It scares me. Just FYI, hairpins turn an otherwise innocent axle into an anti-sway bar. Neither the axle nor the hairpins are really designed for this. It's why four-bars were invented. Cosmo
That is pretty frightening, I wouldnt touch it, aside from removing it. Regarding i beam axles twisting. Has anyone ever put a hairpin on an i beam axles and actually twisted it to see if the deflection is in the axle, or is the hairpin deflecting? Just curious, but I do imagine there is a fair bit of force involved.
More than anything, I question the welding and how the connection thins down as much as it does where the bracket and old wishbone meet. I wouldnt run it.
I always thought felt the modern use of 4 bars came about because of the Super Bell tube axle. Back to the OP question, hairpins and split bones have been used with I-beam axles for decades; that said, the heim ends and bulgy ended tubes pictured does not really look very smooth.
Heres my deal on this, 1st I don't disagree with anything being said besides the welds, their strong. But these hairpins for the most part was built in the late 60's for my uncles hot rod and never finished and given to me, since they had sentimental value I wanted to run them. they're 3/4 solid with 1/2 threaded holes, not perfectly centered originally is why I have enlarged the ends. The Reason I was mainly wondering was side to side movement and I am not too fond of the 1/2 hiems although I think their rated at around 7k lbs each. Anyways I wanted to used them for the above reason but slowly shying away from the idea, but didn't know if anyones done this.
Maybe consider that the 3/4" solid rod has considerably less resistance to bending and also will not flex like the 7/8" tubing usually used.
I also thought about milling down that 3/8th plate welded to the end of the wishbone to 5/16 then buy those clevises actually used on hair pins and using them. I could make the clevis but they wouldn't be hardened
If the "gusset ran from the top edge of the old wishbone to the top of the "batwing it would nearly double your " connection "cross section....would be a hell of a lot stronger... Posted using the Full Custom H.A.M.B. App!
First, on the weld, I blew up the picture as big as I could and it looked poor, but that could be the shadowing on a not high res pic, so since you see them clearly, I'll go by your judgement and take it as a solid weld. Second, it looks to me that where its welded (not the weld) looks shaky that the pressure point from the where the rod ends sit outweigh the area of connection between the two welded pieces. Think of you holding a 3' long rod in the center steady while I grab it by the ends and rock it back and forth. Past that, I would have little issue removing the needed metal on both sides to make that bracket ENDS 5/16" (not the whole bracket). You will gain strength on the bolt by it becoming a double shear with the clevis over the single of the rod ends.
#1. The heims should be in double shear in that application. #2. I've got to question the bars, they look hokey to me. #3. How good is your welding? #4. Big clevises like P&J or SoCal use would be better, then you wouldn't need the double shear. But I still refer you to points one and two. I forgot to add, what's at the other end? It's important too.
The one thing that jumps out at me is that spot where the old bones were cut off and the new plate welded onto it. That looks like a really stressed spot and, if anything, that is where it would break. I would feel a lot more comfortable if that plate was moved up, the old bone section eliminated, and ears welded onto the plate to go on top and under the axle. That spot looks problematic to me. Don
Of course 4-bars don't really have all the degrees of freedom a front end needs either. They rely on compliance in the bar bushes; otherwise they'd bind in roll at all points in vertical travel but one. That isn't the case with a 3-bar location with a lateral-locating device like a Panhard bar, nor with a triangulated 4-link. I don't think I've ever seen a triangulated-4-link front end: no reason it couldn't work with fore-and-aft steering, if the drag link hugs the parallel link on the driver's side. As for the OP's question, the Heims are redundant and a potential source of lost motion if they deteriorate, compared to clevises. Single shear shouldn't be a problem if the fasteners etc. are sized appropriately, i.e. somewhat bigger than in double shear. Yes, the I-beam axle can twist and yes, it has a consequent effective spring rate in roll, like an anti-roll bar. The length of the hairpins would make that spring rate too low to be of much consequence, though. In roll the top and bottom chords of the hairpins are in compression and tension, in which they are a lot stiffer than the axle is in torsion: the strain is going to be in the axle, not in the hairpins. There will be a very small amount of lozenging resulting in a bit of left-right flexing in the hairpins, near the clevises. Strictly, the clevis pins should be vertical to allow for that. There are two problems with binding, and catastrophic component failure isn't one of them. Unwanted elastic behaviour is one, springiness where you don't want it; but as we've seen the torsional elasticity of the axle is unlikely to amount to much in this case. The other is fastening holes wearing oval and the whole set-up becoming sloppier and sloppier over time. Those improvised batwings seem a bit ham-fisted to my eye. Nothing wrong with cut-down wishbones as such, but it could be done more elegantly.
