cause the judges don't like (rod ends in bending)

[exFSAE]

Cars with rod ends in bending and/or single shear mounts definitely have kicked major ass back in the day...

...so did F1 cars with treaded dry weather tires.

[Jon @ Electromotive, Inc.]

That picture is from an A-Mod autocrosser posted up for sale in the early days of the forum. The link referenced a later post by the guy selling the car (at least I think it was the guy selling the car).

[Owen Thomas]

OK, so I went to the website and saw the whole vehicle from that photo... needless to say my assumptions about design goals were wrong. That thing is (was?) a nightmare on wheels.

The point still stands that if you have a team with low technical knowledge and need a car in 2 months, using heavy REIB may not be such a bad idea.

[Z]

Originally posted by Tim.Wright:
I'm not a fan of these sweeping statements such as rod ends in bending are unacceptable ...
...
... the other taboo, single shear, can be easily justified for packaging, tolerance and assembly reasons. After having "single shear is evil" drilled into my head for years, I sat down and actually thought about it myself and came to the conclusion that it can be ok.

I suggest you do the same on this subject. Think about it yourself instead of relying on a sweeping statement which has no context.

Tim,

Awww, now you're making me feel all awkward... I AGREE with everything above! (Geez, I might have to retract earlier comments. )
~~~~~o0o~~~~~

Getting back to the OP's proposed wishbone design, I see very little wrong with it (wider base at each end would be better). The main problem here is the almost religous devotion of some people to a particular design approach.

The GT40 designers, and countless others like them, got their quick-and-dirty, camber-adjustable, REIB-and-single-shear, wishbones designed early, and then went on to solve all the other problems required to win. If they had to fiddle around with countless shim-adjustable, double-shear, clevis-mounted, staked-in-BJs, then they may well have ended up with cars very similiar to many FSAEers. Namely, late-finished (so untested), over-weight, over-priced, over-complicated contraptions that even with very liberal aero rules, and after ~25 years of polishing, can not consistently corner at more than 2G.

And these FSAE cars have the expensive wishbones acting as "the fuse", rather than having cheaper and more easily replaced bolts, or rod-ends, acting as the weak links. Many Design Judges either turn a blind eye to FSAE cars shedding wheels via failed wishbones, or else they actually encourage this. So why the aversion to a design (REIB) that can do the same thing, but in a cheaper and perhaps more controlled way?
~~~~~o0o~~~~~

I should also point out that many of the best ever designers whose work I have seen have almost everything in "single-shear". Perhaps the foremost example of this is Nature, who clearly loves mounting things in single-shear (and with lots of bending!). Look at trees (trunk-to-ground, +++, leaves-to-twigs) and skeletons (bone-to-bone) for good examples of what actually works.

Z

[MCoach]

Well, the overall car looks a lot better than expected.

It's an A-mod car. It's cool to see some things outside FSAE.

[eilonoz]

i still see a lot of difference between my example and the others that were discussed here.
at most of the examples the bending stress came from the sphere bearing which is the primary force acting on the rod end.
i was talking about taking a prety minor force that i have to transform to the chassis somehow.
i dont want to save money or do anything accept of doing it in the best way (weight\strength).
still wouldn't it be the best?

heres a remoinser where we began
https://docs.google.com/docume...16_fQmHVfWceXjm0/pub

[M. Nader]

That's why the judges don't like them. just saw this and thought i'd post here

[atm92484]

Except none of those rod-ends are in bending...

It wouldn't surprise me if there was more to the story than the picture is telling.

[Tim.Wright]

rod end as a bumpstop for the motherflippin win!

[M. Nader]

Originally posted by atm92484:
Except none of those rod-ends are in bending...

It wouldn't surprise me if there was more to the story than the picture is telling.

Massive banking put things in an awkward geometry, bending the rod ends. that's what the owner confirmed with me.

How can you tell from the picture they weren't in bending? maybe you can make a case for the lower one where i would guess too little thread was attached, but the rocker one i had no doubt it carried bending load.