJ12 (Winner C-Class 2013 Sears Pointless)  1980 Rover SD1 (I Got Screwed 2014 Return of Lemonites)

Re: Box Tubing Roll cage

cheseroo wrote:

EFF NO!!!

Today is not Aprils Fools is it?

I see that's unfortunate. I was hoping to save money haha.

Re: Box Tubing Roll cage

cheseroo wrote:

That was a bit harsh.  Check out https://rollcagecomponents.com/ and buy from them.  Have someone competent notch and weld it for you.  This isn't an area to scrimp on.

Thanks.

Re: Box Tubing Roll cage

schiffinor wrote:

Hey, thanks for checking this out. I was wondering whether we could make a roll cage out of square tubing. This avoids the need for an expensive pipe bender as I could just cut bend and weld. None of the specifications seem to directly prohibit it, but all I've read specify tube diameters and wall thicknesses. Thanks, everyone.

it's been covered but if you look at the "How NOT to fail tech" guide, every single picture is round tubing. A square tube cage would fail catastrophically at the main hoop since you couldn't make it a single continuous piece.

1992 Saturn SL2 (retired) - Elmo's Revenge -  Class B winner, Heroic Fix winner x2
1969 Rover P6B 3500S(sold) - Super G-Rover - I.O.E Winner, Class C Winner
1996 Saturn SW2 - Elmo's Revenge (reborn!), Saturn SL1  Dazzleshipm Class C x2 and IOE winner
1974 AMC Javelin - Oscar's Trash heap - IOE,”Organizer's Choice" and "I got Screwed" award winner

7 (edited by Spank 2021-05-06 05:16 PM)

Re: Box Tubing Roll cage

This is very helpful Lots of pictures

https://24hoursoflemons.com/wp-content/ … 040419.pdf


BTW: If you post where you are, you may get offers of help. For example, I have a tubing bender and would be happy to help you bend your cage tubing.I'm in SoCal

Re: Box Tubing Roll cage

Safety is the wrong place to pinch pennies. A roll cage is your first line of defense in any major accident, roll over or not. Square tube simply is not as strong, period. Cages made from tons of pieces welded together where the bends should be are not as strong and will not pass in just about any racing series. I'll be dammed but you're right the rules don't use the word "round", but they do say "Properly bent, racecar-grade and -quality tubing is mandatory".

Lemons puts itself out there as the "joke" racing series, but it's still dangerous. You can still get severely hurt. Ignoring safety makes it more likely that you will get hurt. And hearing that a driver got sent away in an ambulance is just about the worst thing any of us can hear on race day. Pay the money for a good cage. Pay the money for real racing brakes. Pay the money for good harnesses that are easy to tighten. Pay the money for good fire gear. You can buy and prep the actual car for cheap, but your safety gear should be decent. I'm not saying you have to bankrupt yourself to be safe, there are ways to keep costs in check. Find people like Spank who are willing to help you build the cage and you'll save some fabricator costs. Look for the sites selling lightly used suits from NASCAR and similar. Ask around on where people have found good deals on fire suppression systems. But take it all seriously.


One example from a few years back. Team was using old cheap street brake fluid, and boiled their brakes coming down the straight at Thompson. One of the scarier crashes I've seen. Their cage worked. They could have avoided it entirely by using a real racing brake fluid (seriously, ATE type 200 is great stuff and cheap).
https://www.youtube.com/watch?v=4rRqRKC0nG8

20+ Time Loser FutilityMotorsport
Abandoned E36 Build
2008 Saab 9-5Aero Wagon
Retired - 1989 Dodge Daytona Shelby 2011-2015 "Lifetime Award for Lack of Achievement" IOE, 3X I got screwed, Organizer's Choice

9 (edited by Lemon_Newton-Metre 2021-05-07 08:57 AM)

Re: Box Tubing Roll cage

tl;dr: ROUND.

Supporting argument:

Here's the pertinent text:

"3.E.1.a Rollbar Tubing and Spreader-Plate Specs. Minimum tubing size for cars weighing under 3000 pounds as raced is 1.50″ x .120″ or 1.75″ x .095″. Cars weighing over 3000 pounds as raced must use a minimum tubing size of 1.75″ x.120″. Properly bent, racecar-grade and -quality tubing is mandatory: no stretched or crushed bends allowed."

