Post awesome AI car shit:First time Ive seen a Golf with a hole in one like that

The Something Awful Forums > Discussion > Automotive Insanity > Post awesome AI car shit:First time Ive seen a Golf with a hole in one like that

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Octopus Magic: Dec 19, 2003; I HATE EVERYTHING THAT YOU LIKE* AND I NEED TO BE SURE YOU ALL KNOW THAT EVERY TIME I POST

*unless it's a DSM in which case we cool ^_^

Dome S101 from 2001

# ? Jan 19, 2013 18:19

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# ? May 14, 2024 17:53

Poing: Jul 25, 2001; Gaze into my eyes...

Are those dampers rotating on single-shear pivots?

# ? Jan 19, 2013 18:40

MrKatharsis: Nov 29, 2003; feel the bern

Collateral Damage posted:

Solar Coaster posted:

I scrolled past this a bit too quickly at first and didn't realize what it was. That is awesome. Where do I buy one?

The only place I've ever seen them in the wild is Seattle, and they're not jacked up or modded at all.

http://seattle.craigslist.org/see/cto/3511117094.html

# ? Jan 19, 2013 18:45

mobby_6kl: Aug 9, 2009; by Fluffdaddy

Palpatine MD posted:

Don't be modest, there are also hints of incestuous liaisons with a Testarossa and an SLS.

Let's not overcomplicate this, it's basically a baby RS200 with gullwing doors:

huge

And I'd buy like 10 of them if they were available in Europe

# ? Jan 19, 2013 21:47

Giblet Plus!: Sep 14, 2004

Poing posted:

Are those dampers rotating on single-shear pivots?

Yes and it looks like it works just great so there's no need to obsess over it. Do you obsess over single sheer ever time you step outside and see a tree?

# ? Jan 19, 2013 22:22

Slavvy: Dec 11, 2012

Giblet Plus! posted:

Yes and it looks like it works just great so there's no need to obsess over it. Do you obsess over single sheer ever time you step outside and see a tree?

I don't really understand what's going on here, can someone explain single shear anything to me?

# ? Jan 19, 2013 22:24

angryhampster: Oct 21, 2005

Slavvy posted:

I don't really understand what's going on here, can someone explain single shear anything to me?

1 single bolt serving as a pivot point on the dampers. This results in lots of shear (lateral) force put on it a single possible failure point, rather than spreading the force out over several to reduce the opportunity for failure and lessen stress on the bolts.

# ? Jan 19, 2013 22:30

Slavvy: Dec 11, 2012

How would you spread the force out to several bolts? Doesn't it ultimately have to pivot on some sort of shaft+bearing anyway? I don't see the big deal really, if you just make the bolt/shaft/whatever thick enough it'd work fine wouldn't it?

# ? Jan 20, 2013 00:09

Party Alarm: May 10, 2012

http://upload.wikimedia.org/wikipedia/commons/b/b7/Bolt-in-shear.PNG

Click that.

# ? Jan 20, 2013 00:24

Slavvy: Dec 11, 2012

So you would have some sort of plate that the top of the bolt goes through, which is bolted to the chassis?

edit: \/\/\/\/\/ seen.

Slavvy fucked around with this message at 00:33 on Jan 20, 2013

# ? Jan 20, 2013 00:28

EightBit: Jan 7, 2006; I spent money on this line of text just to make the "Stupid Newbie" go away.

Rather than have the pivot point bolt into a flat surface, it would be better to have the pivot point in a big C, like this:

code:

Bad:


         ||
         ||
         ||
�������������������

Better:

   ____
  |   ||
  |   ||
  |   ||
���������������

The difference is that the top diagram not only has shear forces, the bolt is also a cantilever. The bottom bolt won't be able to flex as much and can handle much higher loads given the same materials.

# ? Jan 20, 2013 00:30

jammyozzy: Dec 7, 2006; Is that a challenge?

This is all well and good, but if you look reallllll close at the rockers you'll see the dampers are in double shear anyway.

No (sane) engineer would put a bolt that important into single shear, that's like babytown frolicks.

jammyozzy fucked around with this message at 00:35 on Jan 20, 2013

# ? Jan 20, 2013 00:32

Poing: Jul 25, 2001; Gaze into my eyes...

Not seeing a second mount point for the cantilevers. :can:

What's up with the N-arms anyway?

