FIA Cage

[Matt]

Has anyone here built one that was actually legal? Trying to find out material that you used.

[Baron Von Crowder]

Ive never looked into FIA rules. I had the cage built in the fairmont to meet Lemons, Chump and SCCA/NASA rules. We built the main structure in 1.75/.095 DOM, and the door bars etc in 1.5/.120 DOM.

[Matt]

This is all it really tells you as far as material goes in the rule book

[Baron Von Crowder]

Looks to me that 1.75"/0.095wall DOM would be cool, or 2"/.083wall. Our rule book states similar, but has restrictions on 1.5", must be under 3k lbs race weight.

[Matt]

That is what I thought until I read this:

Actually you can't use DOM to build a true FIA approved cage since it is a welded mechanical tube with the internal weld seam removed. It's then drawn over a mandrel to produce a more uniform tube.
Cold Drawn Seamless (CDS) is a billet cylinder of steel that is heated up, then a bar is driven down the middle to create the seamless tube. The tube is then drawn over a mandrel (simlar to DOM) but it lacks the welded seam.
What is the size of your main hoop? FIA requires a 1.75 x 0.095 tube there at least. It's a bit of a document to read if you're truly building an FIA spec cage you really need to read it through.

[Mach1]

That is what I thought until I read this:

shiiitttt, that sucks! sounds big $$$

[Matt]

Looks to me that 1.75"/0.095wall DOM would be cool, or 2"/.083wall. Our rule book states similar, but has restrictions on 1.5", must be under 3k lbs race weight.

Where did you get your material from? Do you remember the price?

[Baron Von Crowder]

Where did you get your material from? Do you remember the price?

Ill be honest, I didnt have to pay a dime on this build. The past 3 cars we built I could have told you to the nickel what the material cost was, but that has been several years ago, and Im sure the prices are completely different. We used some DOM and some HREW, this one was the first completely DOM cage Ive had.

And now that I read whe you posted above, I remember that DOM is essentially HREW that has been Drawn Over Mandrel. Id hate to see that bill...

[Matt]

Last time I checked for DOM it was about $8 a foot. I didn't search very far. I can get chromoly for half of that. Wish FIA would alloy 4130!

[Baron Von Crowder]

what are you doing that requires an FIA cage?

[Matt]

Nothing ATM, Just trying to research.

[aggie97]

Last time I checked for DOM it was about $8 a foot. I didn't search very far. I can get chromoly for half of that. Wish FIA would alloy 4130!

Recently bought 1.75 x 0.095" for $3.75/ft got a smoking deal. Usually $4.25 to $5.00.

Also pretty sure you will never be racing in a class that requires FIA rules unless you are a true baller!