SES Bracing Inquiry

[BontragerEric]

Hi my name is Eric Bontrager.

I have been preparing to submit the SES and have noticed a few discrepancies with the model our team has created. Within the SES, on the Front Hoop Bracing sheet it calls out 1 tube; 1" OD and 0.065" wall (25.4mm OD 1.6mm wall). My question is, is that 1 tube component determined from the side profile of the frame and does that bracing support have to connect to the baseline of the frame?

I have attached what our frame currently consists of and would prefer a little more confirmation before we started to make final changes. My worry is that I did not take into consideration the correct size tube for bracing the front hoop. This is my first year as an FSAE member and have learned a lot, but if I missed any key details within the rules I would appreciate any advice from a more experienced member. Thank you all.

976

Best Regards,

Eric Bontrager

[Mitchell]

This rule is fairly poorly written but from what I can see your frame is fine.

There is no good clarification of "front hoop bracing" vs "front bulkhead support structure". I submitted a rule clarification a year or so ago and confirmed that the minimum required structure between the front bulkhead and front hoop is 3 members - an upper consisting of 1.6mm wall, a lower of 1.25mm wall and a triangulation member of 1.25mm wall. Now obviously this would leave your side impact structure/front hoop node unsupported so is unrealistic but it is handy to know.

I should also add that your lower member could be 1.25 and your upper (behind the front hoop) could be whatever thickness you like.

Hope this helps.

[Ahmad Rezq]

To confirm what Mitchell said. I've also submitted a RULE ISSUE TICKET TO FSG and this was the response. I was asking about the Front Zone Minimum Members number and Minimum Tube Size. The response also included the highest member above the side impact which is mentioned in Mitchell Comment.
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[Adam Farabaugh]

This rule is fairly poorly written but from what I can see your frame is fine.

There is no good clarification of "front hoop bracing" vs "front bulkhead support structure". I submitted a rule clarification a year or so ago and confirmed that the minimum required structure between the front bulkhead and front hoop is 3 members - an upper consisting of 1.6mm wall, a lower of 1.25mm wall and a triangulation member of 1.25mm wall. Now obviously this would leave your side impact structure/front hoop node unsupported so is unrealistic but it is handy to know.

I should also add that your lower member could be 1.25 and your upper (behind the front hoop) could be whatever thickness you like.

Hope this helps.

The difference between "front hoop bracing" and "front bulkhead support" is that "front bulkhead support" must be 1.25mm wall, 3 members back to the front hoop. "Front hoop bracing" on the other hand is only 1 member and must be 1.6mm wall, and should extend to the bulkhead, but doesn't necessarily have to.

So as I understand the OP's frame is fine. But see the two members going forward from top of the front hoop? They could make the uppermost one .049 and the one just below it 0.065 and be fine as well.

Anyway OP, your frame looks fine in this view op and is a fairly standard way of solving the FSAE problem.

[BontragerEric]

Thank you all for the quick and concise explanations. I can sleep a little easier at night. Good luck to all competing and have a great weekend.

Regards,

Eric Bontrager

[Mitchell]

The difference between "front hoop bracing" and "front bulkhead support" is that "front bulkhead support" must be 1.25mm wall, 3 members back to the front hoop. "Front hoop bracing" on the other hand is only 1 member and must be 1.6mm wall, and should extend to the bulkhead, but doesn't necessarily have to.

You're correct. I was pointing out that the front hoop bracing tube can be one of the three front bulkhead support tubes. The rules read as if 4 tubes are required - to me at least.