# ? Jan 20, 2013 07:16

jamal: Apr 15, 2003; I'll set the building on fire

Those rockers aren't just bolted down; there's a big boss sticking out of the transmission case that they pivot on. The bolt is just keeping it in place and not under any shear loading.

And the upper arm is n-shaped to provide toe adjustment and ensure there isn't any bump steer (like there would be if the toe link was not in the plane of one of the a-arms).

# ? Jan 20, 2013 07:20

Giblet Plus!: Sep 14, 2004

jammyozzy posted:

This is all well and good, but if you look reallllll close at the rockers you'll see the dampers are in double shear anyway.

No (sane) engineer would put a bolt that important into single shear, that's like babytown frolicks.

Look here, it's the palatov dp4. Look at all that single sheer. But we all know that palatov guy's rich and does whatever he wants:

And everyone's favorite, the C7 cervette. What were they thinking those steering links and ball joints are gonna just fly apart the moment it steps onto pavement. GM junk I guess.

And look at this moron, trusting his life to a single sheer fork. Serves him right for trying to be a unique snowflake when physics is involved:

And the god engineer must be smoking white pebbles, because this poo poo is in single sheer as well. I mean really, why doesn't the trunk connect to ground twice. Sloppy design if you ask me.

# ? Jan 20, 2013 18:03

FuzzKill: Apr 1, 2005; Snuff the punk.

Giblet Plus! posted:

And the god engineer must be smoking white pebbles, because this poo poo is in single sheer as well. I mean really, why doesn't the trunk connect to ground twice. Sloppy design if you ask me.

Banyan trees are clearly superior in design :colbert:

# ? Jan 20, 2013 18:09

Bob NewSCART: Feb 1, 2012; Outstanding afternoon. "I've often said there's nothing better for the inside of a man than the outside of a horse."

If anyone watched the barrett Jackson auction last night, there were two pretty awesome AI sales.

The original bat mobile for 4.2 million, and the first production C7 for 1,050,000

# ? Jan 20, 2013 18:09

NoWake: Dec 28, 2008; College Slice

Those are all examples of well-engineered single shear connections, the bolts and connections are clearly beefy enough to withstand the dynamic forces they'll see, and then some. I'm betting most of the guys getting all up tight here remember that terrible SEMA truck from a few years back, each corner was supported by two 1/2" bolts in single shear and it went to poo poo from bouncing off a dirt mound the size of a parking block.

story here

# ? Jan 20, 2013 18:24

rcman50166: Mar 23, 2010; by XyloJW

I took an engineering class specifically designed to teach shear, bending and torque. It's pretty easy to design for and single point shear is considered ethical engineering design if proper analysis has been done. Also as long at the mount isn't threaded. That is considered poor engineering regardless of how high the safety factor is.

# ? Jan 20, 2013 18:45

jammyozzy: Dec 7, 2006; Is that a challenge?

Alright maybe I was a bit over-dramatic and should have said no engineer would do that without good cause and justification.

As penance, pictures:

# ? Jan 20, 2013 19:05

Sir Cornelius: Oct 30, 2011

rcman50166 posted:

I took an engineering class specifically designed to teach shear, bending and torque. It's pretty easy to design for and single point shear is considered ethical engineering design if proper analysis has been done. Also as long at the mount isn't threaded. That is considered poor engineering regardless of how high the safety factor is.

I graduated as a Master of Mechanical Engineering in 1990. Unless something has severely changed since then, you're perfectly right.

# ? Jan 20, 2013 20:17

Rev. Dr. Moses P. Lester: Oct 3, 2000

rcman50166 posted:

I took an engineering class specifically designed to teach shear, bending and torque. It's pretty easy to design for and single point shear is considered ethical engineering design if proper analysis has been done. Also as long at the mount isn't threaded. That is considered poor engineering regardless of how high the safety factor is.

What do you mean exactly, "as long as the mount isn't threaded"?

# ? Jan 20, 2013 21:00

Skeletard: Dec 21, 2004

I assume that he means that the point where contact is made isn't threaded, considering surface area and all that?

