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PostPosted: November 8, 2020, 4:19 pm 
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Yea I dont understand Bent Wrench?

Sure if it had poly bush's and tried to adjust the rear point it wouldnt work, with with the rod ends it would allow adjustment to the degree until the rod end bottomed out in either direction


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PostPosted: November 8, 2020, 5:26 pm 
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You have to adjust the rear point so the front bolt lines up. Then you are done, not much else you can do.

There is another version of those arms on the webz that has a pivot point where the rear leg meets the ball joint end, but those arms have no mid brace for the bent leg.

Speedworks tried to fix it by doing this,

Image

I don't know what the outcome was.

I also note on this pic that the sway bar mount is offset, from the centerline of the member it attaches too, and will impart a twisting force on the lower arm.
I would try and avoid that.

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PostPosted: November 8, 2020, 8:07 pm 
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Duh! I had a momentary brain fart. It wasn't until I drew it out in cad and measured angles, that I realized you are right. Sorry :mrgreen:

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PostPosted: November 9, 2020, 4:04 pm 
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Ditto, lol visualizing it was making my brain hurt (warning computing power low) Drew it in CAD, set the relative constraints and yes for it to move fore/aft the link bar also needs to extend/shrink and swivel


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PostPosted: November 9, 2020, 5:26 pm 
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Hermit wrote:
Ditto, lol visualizing it was making my brain hurt (warning computing power low) Drew it in CAD, set the relative constraints and yes for it to move fore/aft the link bar also needs to extend/shrink and swivel


That why I've been building mine with a clevis on the last few builds.

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PostPosted: November 9, 2020, 5:43 pm 
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The control arms that are shown in the first post are DOUBLE adjustable on close inspection. The rod ends are threaded into a threaded bushing(right/left threads). This allow for camber and caster adjustments without removing the chassis attach bolts. They are not designed to have a spring/shock attached to them. Probably for a MacPherson strut to allow adjustability.

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PostPosted: November 10, 2020, 4:58 pm 
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Hermit wrote:
Is there any reason you couldnt have the connections on the ball joint end both pivoting like it is on the right, instead of the left solid and right pivoting.
While you might be able to design a symmetric solution, having 3 joints on that end would under constrain the upper ball joint and let the spindle flop around like a wet noodle. There are other versions that bring the clevis mount around so that both links would come in at more of the same angle, although it will reduce coilover space somewhat.


Kartracer47 wrote:
The control arms that are shown in the first post are DOUBLE adjustable on close inspection. The rod ends are threaded into a threaded bushing(right/left threads). This allow for camber and caster adjustments without removing the chassis attach bolts.
The rod end positions may be adjustable, but any adjustment you make to just one of them will change the distance between the rod ends. The distance between the chassis mounts in this configuration is generally fixed. Without flexing the mounting brackets, there is a (limited) singular arc of combined caster/camber adjustment that can be made while maintaining the distance between the rod end centers. As noted, because of their position/angle relative to each other, it's almost all camber with very little caster change. Which is good, because more camber actually necessitates less caster in this configuration. However, there also appear to be unequal length spacers on either side of the rod end as well, potentially allowing a second option for distance between mounts. This would provide a binary adjustment shifted primarily for caster. Assuming the rear mount axis is correct as shown, which it often is, the unequal spacers would give small binary adjustment in anti-dive.

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PostPosted: November 10, 2020, 7:06 pm 
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Quote:
While you might be able to design a symmetric solution, having 3 joints on that end would under constrain the upper ball joint and let the spindle flop around like a wet noodle. There are other versions that bring the clevis mount around so that both links would come in at more of the same angle, although it will reduce coilover space somewhat.


This may be a case of my brain running out of compute power again (i really need an upgrade)

But with 2x rod ends (one to the left and one to the right of the ball joint) and the balljoint connected to the spindle I cant see how It can move?

Without the balljoint connected to the spindle it could move in a +/- camber direction but once its attached to the spindle which is attached to the lower arm that rules that movement out?

The arms cant get longer or shorter so no movement that way?

let me know what im missing


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PostPosted: November 10, 2020, 7:21 pm 
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Hermit wrote:
But with 2x rod ends (one to the left and one to the right of the ball joint) and the balljoint connected to the spindle I cant see how It can move?
You've basically just made your control arm a 4-bar mechanism:

Image

Point C is your ball joint. There is nothing substantially constraining the rotational motion at any of the joints shown, allowing C to flail around as various forces are imparted on it. But remove the excess degree of freedom by locking the rotation at point A or B, and it's not going anywhere.

The ball joint is your outboard 'rod end' for the locked side.

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PostPosted: November 10, 2020, 10:20 pm 
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Ahh yes I didnt take into account the "bars" being able to pivot on the body side also. As soon as I saw that pic I got it. Hmm I wonder how I can work on my mental imaging.

Gotcha :) Thanks


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PostPosted: February 14, 2021, 4:21 pm 
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Driven5 wrote:
Even more so than that I tend to gravitate towards this general design, either with or without the crossbar:
Image


Where do I get a crossbar like that?


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PostPosted: February 14, 2021, 5:44 pm 
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Speedway or any other roundy-round supplier.

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