The quality of bens work is top notch, so presume it was the perch pin that sheared, but again I just speculating till we hear from a devastated Ben. pics from his build. By him posting this it shows he rightfully proud of his build and open to opinions of what went terribly wrong.
Workmanship looks A-1..... Hope to see the part that actually failed. I'm guessing it's an aftermarket part.
from facebook. Broken spring perch bolt. Said it had multiple cracks in it Sent from my iPhone using The H.A.M.B. mobile app
Now I want to know who made that one because it looks awfully similar to the speedway ones I have on my cars.. Sent from my iPhone using H.A.M.B.
The forces applied in stock type location and the way this one was installed are slightly different Even if it did snap in a stock type application the axle would catch the car , while I like this type setup as far as looks , this particular senerio has always worried me..
Sad to see a bitchen car banged up but great to hear Ben is healthy and safe. Cars can be fixed no matter how bad and can't wait to see Bens next build.......
Ah youre right. Forgot that it was a suicide front axle setup. All the weight of the front rests on those two bolts.. Sent from my iPhone using The H.A.M.B. mobile app
At least in my head- The load forces are very different from stock. The perch bolts look aftermarket-new and not Henry's stuff.
I have seen the suicide set up with brackets wrapped around the wishbone and act as a shackle mount. This would eliminate a single bolt mount but if a broken main spring the same issue would happen. The military used springs that would wrap around the shackle in case of a main spring breakage . Let's put our mind together and find a safer way and plan B using it....
I've seen some metal work on the HAMB that started out looking like wadded up tin foil and ended up being straight and perfect. I don't own the car but if I did I'd have to redo it. It's too cool to abandon. Good luck with it!
The stock perch and nut have a taper, we don't know what the wishbone mounted setup had, was there a nice radius or sharp 90% end on the sholder. Bob
If you run a normal leaf spring (not reversed eye) you can run a long 2nd spring leaf with a curved spring end.....sort of like a partial, 1/4th of an eye. So if the main leaf breaks, the curved end on the second leaf will catch on the shackle bolt to prevent the end of the spring from dropping and diging in the road surface. Saw this set up on a Dutch Eshelman modified a few years ago.
no no no its a cheap Speedway part..... engineering considerations do not apply when its cheap, cheap beats all but really I dunno where the part came from and I'm not going to diss a retailer for this (especially when the retail not manufacturer) Could you not run a catch wire from chassis to spring eye , similar to F1 cars that have to have one to stop suspension parts coming off?
The RB guys weld in a bung to the bones, then weld the perch solid on both ends to the bung. In order for that to fail it needs to both break the weld at the perch and the perch's pin.
A bit of extra insurance, however, even with the perch welded to the wishbone, if the perch failed and sheared where this one did, it would have probably torn through the weld and still come crashing down. I'm with thirty two, on the shear load perch design looking cool but my gut doesn't trust it like the stock load design. I feel the same way about underslung suspensions: they look trick but I don't trust the design where the entire weight of the car is pulling down/hanging on the leaf spring U bolt nuts. All said, I'm really glad Ben is ok and the car will see the road again.