# ? Jan 20, 2013 21:38

jamal: Apr 15, 2003; I'll set the building on fire

A friend's corolla:

# ? Jan 20, 2013 21:40

red19fire: May 26, 2010

This seems like an old VHS video so I'd imagine it's been posted before. Guy drifts two BMW's at once (presumably with a steering/throttle lock).

https://www.youtube.com/watch?v=GE1VTWFDEFg

# ? Jan 20, 2013 23:05

Crustashio: Jul 27, 2000; ruh roh

Skeletard posted:

I assume that he means that the point where contact is made isn't threaded, considering surface area and all that?

You just design for the reduced area, I've seen a lot of perfectly safe designs that use single shear bolted connections. Rear shocks on my car mount to the hub in single shear with one bolt and they will punch through the upper mount before they shear that bolt. I've seen a lot of shoulder bolt connections in manufacturing that have lasted for a very long time. Ideal design is a double shear, straight pin connector but in the real world engineering requires many compromises because of space or ease of assembly.

Crustashio fucked around with this message at 00:04 on Jan 21, 2013

# ? Jan 20, 2013 23:22

b0nes: Sep 11, 2001

Sagebrush posted:

Hey, at least she's not like my friend's cousin, who told us all at dinner once, in no uncertain terms, that if her would-be-fianc� didn't get her a diamond worth at least three months' salary she would leave him on the spot. That would be around twenty thousand dollars for the poor guy (not in attendance that night) she was dating at the time. Because anything less than that would show that he didn't respect her, you see.

(Unless $4k IS three months' salary for you, in which case, I truly admire your commitment to this girl)

So he left her right? Cause ultimatums are not good ways to start marriages.

(USER WAS PUT ON PROBATION FOR THIS POST)

# ? Jan 20, 2013 23:48

rcman50166: Mar 23, 2010; by XyloJW

Rev. Dr. Moses P. Lester posted:

What do you mean exactly, "as long as the mount isn't threaded"?

As long as the cantilever that experiences the shear force isn't threaded it is ok. An easy way to fix this is to simply use a shouldered bolt.

Crustashio posted:

You just design for the reduced area, I've seen a lot of perfectly safe designs that use single shear bolted connections. Rear shocks on my car mount to the hub in single shear with one bolt and they will punch through the upper mount before they shear that bolt. I've seen a lot of shoulder bolt connections in manufacturing that have lasted for a very long time. Ideal design is a double shear, straight pin connector but in the real world engineering requires many compromises because of space or ease of assembly.

That is the problem. You don't design for the reduced area. Stress risers experienced during shear make it more vulnerable to failure than a rod of the same diameter as the minor diameter of the bolt thread. That assumption is one of the reasons it's a no no. You may have seen plenty of designs but it's not considered ethical engineering because a better solution exists with minimal design change.

rcman50166 fucked around with this message at 00:50 on Jan 21, 2013

# ? Jan 21, 2013 00:45

Left Ventricle: Feb 24, 2006; Right aorta

jamal posted:

A friend's corolla:

Come on man, you know better than that. Just throwing a picture like that into the thread and leaving? We gotta have a link.

# ? Jan 21, 2013 00:46

kastein: Aug 31, 2011; Moderator at http://www.ridgelineownersclub.com/forums/and soon to be mod of AI. MAKE AI GREAT AGAIN. Motronic for VP.

I see single shear in mounts all the time - for instance shock mounts are frequently single shear.

EightBit's example of how to make something double shear is really not a good idea though, because if you connect the mount tabs on each side of the bolt together with a plate that's parallel to the bolt, you've barely increased the strength at all. You need triangulation / a gusset that shares load equally between the two mount tabs to make a truly effective double shear mount point.

# ? Jan 21, 2013 00:59

rcman50166: Mar 23, 2010; by XyloJW

kastein posted:

I see single shear in mounts all the time - for instance shock mounts are frequently single shear.

EightBit's example of how to make something double shear is really not a good idea though, because if you connect the mount tabs on each side of the bolt together with a plate that's parallel to the bolt, you've barely increased the strength at all. You need triangulation / a gusset that shares load equally between the two mount tabs to make a truly effective double shear mount point.

The point I'm making is single shear design is okay. Single shear (or any shear for that matter) on a full length threaded bolt or any bolt where shear takes place on the threaded section of it is not okay. Examples of that is seen everywhere including older F1 cars. But it's still poor engineering and unethical if designed deliberately despite knowing the problems caused by it.

# ? Jan 21, 2013 01:05