Projects What do you guys think of this wishbone/ladder bar connection?

The concept is sound, but the engineering on that setup is severely lacking. Take a look at F6Garagerat's set up. He used one large Heim joint. What ever you do stay with the concept. Ladder bars and four links subject the chassis to constant twist. I have seen cases where the twist caused damage to the body sheet metal.

Just my 2¢ worth, keep the change.

 

I don't think so. Seems it would not have to pivot around the bolt because the heims in the main lower bar would have more than enough movement.
I was wondering why not just weld the mount to the crossmember but also wondering about needing to remove it or assemble it- maybe it needs to be bolted. I have no idea on reasoning why, just thoughts and guesses.

 

Those are 1.25 OD bars with 0.125 wall and chromemolly hardware.
I'm more than reasonably certain it's quite capable of standing any hotrod on the back bumper with enough engine up front to do it. It performs a different function than the ball and socket on a 85 hp car with a torque tube.

 

31V, from the link you provided:

The swivel is the key that makes this Twenty First Century ladder-bar work under your ride without binding during body and suspension movement.

Sounds like it might have a bushing in there. Otherwise why mount it with one bolt?

 

31 Vicky, it does look beefier when viewing the link to get a sense of scale. The first pic looked like something off a toy wagon.

Having said that, after looking at the pics in the link, it would appear that when the ladder bars and panhard bar swing in arcs, they would be pulling away from each other, especially given that the panhard is not parallel with the axle.

 

Maybe the bolt does pivot then?
This is why I posted this for discussion.

There's always a great discussion on torsional stresses thru axles and bones or ladder bars. I saw this and I said to my self, "self that's pretty neat- hey wait a minute ???"

 

I think this is too simple, nothing to "shock and awe" the knuckle draggers!

 

Well with a single heim and bones there's no triangulation adjustment.
With a Pete and jakes style bar you'd have some at the rear.
That's one advantage I see to having double heim joints.
It really is over kill for a daily driver, but there's some good ideas there, I think anyway.

The pinion angle adjustment is brilliant although a tad busy. There again only for guys who need to tweak it for wheels up launches. Most guys don't mind setting it up once or twice and drive it. If you need to dial it just right or change it for track conditions that would be the cats ass IMO.

I'd say its more for bumper planters and wheelie bar dragers than for knuckle draggers. But if I knew for sure I wouldn't be asking.

 

Not sure if those heims will have enough movement. Also what is with that center bolt setup? A bracket off the cross member for each heim turned 90 degrees off the ground would work better since there should only be up and down movement.

 

I wonder if a part like this would do the same job? [ or a single heim joint ]
But that wouldn't be hot-roddy enough while re-inventing the wheel to get the same results.

 

Not liking it. Too much stuff.

 

I'll jump into some discussion on it I guess!

1) The pinion "adjusters" could have been easily done with left and right threads and clevis' on either end of the tube for simplicity and cost.

2) I don't like the way the clevis tabs are welded right along the top of the threads that hold the Heim joints.
To me...it seems like additional stresses are being applied to that area in a way that could compromise the threaded joint below.

3) Under power or braking, the Heim pivot balls are being stressed in such a way that they want to be popped out of their outer housings. My feeling is that they should be radially stressed. I guess thats how it should be termed.

4) The widget the Heims go in. It's made in a form of double sheer. Am I seeing right in that the upper and lower sheer plates, the main strength of the design and a critical fabrication, are attached to the central block by just a single plug weld on top and I assume the same on bottom?
The heat pattern suggests it!

5) I think the holes for the Heim joints are too close to the edge of the sheer plates. I would like to see a little more meat, all things considered.

 

^ this is all you need. It's simple, it's Ford, it's cheap and easy, and it works. Anything else is pretty much a compromise. Why compromise?

 

Some of us think too much. How many have actually produced a rear end kit? I have not. I know what works, this one may work OK but is clunky like I said before. Too many times we try to get too cutesy with this shit. This application is for a Tri 5 Chevy...........when did the leaf springs become obsolete!?!?!?!

 

Modern ladder bars typically have similar pinion adjusters, just in the back. I agree, joining the bars at the front into one joint, be it a tie-rod end, ball joint or rubber bushing would be a lot simpler, if less fancy.

 

The center pivot is not necessary. The bones could be easily attached with independent brackets on the cross member. For a car that is rolled in and out of a trailer, its fine. For a car that is driven, its dangerous. That center pivot will show serious wear in under 500 miles, if it hasn't failed already.

 

I will add, the welds are very nice. Excellent attempt at a poor design.

 

3) Under power or braking, the Heim pivot balls are being stressed in such a way that they want to be popped out of their outer housings. My feeling is that they should be radially stressed. I guess thats how it should be termed.



^^^
That is what makes the biggest question mark in my thought process.
But I see turning the mount 90* gives a bolt clearance problem.

