The axle under Metalshapes roadster looks about like that. He has driven that car hard. I remember him telling me he could tell that it flexed, but it has shown no signs of failure. His also has a more stretched drop area. http://www.jalopyjournal.com/forum/attachment.php?attachmentid=457822&d=1214102132
Four-thirteeen must still working 'in the field' and is correct. Generally, shear failures occur at the ends near the supports and bending failures generally occur in the centre. Is it stronger than a stock shape ? NO. Will it fail before a stock shape? No doubt in my mind. Perhaps one of the currently employed structural or civil engineers around here needs a project to shove through his beam ****ysis programme.
I saw a car at a show about five years ago that had the holes drilled in the axle what looked way too large of a diameter so that no web at all was left where the holes were, and the axle had obviously bent right at one of the holes -- the hole closest to the driver's side spindle. It didn't break at least, but it was bent, and the wheel on that side had a terrible camber problem. It was an otherwise nice car. You could tell the top of the hole sort of squished up like silly putty and the bottom just bent. With no web at all, it isn't an I-beam anymore, and just two thin parallel bars with space in between. When I drilled the holes in my axle, I didn't want to lose too much of the web, so I drilled holes that were about 7/8" or 15/16" diameter (can't remember exactly). If it's a real forged steel I-beam, and not a cast one, and it's a really light car, it might be okay, but I'd stay off of bumpy roads and check the camber pretty often in case it starts to bend up.
My friend has an axle done like this on his old flattie powered FED. Its like a flexible flyer but hasn't broke in all these years, (probably from the mid 50's). Would I drive it on the street? Your kidding right?
Seriously my thoughts are the axle is fairly safe Being into axles like I am, I pay attention to any info I come across. I tend to think they are way over engineered in the first place. (see pic of twisted one). I think ford built them to handle rougher roads and more weight than they will be subjected to in todays world. Iv yet to see or hear of one that has broken.
It looks a lot like mine. Mine was run under a '55 Chevy for a few years and did all right. I don't think the weight of my Bantam will bother it. Flatman
DUDE!!! if your where FU#@ing worried about SAFE! then you wouldn't be building a rod would you? either PUT IT ON! or go buy a Volvo .
I would NOT be very comfortable driving a car that has that axle in it or be be driving next to a car that has an axle with that much of the web removed. Local buckleing would be a big issue with any kind of impact since there is such a long section of unsupported flange. It "might" last forever BUT.. it also "might" fail and kill you or someone else. Why risk that if you don't have too.
The OUTER parts between perch and spindle have had their original heat treatment destroyed and the bending lever arm (there's a better term for that...) simultaneously increased. I think most stress will thus be absorbed in twisting out there, outside the rigid points created by the perches. A dropped original axle is sure as hell weaker than a stocker at the ends for the reasons above, and I've never heard of one failing, not even the most horrible blacksmithed ones.
WTF? If you put it on a fair to medium weight car, she should be OK. If you put it on aheavy weight, she won't be. However, to be absolutely certain, send it to me and Ill check it out by using it on my car first.
I know a guy that has a '32 heavy axle that is slotted about like that on his daily driver hot rod, and he hasn't had any trouble with it. It's a forging, so it's pretty stout...even with slots cut into it. If you're worried about it, have it magnafluxed.
The "look" is a vestige of early 60's drag cars like the Fiat pictured. Note the motor is set back at least 50% of the wheelbase, leaving very little weight on the front end. Worked just dandy on altered and comp coupe cars, and of course the street rod guys always want to look as cool as the racers, so the "look" wound up on street cars as well. I'm not going to say if their safe on the street or not, but there seems to be quite a few more comments on the positive, than the negative.
A buddy of mine had one on his 32 truck he bought you could watch it twist if you turned the steering wheel while not moving. That being said never had a problem with it drove it for over a year like that and sold it the same way.
Why could`nt you add some metal back ? Maybe some artsy inserts or something that would add a little more strength.
Holes are inherently stronger than slots. That axle works on the drag cars, because their real light in front. The more weight you add, the bigger the risk you're taking on the street, unless you can avoid every pothole in the world. I'd only run it in 1/4 mile increments or hang it on the wall. Good Luck.
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