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      01-26-2025, 03:23 AM   #3618
dogbone
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Quote:
Originally Posted by kolosy View Post
When you were building your cage, did the builder have an opinion on the nascar bar s bends being close to the center of the span of the bar? I asked for nascar bars and my guy wants to send them through the b pillar instead of around.
We never had a conversation about the structural integrity of the NASCAR bar bends. From a conceptual standpoint, part of the NASCAR bar structure's strength comes from the bars being connected by those three vertical pieces. This "webbing" makes the system stronger than just an individual bar. In a more hardcore build, they would have a third horizontal bar placed at the bottom of the door frame and welded to the frame along the bar. Then, you would connect all three with a bunch of vertical pieces. This would make the "web" quite a bit stronger. Something like this:


I'm not a structural engineer, but I don't know if I would want to punch large holes or cutouts in the B-pillar in multiple places for multiple tubes. The pillar just doesn't seem very wide to me to be potentially weakening it like that. But, if somehow that was deemed the best solution, I would very much want the main hoop somehow solidly tied-in to the B-pillar to reinforce it.

And, maybe I don't understand, but wouldn't going through the B-pillar interrupt the door structure and function? I think you may face some challenges with the doors.

If the bar bends are a concern, perhaps one could design a third horizontal bar at the base of the door, weld it to the cage and frame, and then put a bunch of vertical connections amongst all three bars. That would have to be strong as heck. But, I'll say it again----I'm not a structural engineer, so consult an expert.
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