First, let's assume an understanding that as different vehicles have different dimensions, there no need to specify a length of tubing for any particular structural member.

Second, I agree with TheEngineer there's no "round"; but also no instance of the word "diameter" above.

And, OP did use "diameter" in his post.

But it does say "tubing", and there are two dimensions.

Reducto ad absurdum:
OP _could_ have made an inquiry about using flat stock for a cage, since there were only two dimensions;
for example: 1.75″ x.120″ - or: 1 3/4" wide, by about 1/8" thick.

... with the exception of the word, "tubing".

"Tubing" implies a hole - pretty much by definition.

"Diameter" relates to something circular.

All the square stock "for sale" listings I've seen discuss width x height x wall thickness, and then, length (which we're disregarding for this discussion).

Without a _third_ dimension specified, the "tubing size" specified actually _implies_ a diameter; again, by definition.

And since square stock at any size varies from a 'diameter' (and it's especially obvious at 1.5" or "1.75"), I'm going to contend the rules actually specify round tubing by definition and implication. Q.E.D.

Re: Box Tubing Roll cage

While I agree, it is not uncommon to discuss square (not rectangle) tubing with only 2 dimensions. 1"x.120 is how most people communicate 1" square tubing with a wall of 0.12". When you get to rectangle, or non-square box, you add another dimension.

So I see how one could wiggle themselves into the idea that "the rules do not exclude square tubing". But you have to really wiggle that argument and be willingly ignorant of the fact that every racing series uses round tube for cages. Which, yes I can see someone with zero racing background honestly having never seen a cage before and not knowing, but if you're that new, it might be wise to just pay someone who knows about these things.

20+ Time Loser FutilityMotorsport
Abandoned E36 Build
2008 Saab 9-5Aero Wagon
Retired - 1989 Dodge Daytona Shelby 2011-2015 "Lifetime Award for Lack of Achievement" IOE, 3X I got screwed, Organizer's Choice

Re: Box Tubing Roll cage

Understood; and agreed, it's not uncommon for people to be imprecise.

Ryerson, getmetals, alro, metalsdepot, techsteel.net, industrialtube - again, every listing I saw on the infallible internet had two dimensions for _only_ round tubing; and again: the length, of course.

That's why I went through the supporting argument.

I don't have your experience with those discussions; however, this explains my neverending confusion when someone asks me to bring him a "two by", with more than one size in the pile.

Re: Box Tubing Roll cage

TheEngineer wrote:

...every racing series uses round tube for cages.

I see someone has never been to the grain truck races in Lind, WA.

https://www.lindwa.com/Grain%20Truck%20Rules.html

"...minimum 2"x2" square tubing pieces..."

In the interest of full disclosure, I admit I went there to see the combine demolition derby, not the races, but it turns out that grain truck races are awesome.

1982 MG Metro 1300: IOE 2015 Pacific Northworst GP, Longest Distance 2010 Cd'L Box Wine Country Classic
1980 KV Mini 1: Worst of Show and Fright Pig Supremo 2009 Concours d'Lemons
1978 H Special: Second-Round Elimination 2010 Lemons Pinewood Derby at Sears Pointless
1967 SAAB 96: IOE 2012 Pacific Northworst GP, Organizer's Choice 2022 Hell on Wheels California Rally

Re: Box Tubing Roll cage

mharrell wrote:
TheEngineer wrote:

...every racing series uses round tube for cages.

I see someone has never been to the grain truck races in Lind, WA.

https://www.lindwa.com/Grain%20Truck%20Rules.html

"...minimum 2"x2" square tubing pieces..."

In the interest of full disclosure, I admit I went there to see the combine demolition derby, not the races, but it turns out that grain truck races are awesome.


I tip my hat to your ability to find something to the contrary. Well done.

20+ Time Loser FutilityMotorsport
Abandoned E36 Build
2008 Saab 9-5Aero Wagon
Retired - 1989 Dodge Daytona Shelby 2011-2015 "Lifetime Award for Lack of Achievement" IOE, 3X I got screwed, Organizer's Choice

Re: Box Tubing Roll cage

Ok, but I don't think that counts, because:

1. there's no minimum wall thickness indicated ;-), and
2. that isn't a series, it's just a one-off event - more an exhibition than a race, anyway.

