Tube front axles safe?

[Bearcamp]

Right now I'm running a tube front axle kit from Speedway with the 3 piont radius rods. I was told that the tube front axle with the 3 piont rods are unsafe. Is this true or are they okay? I didn't really run it on the road yet but soon will be ready.

 

[AEROCOLOR]

I`ve always heard the rule is 4 bar w/tube or hairpin w/beam axle.
It has to do with the ability of the axle types to flex.

 

[donsrods]

I've heard that theory too, something about I beam axles being able to twist and a tube axle won't, so they break. But I don't think I have ever seen one that broke, and there are a million T buckets and other cars running around with them. My Son Don has a tube axle on the front of his T bucket, and I wouldn't let him run one without saying something if I felt it wasn't safe.

It is like everything else we rodders do, by just what they are our cars are not as safe as a brand new car with airbags, crumple zones, etc, but somehow they do great for the most part.

Don

 

[Paul_J]

There was a huge debate about this on another message board and when all the dust settled the evidence was just not there to say "Unsafe".

What evidence was available did show some wear on the clevis and attachment holes from the back and forth stresses. Still there were no broken parts.

I could see this being an issue if you used your car as a rock crawler but everyday street driving isn't going to be a problem.

BTW, ever try to twist an I beam? Those stresses are still there but not as severe.

 

[Blue Eyed Devil]

They are fine. I ran one on the T Coupe in my avatar with radius rods for years. Lots more things to worry about than that...

 

[vtrodder]

I have seen two on a vw that broke and cause serious injury. Seemed to have broke where it curves from the bottom up to the spindle, and expecially stay away from the chrome ones, JUNK im my opinion.

 

[donsrods]

That is VERY odd, and I would love to see pictures. When you say VW, I guess you mean the kit they sell to put a tube axle under a bug ? There is something missing from this story because for you to have seen 2 of them is odd in itself,

Like I said, count how many T buckets and other cars are using them for a lot of years with no problems, including our own.

Don

 

[Paul_J]

He's talking about the axle being broke bast the boss where the wishbone or radius rods attach. Although one was on the other side of the boss. One I believe was a Magnum axle and I know of one that was a Superbell. They didn't break due to a bind occurring in the suspension components. These failures were due to material and quality issues. They were all I beam axles as well and not the Tube axles.

One of the cars was this one and has since been rebuilt with an IFS. You can see the aftermath here as well as a few more broken axles.. http://volksrods.com/forum/showthread.php?t=30628&highlight=broken+axle

Here's another

Close up

 

[HOT40ROD]

Looking at both those car. I am wondering if the broken axle cause the wreck or did the wreck cause the axle to break.

 

[Paul_J]

I know for certain the VW crashed as a result of the axle breaking.

 

[Bamamav]

..... and expecially stay away from the chrome ones, JUNK im my opinion.

I remember reading In Hot Rod or Street Rodder several years ago about chrome suspension parts becoming brittle from the chrome plating. It was something about hydrogen reacting with the chrome or the steel, and you had to do something to put the tensile back into the steel after plating. That could be the reason those broke, they weren't properly treated after plating, I don't know.

On another topic, but boy, I wish I had of seen a Bug built like that back when I was hot and heavy into them! That is cool!

 

[vtrodder]

DO NOT BUY I BEAM AXLE FROM SPEEDWAY, the axle caused the wreck.

 

[Shea Laking]

I remember reading In Hot Rod or Street Rodder several years ago about chrome suspension parts becoming brittle from the chrome plating. It was something about hydrogen reacting with the chrome or the steel, and you had to do something to put the tensile back into the steel after plating. That could be the reason those broke, they weren't properly treated after plating, I don't know.

On another topic, but boy, I wish I had of seen a Bug built like that back when I was hot and heavy into them! That is cool!

It's called "hydrogen embrittlement." Hydrogen molecules are trapped in the steel part during the plating process, causing the metal to weaken. There is a process by which the part is baked to a certain temperature after plating, which will eliminate the hydrogen-literally "bakes it out" of the part.

Hope this helps...

Regards,
Shea

 

[Bamamav]

It's called "hydrogen embrittlement." Hydrogen molecules are trapped in the steel part during the plating process, causing the metal to weaken. There is a process by which the part is baked to a certain temperature after plating, which will eliminate the hydrogen-literally "bakes it out" of the part.

Hope this helps...

That's it! I couldn't remember the term the other night when I posted. From what I read on the VW, it had a CAST axle. I wouldn't trust a cast axle on anything larger than a lawnmower. Forged or a tube axle with forged ends would be the only way I'd go.....

 

[Torch]

Looking at both those car. I am wondering if the broken axle cause the wreck or did the wreck cause the axle to break.

any suspension component like an axle properly manufactured would never break. it would bend first but never just up and break.
That's the universally accepted manufacturing standard with any critical component...zero failure