Welding Tips and Tricks

Guys,

This picture is from a friends racecar that impacted the wall. This particular tube was a support tube essentially the equal of a core support for the radiator area. Just wanted to post a picture in hopes to have the weld diagnosed or looked at. To me, I'm not certain the weld should have broke like this but you guys know more about this than I do.

Disclaimer, I don't work on race cars.

Looks like since it was a radiator support it was only welded half way around - I don't see weld on the backside.

The break likely started at the end (or beginning) of the weld and zippered the rest open right down the center.

I agree.

While there appears to be excellent penetration in the weld, since it's not welded 100%, the failure began in either a "cold start" with inadequate penetration, or a crater in the tail of the weld. The progression of the ripples suggests this began at the start of the weld.

As this was ancillary structure, rather than primary structure, I'd not be too concerned, beyond a general inspection of all frame welds, and a carefull inspection of welds near the impact. This weld did it's job well. The tearing/separation here absorbed a great deal of the crash energy.

Steve S

no expert here either. But it does look as though there was too much downward force on the pedal toward the center line of the car and not enough force on the pedal next to it.
was the tubing cold when it was welded and did it cool to rapidly?
Don

Your friend didn't do too much damage.

I entered a raffle for a Ferrari 458, the draw is next month.

I hope that they steer a bit better than the guy in this video.
https://www.youtube.com/watch?v=4tiudvxTGes

These guys took a video of the car being raffled in the mall.
http://www.youtube.com/watch?v=_zZGbWTSohc

mbenzocaine wrote:no expert here either. But it does look as though there was too much downward force on the pedal toward the center line of the car and not enough force on the pedal next to it.
Don

I'm not sure...must be the wall designer's fault for making the wall stop him too abruptly...

In today's wussified world, the wall should be more of a polite suggestion to stop.

mbenzocaine wrote:no expert here either. But it does look as though there was too much downward force on the pedal toward the center line of the car and not enough force on the pedal next to it.
was the tubing cold when it was welded and did it cool to rapidly?
Don

I appreciate everyone's reply here with the exception of yours Sir. The gentlemen whom is a dear friend of mine that drove this car has thousands of passes under his racing resume, many at E.Ts few of us ever achieve in similar cars.

* You don't know the conditions or the situation beyond what I have provided and were quick to throw judgement at someone you don't even know, much less probably something you dont' even do on this level.

Carry on.

rsears, we did not mean insult you or anything....
You came here asking us why the weld failed, correct?
We mentioned some of the possible causes for weld failure....
We are not trying to put anyone down on their skills and experience,
We try and share our experiences and knowledge...
Our Forum is here for people to ask us questions and our opinions.
We try and help people get started on the right track, if you will....
We try and answer peoples questions, based on the information you provide.
Not everybody's opinion and experiences help you in the exact way you need.
No one on this forum is trying to insult anyone. if you ask for an opinion, you get a opinion....

John

Easy, now...

rsears expressed grattitude for the replies, with a sole exeption.

I would think, reading mbenzocaine's response, it was intended to be humorous, but without the smilies or winks to show it, it was taken as a "snotty remark" and failed in humor.

Let's not elevate this to "drama" on what is likely a misunderstanding or miscommunication, please.

Steve S

Ok.
sounds good, I hope we all stay friends
I wonder how much force/collision/impact was put on this weld....

Time wounds all heals....
John

AKweldshop wrote:Ok.
sounds good, I hope we all stay friends
I wonder how much force/collision/impact was put on this weld....

Time wounds all heals....
John

It's impossible to guess, but if this structure saw 10 Gs (small for a front impact) and simply "tore" without crushing or collapsing, it did what it was designed to do. I'd have to say it was designed well.

Designing for strength is one thing... I do it often. Designing to absorb progressive impact forces (absorbing g-forces in an impact) is way out of my league.

Steve S

Hey,

Humour is a difficult thing to pass on via type, hence the need for the much used LOL or . No one i have seen on this forum in 3+ years has meant to offend anyone. Quite the opposite of facebook, which can be quite a cesspool sometimes. So go in with an open mind.

Back on the topic, as otto says, the cage most likely performed as it was supposed to. I work for a Military contractor, and having seen some of our vehicles that have undergone blast tests, that is a thing that no one can plan for, especially with IED weapons. 18mm thick quenched and tempered steel, caved inward like a deflated basketball.

Mick

rsears. It was right to call me out on my careless judgement of your friends driving skills.
Will you please forgive me?
Relating to people I'm often like a piece of aluminum caught in the Cross-fire of electrons of a tig torch.
As the current and subsequent heat go up there is a cleaning effect. Soon I become reflective, just like a mirror. It is then that the Creator sees His image in me.
Don't fear the heat. Fear Him.
Peace, Don

Yes, I agree with you.

It's impossible to guess, but if this structure saw 10 Gs (small for a front impact) and simply "tore" without crushing or collapsing, it did what it was designed to do. I'd have to say it was designed well.

Designing for strength is one thing... I do it often. Designing to absorb progressive impact forces (absorbing g-forces in an impact) is way out of my league.

Steve S

Hi,
I really appreciate you Steve. The layout of the picture is good, normally TIG welding is frequently used for high quality, precision welding. That's good thing you can suggest.

David
http://aluminumrepaircom.weebly.com/

It appears that if the welds are splitting and the tubing is staying intact, not even bending..... The frame may stand to lose some weight. Also, crumple zones are designed to collapse not break. How do you design the front end of a car to absorb the impact and not bounce off the wall. It would seem very important to protect the radiator from crushing, cracking and breaking on impact. Is it possible to design the front end using sacrificial fasteners for the radiator so that it may break free and float in the supports on impact? Just some thoughts.
Don