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Discussion Starter #1
Okay. I know I must be overlooking something blatant, and am about to get flamed. And no, I am not building one. :flipoff2:

But how come you can run a triangulated 4 link with just the uppers or just the lowers triangulated, but not a 3 link? In the triangulated 4 link, only the two triangulated links hold the axle laterally. It seems like it should work to make a 3 link in the same fashion? Just sitting here thinking.
 

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Discussion Starter #3
youre joking, ive seen your rig. either somebody else built it and your a rich dumbass, or youre joking:flipoff2:
I built it. Thanks for the complement. :D

But, I still don't see why you could not run a 3 link with triangulated lowers and a straight upper or vice versa. I must be missing something.
 

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are you talking about what would essentially be a 4 link with one link missing?

Or a "3 link" with the triangulated links converging to one joint? aka wishbone


theoretically a standard 4 link would still function with one link missing, but it would be almost entirely dependant on the one angled link to center the axle and control torque. not good.

MAYBE if you ran 2 straight uppers, and one angled super heavy duty lower from the center of the axle tube it would work. I'm sure the forces applied to the chassis when accelerating and braking would be a bit screwy.

If you ran 2 triangluated links and one straight link, you'd need to offset the one straight link far to the side.
 

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so... you are talking about a single triangulated 4 link with either one of the triangulated links or one of the straight links missing?

well, with straight lowers, your upper would have to be at a 45 degree angle to get 45 degrees total triangulation. In that case, the upper would be locating the axle laterally as well as preventing it from rotating. Thats a lot to ask of one link.


If you had triangulated lowers and a straight upper it would have to be way outboard otherwise your triangle while 45 degrees, would be very small with a huge amount of leverage on the opposite side of the upper link.
 

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Discussion Starter #6
are you talking about what would essentially be a 4 link with one link missing?

Or a "3 link" with the triangulated links converging to one joint? aka wishbone


theoretically a standard 4 link would still function with one link missing, but it would be almost entirely dependant on the one angled link to center the axle and control torque. not good.

MAYBE if you ran 2 straight uppers, and one angled super heavy duty lower from the center of the axle tube it would work. I'm sure the forces applied to the chassis when accelerating and braking would be a bit screwy.

If you ran 2 triangluated links and one straight link, you'd need to offset the one straight link far to the side.
Kinda. I am more thinking of a triangulated 4 link but with only, lets say, the lowers triangulated, and then removing an upper link. I understand that there would only be two links holding the axle side to side. But it works that way all the time.
 

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Discussion Starter #7
so... you are talking about a single triangulated 4 link with either one of the triangulated links or one of the straight links missing?

well, with straight lowers, your upper would have to be at a 45 degree angle to get 45 degrees total triangulation. In that case, the upper would be locating the axle laterally as well as preventing it from rotating. Thats a lot to ask of one link.


If you had triangulated lowers and a straight upper it would have to be way outboard otherwise your triangle while 45 degrees, would be very small with a huge amount of leverage on the opposite side of the upper link.
Not really what I was thinking. I was thinking triangulated lowerS with a straight upper. Forces on the upper would be no different than a regular three link. Forces on the two lowers would be no different than a 4 link with only two triangulated links, in my mind at least. :laughing:
 

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I'd want to run the lowers triangulated from the outside of the axle to the center of the chassis, and one upper as far out on the axle as possible.

Probably why people dont do this is tire clearance.
 

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I'd want to run the lowers triangulated from the outside of the axle to the center of the chassis, and one upper as far out on the axle as possible.

Probably why people dont do this is tire clearance.
yeah but imagine the leverage potential on the side of the axle without the upper link. If you hit a rock with any force it would rip the whole thing apart. Your fulcrum would be at the crossmember where the lowers converge... i think.
 

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Discussion Starter #10
I'd want to run the lowers triangulated from the outside of the axle to the center of the chassis, and one upper as far out on the axle as possible.

