Tube size for Buggys and exos

[Gunmetal_45]

Hi guys,

I ran a search and couldnt find something specific on this.

I'm looking to buy some new dies for tube bending.

first building an exo and bars etc.. then possibly a buggy

and am wondering what size/grade/wall thickness tube people use

and does anyone know how well a 1.75" die will bend 1.669" OD tube?

and in 4130 tube what wall thickness will surfice if i go down that track?
0.120" .095" .083" or can i get away with even thinner for weight saving?

Cheers!

[Slunnie]

Not really sure, but I though that most used 32mm nominal bore.

[Gunmetal_45]

32 nominal bore is 42.2 or 42.4 OD, depending on manufacturer, which is why i was wondering if a 1.75" die will also bend 1.669" (42.4mm) tube as well as 1.75" a i can get quite decent pricing on 4130 in that size.

Also in 1.75" (1 3/4") whould a 6" or 7" CLR die be more flexible in application?

[Slunnie]

I wish you better luck than what I had re CLR.

[Gunmetal_45]

I wish you better luck than what I had re CLR.

what die did you hade problems with? and what CLR and what dramas did you have?

[HIGH ROLLER]

Most people iam aware of use 1 3/4 for there buggies some also use 1 1/2 which is hat ia built mine from 3.2mm wall, all my bending was with a jd3 1 1/2(38mm) die my understanding is if the tube is too small for the die you will end up with deformed bends.
There are tube benders measured in the tubes od and pipe benders measured in the nominal bore size, if you go too thin in wall thickness you may also end up with deformed bends i was told best not to go less than a medium grade in wall thickness.
The tube i used was erw rt3832 from horan steel in Newcastle.
Hope this helps you

[Gunmetal_45]

I figure 1 3/4 was going to be the most common size, just i cant find a supplier of imperial mild steel tubing that is reasonably priced (DOM pref or ERW) though it would be handy in cold rolled too for sliders as there ont as criticle.

Also i figure shock hoops and the like would generally be smaller diameter, 1 1/4? 1 1/2?

Im in Melb if anyone knows an imperial tube size supplier it would be appreciated.

[Slunnie]

I wish you better luck than what I had re CLR.

what die did you hade problems with? and what CLR and what dramas did you have?

No probs, I was only trying to find out what CLR people were using. No reponses so I just assumed they didn't know.

[Gunmetal_45]

I wish you better luck than what I had re CLR.

what die did you hade problems with? and what CLR and what dramas did you have?

No probs, I was only trying to find out what CLR people were using. No reponses so I just assumed they didn't know.

Yeh with the cost of Dies, i cant justify differnt CLR's as for a lot of things the larger will make a nicer looking buggy, but the smaller may be better to keep closer to panels etc.. or make sliders.

it would be good to see some stuff and know what CLR dies were used.

[bru21]

The thinner wall the tube the bigger CLR you need.

Exo's are ver weak in design and need massive tube. Mine was braced well (for an exo) and it still flexed - it was 2"

My buggy is 13/4" and 11/2" 4130. .120 majors, .095 itermediates and thinner for bracing.

The tighter the CLR the stronger the cage willl be from a flex point of view.

That said Drag cars use massive CLR's as they use thin wall tubes.

[Gunmetal_45]

.

That said Drag cars use massive CLR's as they use thin wall tubes.

drag cars generraly use 1.625" (1 5/8") tube with .083 wall in 4130.
at least the ones i know of, but im unsure of the CLR of the dies used.
and of the extra strench from a larger CLR.

thats why i was wondering if the thinner wall in cro-mo would be as good as the thicker mild.

[bru21]

for general 4x4 use heavier wall tighter clr

there are rock related crush issues to worry about, and a greater wall thickness will add only 12kg to a cage - which as a % is nothing on a 4x4.

[Gunmetal_45]

For exos and bars, do most use 32 nominal bore cold rolled steel? (ie: cheap stuff)

and internal cages seamless? or cro-mo?

[bru21]

No one really uses seamless (in aus anyway)

DOM / dom 4130 is nearly seamless anyway.

DOM is generally much higher MPA then mild steel - some test results have been in the 600MPA compared to 280 odd for pipe.

DOM isn't a hell of a lot dearer really. 4130 is my buggy is up to about 5k of the stuff!

I would use 38mm od tube rather than 32NB as the die can then be used for dom / 4130 and its the same price in mild as pipe is.

[Gunmetal_45]

I cant find a good DOM supplier, what cost does the one you use charge for 1.75" DOM 3.2 wall?

as i can get 1.75" (.095 wall) 4130 for $130 a 6m length

[Weiner]

I cant find a good DOM supplier, what cost does the one you use charge for 1.75" DOM 3.2 wall?

as i can get 1.75" (.095 wall) 4130 for $130 a 6m length

Give these guys a call, they are in Braeside

http://www.rollcages.com.au/

[steve patrol]

In keeping to this topic... what are the specs for a comp spec exo cage? Or are there any?
Ie does it have to be 4130 CrMo or can it be your standard seamed tube?

[steve patrol]

In keeping to this topic... what are the specs for a comp spec exo cage? Or are there any?
Ie does it have to be 4130 CrMo or can it be your standard seamed tube?

[bru21]

No comp recommends 4130 - some allow it. You can't mig it (well some guys do with massive exp, and get away with it) but its not ideal - TIG is the go. It is not as good as mild steeel for multiple rolls - except where braced / designed very well - as a combination of the lower wall thickness and poorer weld make it unpredictable. V8 super cars use about 30 different sections for 1 cage, I have seen them first hand and spoke to the engineers. That the level of design i'm talking about. The cages generally evolve over years of crash testing too.

Heaps of guys are using it on challenge trucks and the welds can and DO fail - i've seen some failed welds on almost every truck with 4130.

$130 for that 4130 @1.74 is cheap as - who's it from.

I buy mine from performance metals.

There are no exo specs I know of - just make it safe.

4130 doesn't save much weight as tube is not available in infinate wall thicknesses - so most use the same as they would in mild. bending creates more issues as the tube kinks if the clr is not big enough.

cheers bru