Re: THe NAC Lots-O-Post Thread
Not for a go-cart
Its still a cage, which gets used far more frequent than yours will ever be. (unless you decidet to roll it at speed every time out)
Whatever, I called it the a-pillar. Didn't think anything of it.
Oh, trust us, we know you didn't think about it
yeah but you added those.
I'm still not sure I'd call the roof -to- wheel well supports "C-pillars" but I can see why people would call them that... and you're probably right since they technically kindof are c-pillars...
Ya, and you're adding a C-pillar too...
Its definitely not an "a-pillar".
Looks like Chris did all the hard work for me in point out how wrong Colin was.
See attached. I did one of those too...and it's actually a shit-ton more work because you have to document the entire thing, and you know how I am about measuring and drawing up plans etc...
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X2. Documenting everything sucks.
Our car got rolled over 5 times in one event, and no structural failure happened. There are 4 events 1 day, with two tries at each, then a 4 hour long head to head endurance race the 2nd day. Now there are 3 races per seaon, and all the time we go out and test and
purposely roll the car over.
So tell me Colin, is that a trivial thing when it sees that much abuse?
So it's more work because you have to write stuff down?
I figured a vehicle is more work because you have (want) to follow existing body lines.
I've been using nothing but a paint pen, angle finder, and my eyes :laugh:
Following body lines is a lot easier than starting from a blank canvas and making something that looks good and performs well.
For the MB stuff you have to do your entire design in FEA, justifying every tube, showing stress in various locations to simulate rollover protection, while minimizing weight & cost. And put all this in a presentation that you have to give before a panel of SAE judges.
Then you have to build it exact to your plans (yes, they check key dimensions on paper vs. the actual car) before you're allowed to race it. So it's a bit more involved than just 'writing stuff down'.
If you have existing body lines to follow, it's brainless work. Just bend it til it looks right, and forget about whether your design is optimizing pounds & pennies. Of course...then you have to go before a panel of internet arm-chair fabrication geniuses. Pick your poison I guess.
Damn that sucks, that does sound like a ton of upfront work.
Although if I had existing measurements and angles, that seems a lot less physical work to me.
Maybe I just suck at bending tube though. I sometimes have to do one bend 2 times or more just so I get the bend to match the body just right. If I knew what angle to go with from the start, it would go a lot quicker.
Knowing the angles sometimes is a pain, because you have to make it to those specifications. You can't just bend up a tube like you did, then make up more tubes to "fit" into where that one is located. If you bend a tube a couple degrees off on the Baja car, then you have to remake it.
Also, see below what Chris says about equipment
Knowing the exact angle isn't really all that useful with the equipment we have. If your bender is anything like mine, there's a gray area between when it starts grabbing the tube vs. when it actually starts bending as all the slop in the bolts & pins is taken up. Even if you find that point and start your angle finder at zero right then, you've still got springback, which can change depending on how big your angle is. Then it's all for naught if you're gonna guess at the rotation for multi-plane bends anyway.
Did you make one of these yet?
Far more valuable for matching body lines etc. than a true angle measurement...just hold it next to your tube while bending, and you can compensate for springback etc. before you actually take it out of the bender and lose your start spot.
I like winging it.
And that is why I should never ask for your advice on technical things.
Going from a standing 3' diameter locust tree to a stacked & split cord (~16" pieces) ain't exactly a lazy day.