Holy Shit - heard about this yesterday . . . such a totally Fxxxed up situation to deal with. And to think - this car was in my garage in July - for the Columbus GoodGuys show! It was a beautiful design . . . everybody loved it. Most importantly, I'm glad that Ben is okay and that nobody else was hurt in the car - or in other cars around it. Material things can be replaced - people . . . not so easily. It is easy to do Monday Morning Quarterbacking - so I'll take a stab at it. First of all, the original Henry design of having the perch pin vertical (well almost), puts a completely different load on the pin than having it horizontally mounted in a shear condition. The shear load on the pin is completely different . . . the whole weight of the front of the car wants to bend/break it off. So - even with forged parts - I'd be very suspect of this design. Does it make the car very low . . . and look cool . . . sure . . . but is it also a potentially dangerous application of components that are not designed to take the loads they are now under? I think the failure gives us a very good example of how changing a design (using the same parts) - can create a situation that we did not account for. In this case, a quite dangerous one. Secondly, the particular perch bolt that I see . . . sure looks cast to me??? Maybe I'm just seeing things . . . but it does have that "look". So -- now you take a potentially inferior part (from a materials and strength perspective) - and put extreme shear loads on it - then it breaks. Also, consider that this car has very few miles on it - imagine how over time . . . that the potential for the perch bolt failure could have increased (even with a forged component). Thank God he was not clipping down an interstate at 90 mph . . . he may not have made it out of that one. I'd love to do a finite element analysis (3D CAD engineering analysis software) of the original Henry design . . . versus this "in shear" mode . . . I bet the FEA model would show one Hell of a lot of RED on the horizontal perch bolt. Again - so glad that nobody got hurt . . . we should all think about some of these suspension designs and consider what might happen when shit happens. Lots of great comments on this thread about suicide front ends, failure situations, potential 'safety measures' etc.. It is good that we're all sharing and talking about it - even though it is one SOB for Ben to have to deal with. My heart goes out to him . . . Hopefully Ben gets a car back on the road - with a different front end setup. I wish him the very best!
After all that has happened to the poor guy let's not start kicking him in the nuts just yet. I'm sure he knows more about what happened than any of us. We can work out why and how to prevent it on his next rebuild of the car. Glad you did not get hurt too badly. Denny
I really am glad he's here to read constructive design ideas vs what was initially used. That's a lot of car to hang on that part, or even 2 of them (one each side). Suppose the car only weighs in at 2300#. Let's say 1/2 the weight is in the front (although some carry more than 1/2). Lets split that too, so we have 550# on that part while at rest. Anyone care to speculate the weight or force over a bump? Even slight dips in the road as it yaws front to rear, side to side, what's that load now? I'm not kicking something while down here, I just think this will open the minds of builders heading down a similar path. Years back I'd have clients that wanted their cars tubbed and they'd tell me "...nothing extreme, I'm not racing the car." Always the same reply from me, "Well we'll have to add some pretty serious bracing in key places." "But I'm not racing I just..." "You just plan to make 2 passes down the strip for every mile you drive, and that's not even considering the pot holes and shitty roads. How many drag strips have railroad crossings? Unexpected gymnastics required when that driver ahead cuts into your lane? How many semi trucks blow you off the drag strip when they pass you or you pass them?" So again, with all due comradery and support, that single mounting point isn't something I'd trust over average MI roads or unknown 2 lanes from coast to coast. Am I being an alarmist? Just a rare incident in this 1 case? A singular part failure? Right hand raised, it wasn't a lack of talent and execution. Looks very well built but not nearly robust enough to take a beating mile after mile. If I deserve it tell me to fuck off, but it would be nice to consider it so nobody else goes through this with even fractionally less luck, or at freeway speeds. Ol Henry was rather proud of his metallurgy, but even using his parts I'd like to see that load carried in a different manner, or in a way that some control remains in hand. Can't say enough how happy I am you're able to share this experience with us.
I I have done this also but , unless you are running a panhard on the front the broken spring will allow the front to walk and will pull the leaf away from the eyelet, but any extra measure made is added insurance, if the axle is hidden by the grill I'd be tempted to add some kinda limit stops
Its definitely good to talk about this...it could prevent another tragedy. The engine weight may have increased load as well. The Interceptor in comparison to a smallblock or flatty? I'm no engineer by any means but this is very important shit and a great many of you have been around this stuff enough to validly question something which may have not been considered in error...
Well one thing for sure, this will go down as the answer as to why this style of front suspension is called a suicide front end. Ben didn't show the mods to the spring hangers in the build thread but they may have been turned down in the lathe to have a 90 degree shoulder to but up against the radius rods. One has to wonder if a fatter bushing that had tapers turned into it to allow the stock Ford taper to fit in may be a bit stronger. One thing, the body was one that Flop pretty much assembled from scratch with new panels from Brookville an not for the most part at least and not 80 year old tin. Simply meaning that is probably more prudent to salvage some of the special parts and start over rather than try to fix that body. Hell, I just hope he doesn't throw in the towel and does rebuild the car. Maybe with a change or two and go again.
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