(... I'm just gonna stop right here, now)

Re: Box Tubing Roll cage

mharrell wrote:
TheEngineer wrote:

...every racing series uses round tube for cages.

I see someone has never been to the grain truck races in Lind, WA.

https://www.lindwa.com/Grain%20Truck%20Rules.html

"...minimum 2"x2" square tubing pieces..."

In the interest of full disclosure, I admit I went there to see the combine demolition derby, not the races, but it turns out that grain truck races are awesome.

My guess is that they don't reach triple digit speeds.

Capt. Delinquent Racing
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The One & Only Taurus V8 SHO #31(now moved on to another OG Delinquent)
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Re: Box Tubing Roll cage

I was really looking forward to seeing Schiffinor bend box tube without kinking, and some square tube fish-mouths! I admire the spirit of saving money by using something you are familiar with. That is one of the best parts of this series.  Good luck when you do get to the track!

Re: Box Tubing Roll cage

Lemon_Newton-Metre wrote:

that isn't a series, it's just a one-off event - more an exhibition than a race, anyway.

They run throughout the day, between combine demolition derby heats, year after year. Heck, first prize is $300 against an entry fee of $10, which is a significantly better potential ROI than certain other series I could name...

DelinquentRacer wrote:

My guess is that they don't reach triple digit speeds.

Well, after a decade of Lemons in ten different cars at six tracks, neither have I.

1982 MG Metro 1300: IOE 2015 Pacific Northworst GP, Longest Distance 2010 Cd'L Box Wine Country Classic
1980 KV Mini 1: Worst of Show and Fright Pig Supremo 2009 Concours d'Lemons
1978 H Special: Second-Round Elimination 2010 Lemons Pinewood Derby at Sears Pointless
1967 SAAB 96: IOE 2012 Pacific Northworst GP, Organizer's Choice 2022 Hell on Wheels California Rally

Re: Box Tubing Roll cage

mharrell wrote:
Lemon_Newton-Metre wrote:

that isn't a series, it's just a one-off event - more an exhibition than a race, anyway.

They run throughout the day, between combine demolition derby heats, year after year. Heck, first prize is $300 against an entry fee of $10, which is a significantly better potential ROI than certain other series I could name...

Series!

But only in Lind, WA. You're equating the intermission entertainment at one annual, single-day, agriculture-focused event in a presumably rural area in the PNW, to a multiple location, multi-state, cosmopolitan series.

But - I see what you did there.

mharrell wrote:
DelinquentRacer wrote:

My guess is that they don't reach triple digit speeds.

Well, after a decade of Lemons in ten different cars at six tracks, neither have I.

(is this Lemons bragging?)

Re: Box Tubing Roll cage

mharrell wrote:
DelinquentRacer wrote:

My guess is that they don't reach triple digit speeds.

Well, after a decade of Lemons in ten different cars at six tracks, neither have I.

Clearly you need a different speedometer gear.

Capt. Delinquent Racing
RUST-TITE XR4Ti - '21 ARSE-FREEZE-APALOOZA  I Got Screwed
The One & Only Taurus V8 SHO #31(now moved on to another OG Delinquent)
'17 Vodden the Hell - (No) Hope for the Future Award, '08 AMP Survivor, '08 ARSE-FREEZE-APALOOZA Mega-Cheater

Re: Box Tubing Roll cage

DelinquentRacer wrote:

Clearly you need a different speedometer gear.

I suppose as far as that goes, units weren't specified.

Lemon_Newton-Metre wrote:

(is this Lemons bragging?)

Well... yes.

1982 MG Metro 1300: IOE 2015 Pacific Northworst GP, Longest Distance 2010 Cd'L Box Wine Country Classic
1980 KV Mini 1: Worst of Show and Fright Pig Supremo 2009 Concours d'Lemons
1978 H Special: Second-Round Elimination 2010 Lemons Pinewood Derby at Sears Pointless
1967 SAAB 96: IOE 2012 Pacific Northworst GP, Organizer's Choice 2022 Hell on Wheels California Rally

Re: Box Tubing Roll cage

mharrel - lol, nicely done.