Custom SE30 roll cage

#1

Merry Xmas everyone! We’ve been lurking the forums for some time now and would like to use our first post to showcase a project that one of our customers requested recently. This is our first SE30 build, but hopefully won’t be the last as we aim to support the South Eastern Spec E30 community. Have a look, leave some opinions/thoughts and don’t hesitate to contact us with any questions or requests.

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Crucial Motorsports Group, LLC
1520 State Ave
Unit C
Holly Hill, FL 32117
904-652-9732
www.crucialmotorsports.com
http://www.facebook.com/pages/Crucial-Motorsports-Group/79638420955

#2

The craftsmanship looks very good. I’m not crazy about the design and I am not sure the main hoop diagonal meets 15.6.7

#3

Thank you, we do tig weld all of our cages and try to display craftsmanship comparable to the top fabricator’s. The top of our main diagonal is within 12" of the corner meeting 15.6.7, the last few Grand Am cages that our fabricator has completed have pushed this rule limit slightly with the idea being to more evenly support the main hoop in a roll over. For us its a matter of also protecting our driver coaches and passengers in the same scenario. Do you mind being more specific on what your not crazy about?

#4

I’d like to see a picture of the Tig torch that reaches between the roof and top bars.

#5

Damn, nearly not a straight bar in that cage too! Straight bar is a stronger than the bent/curved one.

And with regards to the diagonal, the reason you have the diagonal meet in the corner is for exact you reason you want it to - strength in both pull and push. Bars are allowed not be in the exact corner, as having the bars meet together in the one spot is harder to fabricate. In your case the design of that diagonal really just works effectively in a push/compression situation, but does a lot less to spread its load through the other bars, than if it was closer to the corner. Think of it this way, if you try and distort a solid triangle shape, you will only succeed if you distort all three bars, as the joints spread the load.

Have a look at a few fully engineered cages, and you’ll notice none will use a design like yours.

I think the quality of the cage looks great, but the design is flawed by the excessive bends and compromised diagonal.

#6

Aussie_racer has it right. Also, I am not sure the diagonal meets the rule on the bottom end. Need diagonal for roof bar, not straight, door bars could be done with 2 bends instead of 4 and accomplish the same effect. I also like bars from the bottom of the main hoop to the rear down tubes mounting point.

#7

Thank you for the criticism and suggestions guys. See ya’ll at the track in 2012.

#8

The following was pirated from the 2011.8 CCR regarding the bottom end of the hoop diagonal. Note the bolding.

[quote]15.6.7 Diagonal Brace
One (1) diagonal brace shall be used in the same plane as the main hoop. The diagonal
should be one continuous path; meaning that it must conform to Diagrams 15.6.7a or
15.6.7b. Note- If the installation method from Diagram 15.6.7b is used, the builder
should pay close attention to alignment. One end of the diagonal brace shall attach to
the corner, or horizontal part, of the main hoop above the driver’s head, within twelve
(12) inches of the driver’s-side corner. The other end of the diagonal brace shall attach
to the mounting plate (or to the main hoop as close to the mounting plate as practically
possible) diagonally opposed to the driver’s head (passenger floor).[/quote]
With that being said, the connection of the bottom end of the hoop diagonal looks to be several inches north of the main hoop mounting plate, while it would not have been impossible to lower it.

I cannot recommend reading this thread enough: “Cage Design” on Corner-Carvers.com

Mark