Featured Technical Broken Super Bell axle

Has anyone had any experience with Super Bell axles breaking? I had an incident yesterday with a very light impact to the right front wheel of my 32 ford which resulted in the axle breaking in two! I would have expected it to possibly bend but not break. It is on traditional hairpins with a super slide spring. I have included pictures

 

I've seen them bend and I've seen them break like that. Usually a pretty good whack to get it to do it. In any case Super Bells are pretty sturdy as they are cast steel, but they are cast so even if it's just a bend it's time to replace. I know it's obvious for yours but this is for anyone reading

 

It appears that you were very lucky that it did not end up much worse.

I am guessing this was a fairly low speed impact?

 

Wow! Looks like you were fortunate since that could have caused a pretty big problem. A lot to give thanks for there. I struggle with the idea of a cast axle and would much rather have forged. I have run multiple dropped factory forged axles and have yet to break one.

 

With the large amount of stock axles out there and the number of guys who are doing excellent drops, there is no reason to use a cast axle. Glad it didn't result in a major catastrophe, but use this time to install a forged axle.

At speed, this would have a true disaster.

 

There was a rumor going around that at some point in the last 15 years or so, these axles changed, either they were made differently, or made in a different place, something like that. Do you know when this one was made? I'd be curious to know if it is a fairly recent one.

It being drilled probably didn't help, but also (and I don't know the metallurgy on this) but I wonder if chrome plating also has an effect on it.

Either way, that's pretty scary, wouldn't want that to happen at speed. I've seen some incredibly mangled early Ford ones but I never saw one of those break.

 

Is that one of the Super Bell aluminum axles or cast, Forged axles don't break.

We had a accident in my '32 on the way to Goodguys and bent the Superbell tube axle, no one at the show had a axle for sale but one of the venders had the new Super Bell aluminum axle, it was pricy but I needed to get the car back on the road.

I felt like it was fine for a trailer car but not a real world driver, I sold the car after a few months I just never felt comfortable with the light weight axle.

• Weight: ~9.5 lbs.
• Material: 7175-T74 aircraft aluminum.
• Size: 46" king pin to king pin.
• Drop: Available with 4-inch drop.
• Variants: Available as fully polished or with drilled lightning holes.
• Application: Generally designed for 1928-34 Ford frames using 1937-48 Ford spindles.
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• Part #1100-F Super Bell Alum-I-beam Axle (full polish) - Pete & Jakes Hot Rod Parts
  The Super Bell Alum“I”beam is a computer-designed, strength-tested axle that combines a traditional I-beam “narrow upsweep” with a...
  
  Pete & Jakes Hot Rod Parts
  
  
  
• 
  

 

Drilling a stock Ford axle has been done for years with no issues. This is a great example of why you should not drill a cast axle.

 

It makes me wonder what the strength differential is between a drilled and non-drilled. Hope there were no injuries and not too much other damage.

 

^^^^^^ and that’s the truth….. chroming can also cause brittleness I’ve heard!

 

Wasn't there an issue with some knock off axles using a logo similar to Super Bell's and breaking?

 

The takeaway:
1. Don't use a cast iron axle
2. You don't drill a cast iron axle, ever (or buy one if that is even a thing)
3. Life is more valuable than a cheap cast iron axle
4. Real Henry Ford axles are cheap and safe
5. Aftermarket forged steel axles are safe and you don't risk killing people

 

I would be interested to see the ends of the axle, where it broke. It may have been cracked from a previous impact.
Is the axle cast steel, or cast aluminum?

 

I'm glad you weren't hurt. That looks like a Superbell Aluminum axle. It's pretty thick in the web. It appears that when the tire struck the obstacle, it caused the axle to bend backwards, using the hairpins as a pivot point. It bent the axle in the weak axis of the I beam, and it broke in the middle of a hole. The weakest point. Not a good result. I agree with all of the above statements about using a forged axle. Cast parts are not as ductile as forged parts.

 

The break looks like a casting (either iron or steel, hard to tell), and possibly suffered hydrogen embrittlement from the chroming process. I'm just glad nobody was hurt!

 

Yes about 20’ at around 1 mph

 

Not aluminum its a steel axle

 

That break sure looks more like a casting than forging as far as how it broke. But, zooming in on the pic, it also gets real fuzzy.

 

Here is what it impacted 1948 ford business coupe which was parked. The 32 traveled about 20’ at about 1 mph so definitely not high impact.

 

Try and stick a magnet to it and end the aluminum vs. ferrous speculation. Cast vs forged would be a little more involved to decipher from these pictures, but I have my doubts it's forged steel.

 

That center web in the "I" also sure seems thick to be forged at least looking through the holes.

 

A picture looking directly at the broken end of the axle will show if there was already a crack present before the event that broke the axle.
I have been around a lot of cast and a lot forged parts, they generally don't fail from a light impact unless they were already cracked.
However, IF the impact was the result of a crash with another car, even at a low speed, that changes the dynamics a lot. The last picture shows a boxed frame horn was also bent. If the axle was caught between the frame horn and the impact with the tire, that was not a light impact, especially if both vehicles were moving.
A pot hole in a driveway at 2 mph is a light impact. A head on crash with another car is not.

 

Excuse me,When I talked with Jim Ewing many years ago he ***ured me that using a forged axle under my hot rod is the safest bet, they don't have the record of cast axles failing, but again, I have never seen a forged axle break, Ive seen them bent but never broken. HRP

 

I know they look cool and have been around forever, but I have always been against drilling "I" beam axles. Drilling the web of an "I" weakens it considerably and I'm amazed that more have not broken. Now that most axles are being made in China, really is cause for alarm.

 

I agree.
Google "hydrogen embrittlement" during chrome plating...could explain a lot.

 

@ocool25 Take it as a cheap lesson. No Super Bell axles. No cast axles. No aluminum axles. No Hoffman Group axles. Get a Ford forged axle, and have it dropped to fit your needs. If you want it drilled, fine. That very well could have come apart at highway speeds, and you wouldn't be here to tell the story, or you could have taken out me, or my family. Do EVERYONE a favor and use a forged axle.

 

Does it have the Super Bell logo on it?

 

I purchased it in 2008