 

How much horsepower will that hold before it breaks?
Henry had the bones and a torque tube for 85 hp.

 

Actually that was on the front. The torque tube did all the work in the rear. It was big and beefy with a big ball/socket swivel point at the gearbox.

 

Around the time the economy went up and people had enough spare change to buy into the "need" for this kind of stuff. Clunky leaf springs don't work worth a damn...and more importantly, won't impress the lookie-lou's!

Oh wait...the economy is back down now so leafs work great...again! LoL

 

This isn't new any more - introduced over 4 years ago.
http://www.hotrodandrestoration.com...ses-new-universal-gasser-ladder-bar-subframe/

Not that it matters but the center joint isn't tri 5 only specific.
Ladder bar vs leaf spring isn't really the question however it makes for a great debate.

There's a whole lot of business going on it that center joint for sure.
One can almost see how the guy who designed it read one of the Hamb discussions and tryed to make everyone happy

 

I think you said EVERYTHING right there!
A lot of business going on and this joint addresses every necessary movement on an individual basis...while Fords design handles all movement with a singular simple joint at the front of the torque tube.
Oh...and that Ford joint also allows the driveshaft to elegantly pass directly thru the middle while it handles all the movement going on around it.

Clear winner: Mr Ford! Haahaha

I know, I know...it's NOT really the same thing because the torque tube is what we need to get rid of usually, due to the problems with engine swaps etc...but its nice to give Henry a shout out now and then, just to show how brilliant these old designs really were.

Back to the stuff at hand...I see no reason that something like a P&J ladder bar setup couldn't be rigged with adjusters at the top rear joint and accomplish everything this joint offers at less cost, less complication, increased durability and look cleaner doing it!

 

Turn the Heims 90* so they are vertical, lose the pivot mount and mount the Heims separately to the crossmember like everybody else does and it would be fine.

 

Very COOL setup, all forward movement transfered through one big center, pivoting bolt, pushing on the crossmember, totally adustable everywhere! very nice !! Chris

 

Bill, the Pete and jakes setup works but it has some drawbacks.
The bars are set up as a triangle and joined. When you extend or retract the legs via the clevis or a turnbuckle fitting to fine adjust the pinion angle or center rear the wheel, the short triangle leg gets larger or smaller. When that happens the bars need to be stressed into submission to get the bolts in the holes. There is exactly only one place that everything fits and technically there's no free adjustment. Since the gusset is placed 2/3 of the back from the pivot, forcing the 7/8 bar around ain't easy. And every adjustment requires removal of both bolts, then another fight to get them in see if it was enough. This messes up the threads eventually. If you've never played with them this probably doesn't make sense.

Then there's the angled connection at the front. I made a mock up of this and you'd be amazed at how much the axle ends need to move around >To center < Or away from center> when the crossmember needs adjusted up or down in relation the the axle c/l in mock up. In mock up, this triangle adjustment makes movement of the axle ends and that will move the axle c/l forward or back a lot more than you want it to.

On the road as the suspension works, the c/l of axle to c/l of crossmember is constantly changing in the height relationship. Those bushings really need to earn their pay.

 

i think it looks pretty cool

 

The thought that is running through my head is this.

Just because it has been designed of a race car does not make it safe for the road. Race cars are typically run for an hour or two on a VERY flat road.

A daily driver has to deal with a LOT more stresses.

Think of it this way. Will the joint system survive hitting a deep pot hole or large bump in the road while turning a corner or under heavy braking.

I my opinion this system will fail at either the Heim joints or the center bolt. Even if a grade 8 or above bolt is used since the higher the grade bolt the more brittle they become.




Singlefingerspeedshop.com. Detroit

 

There are a bunch of connections that make me shake my head on a hot rod.

First, the entire weight of the vehicle is riding on only 4 3/8" bolts in the spring shackles. Modern shackles have 9/16" bolts.

The Clevis pins for radius rods and ladder bars are 3/8 bolts and control the front end that the steering is attached to. They stem off every bump and you count on them too hold the axle that holds the brakes to the car so it will stop your ass. Thats the entire braking force applied in shear on those bolts.

You also count on those 3/8 bolts to transfer the torque multiplied by the Trans and rear end gear ratios into thrust against the frame to pull off your hole shot. Or even wheels up launch. 400 lbs of torqu thru 2.x first gear and 3.x rear gear divided by tire diameter in feet is a whole bunch of torque on those 3/8 bolts also in shear.

Anyone else think its Kind of funny how there's 2 big ass U bolts into a substancial crossmember to hold a spring to the frame and then dinky 3/8 bolts to hold the axle to the spring? It obviously works and works well its just funny

 

I agree about the shackles. Doesn't make logical sense.

The other bolts, I think that the load is spread over a wider area with the brackets and bolts so the stress is less.

One bolt taking all the concentrated load will always be weaker.

Martyn


Singlefingerspeedshop.com. Detroit