I just think this looks like shit. Just being honest.. But whats wrong with a split wishbone instead?
The welds are just about at the highest stress point, and the narrowest part, too. I would find some fresh 'bones and split them, or purchase some "real" batwings. That single plate wing setup is liable to twist and crack, where a double wing is not subject to twisting the bolt loose.
This twisting motion in the 4-bar bushings is why the GM rubber lined bushings used in P&J's original bars failed and were replaced by urethane bushings (and why the cheap plastic bushings don't hold up either). Lot of movement in a 4-bar that is not evident at first look.
Give the weld a fighting chance, add some re-enforcement, a gusset would help spreading the load, IF you use rods ends, try to use double shear, if not at least a safety washer. Personally, this looks cobbled together to me.
Are you asking about the batwing? If so yes I have done it and yes it works. granted that was long before the internet and before the time when people who have never done it became experts on the matter. The deal is that you need to be sure that the batwing is welded well, the weak spot is the union of the batwing to the forged end of the original Ford radius rod. We used to stick weld them with Lo-Hydrogen rod, something along the lines of E-8018 or E-7018. But I have heard of guys welding them with farmer rod ( E-6011) as well with good success. Good luck.
If you have any doubts about the "batwing" buy a set that are welded by a trusted supplier, change out the Heim ends to forged clevis and install them on the Hairpins, Just insure as has been stated many times above that the welds (on the threaded adapter) are good and use a Jam Nut (not seen on the picture) on each clevis to keep them tight and not work the clevis's loose as the suspension works. I would also like to see the end that attaches to the frame/radius rod bracket. I also like to see a plate welded from the upper to lower length of the hair pin to help the integrity when braking/turning and applying forces when driving. Long answer but sentimental feelings aside I rather be safe by over building. All this said the welds MUST be perfect!
If you took the assembly off the car (Hairpin & bracket) you can easily rock things back and forth due to the use of Heim joints at the connection. Because of that free movement in the Heims the bracket will tend to hinge around the perch bolt and compromise the looks, strength and alignment of the car. Tight perch bolts alone isn't a guarantee that the bracket won't rotate over time. I've had a couple that were surprisingly easy to reposition when splitting a wishbone. Could always weld to the axle I guess but thats a bit hokey... If you used clevis joints instead there would be no movement at all possible at the perch pin, and the joints also become double shear at the hairpin. Two wins...plus it looks cleaner as well. I can't honestly say I'm loving it but as long as you're happy with the welds and design then I don't think we should write them off simply because they don't look bought or something. Be sure that things are strong beyond what you think they need to be, just for peace of mind.
so I get the connection to the orginal piece, but it just looks sketchy to me. and rembmer the car was never finished so I'm guessing it was never run like this. I'd consider other proven/safe options and keep those as wall hangers. the last thing you want is a catestrophic failure that totals your car and potentially hurts you and or your passengers.
It will work for a short period of time then problems will develop with your first panic stop. Hang them on the wall and use bones.
I'm hearing a lot of good stuff here, I understand what some people have said about the batwing/wishbone, I should have mention that the bone was milled into and batwing slid into this. and as far as buying stuff, im like many 23 yr olds, enough money to pay bills. but on my side my family owns a welding and machine shop, nice welders, monster presses, lathes, a lotttt of stuf im fortunate to have, so if its make able that the route bc I get most of my metal free. my true concern is with not having double shear on this, but at the time, this is what I came up with. I was going to make clevises but I haven't learned how to use the oven deal to harden stuff. but seriously wether I screwed up this time, I don't see what some people are so quickly to give into buying stuff, I understand a safety issue, but that's why I was asking. you don't learn until you try, this was just my first attempt
I don't especially like the welding but the slot does help but where are the lock nuts on the heim joint?? If you don't use lock nuts you will just beat out the threads and then you will have more junk than you have now. Rex
I really think the Hiems are a bad idea. The batwing can turn on the perch bolt and the Hiems will offer no resistance. The loads are appied off center unless you cock the batwings so the Hiems line up with the perch bolts and the hairpins. They can fold up on you.
I don't have jam nuts on there because I can't afford them at the moment but they'll be some on here If I keep this setup
The Jalopy Journal