Probably why people dont do this is tire clearance.
Well, if I were ever to try it, I would place the two lowers way out on the axle and triangulated towards the center of the frame. Steering would not be an issue that way. Then I would run the upper in the center. I just don't see why it wouldn't work.
 

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Well, if I were ever to try it, I would place the two lowers way out on the axle and triangulated towards the center of the frame. Steering would not be an issue that way. Then I would run the upper in the center. I just don't see why it wouldn't work.
What?! then you have zero triangulation. I just mocked up the triangulated lowers w/ outboard upper on my scale model and it doesn't work. The axle housing rotates and allows the axle to move laterally.

pictures in a few minutes.
 

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What?! then you have zero triangulation. I just mocked up the triangulated lowers w/ outboard upper on my scale model and it doesn't work. The axle housing rotates and allows the axle to move laterally.

pictures in a few minutes.
i take that back.. you have triangulation, but an unbelievable amount of leverage on your link mounts.

My link ends aren't set up for triangulation so they are maxed out and I'm not getting acurate results on my mode. Might have to bust out the 4-link RC crawler and take a link off.
 

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there's no way a setup with 3 links with a total of 6 link joints will locate the axle laterally when any force or torque is provided
i say it can be done, but your links and mounts would have to be fucking strong.......none of that rover shit

how does a 1 link work???

Serg
 

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Discussion Starter #15
i say it can be done, but your links and mounts would have to be fucking strong.......none of that rover shit

how does a 1 link work???

Serg
:laughing:

A rover rear is a triangulated upper and straight lowers from the factory.

But yes, it would have to be strong.
 

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Discussion Starter #16
there's no way a setup with 3 links with a total of 6 link joints will locate the axle laterally when any force or torque is provided
Why? If a 4 link with only two triangulated works, removing one of the straight links is putting no more lateral force on the other three as it is not locating the axle in that plain. Now it immediately puts more force on the other upper link to locate the axle vertically, but we all know 3 links work. Again, where am I wrong. I know I have to be. :flipoff2:
 

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key points would have to be:

vertical seperation at axle end
included angle of A frame or triangulated arms
joints used
mount design
suck it and see
 

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maybe in something that doesn't see any kinda side loads, but this is rock crawling. With the setup you're talking about you'd need a RIDICULOUSLY HUGE crossmember to attach to, and even then I see things failing if you ever take a decent side hit, like say rolling and landing on the side of the tire, or hitting a rock with the outside tire in a turn at speed.

On our competition cars we run triangulated 4 links in the back, and on hard rolls it's not unusual to bend an upper link, or rip out tabs. We used to replace uppers on the RockHer1 fairly regularly because of this, and it had 2 huge beefy lowers, not just one.

Technically it'll work, but structurally it's far from ideal.
 

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maybe in something that doesn't see any kinda side loads, but this is rock crawling. With the setup you're talking about you'd need a RIDICULOUSLY HUGE crossmember to attach to, and even then I see things failing if you ever take a decent side hit, like say rolling and landing on the side of the tire, or hitting a rock with the outside tire in a turn at speed.

On our competition cars we run triangulated 4 links in the back, and on hard rolls it's not unusual to bend an upper link, or rip out tabs. We used to replace uppers on the RockHer1 fairly regularly because of this, and it had 2 huge beefy lowers, not just one.

Technically it'll work, but structurally it's far from ideal.
Well put.

/thread
 

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Why? If a 4 link with only two triangulated works, removing one of the straight links is putting no more lateral force on the other three as it is not locating the axle in that plain. Now it immediately puts more force on the other upper link to locate the axle vertically, but we all know 3 links work. Again, where am I wrong. I know I have to be.
Uh yes 3 links work. with a Panard bar to take the lateral forces. Campbells have twisted a couple 9" housings in 3 link set up. Thats with the upper doing only power control duty. I can't imagine how much force it takes to twist the housing especially after Shannon has trussed it. I doubt VERY highly that it would survive the additional forces of being the lateral locater as well. You trying to save weight? Be John Nelson? What?
 
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