Gusset Welding in Detroit 2006

[Steve Yao]

As posted by Mike Cook in the Competitions forum:
http://fsae.com/eve/forums/a/tpc/f/825607348/m/23910726331/p/11


To clarify on the seatbelt bar:

For our shoulder belts, a bar is welded between the roll hoop. HOwever this bar has small bends at both side which make it a few inches behind the plain of the roll hoop. The judges we're worried that the moment caused by this offset would twist the seatbelt bar and break the welds. Therefore they said we needed to guesset the bar. When asked, can we just do some calculations to show that the bar would bend before the moment would break the welds, and their reply was no.

Could other teams from the Detroit comp comment of this please? Specifically, was this the case for all teams that were asked to weld gussets i.e. an unsupported shoulder belt mount projected out behind the Main Roll Bar.

Our seat belt mounts are in the center of some well triangulated straight tubes. I don't believe the judges would have issue, but I've heard of and seen many re-interpretations of the rules at competition.

[Steve Yao]

As posted by Mike Cook in the Competitions forum:
http://fsae.com/eve/forums/a/tpc/f/825607348/m/23910726331/p/11

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">To clarify on the seatbelt bar:

For our shoulder belts, a bar is welded between the roll hoop. HOwever this bar has small bends at both side which make it a few inches behind the plain of the roll hoop. The judges we're worried that the moment caused by this offset would twist the seatbelt bar and break the welds. Therefore they said we needed to guesset the bar. When asked, can we just do some calculations to show that the bar would bend before the moment would break the welds, and their reply was no. </div></BLOCKQUOTE>

Could other teams from the Detroit comp comment of this please? Specifically, was this the case for all teams that were asked to weld gussets i.e. an unsupported shoulder belt mount projected out behind the Main Roll Bar.

Our seat belt mounts are in the center of some well triangulated straight tubes. I don't believe the judges would have issue, but I've heard of and seen many re-interpretations of the rules at competition.

[drivetrainUW-Platt]

We had a U shaped 0.75" dia bar running backwards from the main rollhoop probably 5", we were required to brace it with 2x2" triangular plates

[CMURacing - Prometheus]

we've always run 1/2in diameter bars from the shoulder bar down to the "ass" bar in our chassis. the shoulder bar is a few inches behind the plane of the main roll hoop, and these "seat" bars (which also locate the firewall, seat, etc.) are run to a bar which is midway between the roll hoops welded to the bottom side-impact bar. the judges were going to make us weld on a gusset, thankfully one of our sophomores made what he thought was a "too obvious" comment about our seat bars that made us ok.

[Steve Yao]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by drivetrainUW-Platt:
We had a U shaped 0.75" dia bar running backwards from the main rollhoop probably 5", we were required to brace it with 2x2" triangular plates </div></BLOCKQUOTE>

Mike,
Off topic, but it sounds like you passed tech with a harness support tube that was 0.75" dia. As I understand it from Section 3.3.3 we are required at have 1" X 0.065" tube for harness mountings. Any thinner tube would have to have a thicker wall, was this the case with your harness mounts?

[drivetrainUW-Platt]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by SEY:


Mike,
Off topic, but it sounds like you passed tech with a harness support tube that was 0.75" dia. As I understand it from Section 3.3.3 we are required at have 1" X 0.065" tube for harness mountings. Any thinner tube would have to have a thicker wall, was this the case with your harness mounts? </div></BLOCKQUOTE>

Sorry, it is 1" I was thinking of the head rest bars, I should know since I welded the caps on the end of the 1" bar....but that last week before competition is all a blur now...It appears some ppl are still talkin about this under the comp thread