Aluminum bodies' strength

[juanone]

Could someone help in clarifying the strength of the aluminum bodies?

I have heard many times about how weak and vulnerable the aluminum bodies are to dents and the such. I have , however, seen a lot of archive pictures of the original cobras and many times the vehicles have a lot of the racers lean, stand and often seat on their cars' bodies. If they were so flimsy wouln't they avoid doing that to begin with. I have no personal experience in this matter and would like to have one of you guys with original ones or continuation or new series Shelbys to clarify this matter. Are they really that weak of bodies or is it just a prception and rumors started by people that have very little or no knowledge of the facts.

Please help clarify this matter.

[Excaliber]

I've seen a lot of pictures of the race cars "back in the day" with plenty of dents too! One reason for that was: They WERE race cars, they had no idea one day they would be "icons", they just chopped, cut, welded or improvised with what ever they had to get the job done.

Ernie

[juanone]

I wonder if the aluminum bodies of today are stronger?

The aluminum bodies that Shelby is using today are they being fabricated by Kirkhams? And if so are they stronger?

[Excaliber]

Sorry, I should have mentioned that!

The Kirkham bodies used by Shelby today are thicker than the original and are noted for being much more "dent resistant". Bear in mind Kirkham was/is not the only supplier of bodies to Shelby, all though by far the largest.

As to the "other" body manufacturers supply to Shelby I would ASSUME they to are using thicker metal than original. Kinda like in the days of the original and still true today, not all Shelbys are created equal!

Ernie

[Woodz428]

Aluminum isn't neccesarily weak, but since it isn't a stress part of the car it flexes probably more. It's the flexing that creates the weaknesses, except for the rock dings, that are likely in a hand hammered body. Aluminum has a lot lower fatigue cycle than ferrous metals, that's why the factory motorcycle race teams throw their frame away (actually probably back to the factory for analysis) after a certain # of races. I am not extremely familiar with the Kirkham body,but thought they were die stamped, which with the thicker material should make it more uniform and give more strength.

[Eddy K]

I was at the Spring Fling a couple of years ago and there was a woman there that had brought an original 289 Cobra down from Mich.
She was scared to death that some one was going to lean on her car. She told me that the aluminum was paper thin.
I also remember a guy from Bowling Green who had a Cobra in the sixties. He dated the daughter of the Ford dealer in our town.
It seems some one leaned on his car and put a dent on the rear quarter panel.
I remember the car. I don't remember seeing a dent in it although it may have happened.

[Back in Black]

It's gonna be a nightmare to have it repaired... fiberglass is relatively easy..

[Thorin]

Hay Back,

Remember Jamo's post about when they went to Utah and someone from Kirkham's took a hammer to the body and fixed it in a matter of minutes? Minor damage may be a lot easier to fix in aluminum than fiberglass - not sure about the big stuff.

Jamo - jump in

David Lowell

[csx700?]

the aluminum bodies do add strength to the overall chassis as the aluminum body acts as a stressed member.

[computerworks]

Originally posted by Thorin


Hay Back,

Remember Jamo's post about when they went to Utah and someone from Kirkham's took a hammer to the body and fixed it in a matter of minutes? Minor damage may be a lot easier to fix in aluminum than fiberglass - not sure about the big stuff.

Jamo - jump in

David Lowell

David.... great memory!

During our "Gashole" Summit at Kirkham last year, one of their craftsman (Tyson) took a hammer and bashed a body in several place with a big hammer...unsettling, at best.

He then proceded to demonstrate how the sheet metal has quite a memory and, with the proper tools and skill, made the dents disappear in a short amount of time.

Of course, if you hit a guardrail, it would be a different story, but minor repairs are a snap. (kind of)....

[Excaliber]

Ouch,,,OK he fixed it, but man does that pic make my skin crawl!

ha ha

Ernie

[PatBuckley]

Sorry if I come across a little grumpy here, but how can some of you guys - in this case BinB and Excaliber - answer a question that someone is seriously asking and you don't know your ass from a hole in the ground?

Do you feel that you have to post something even if it is a pure guess?

I just don't understand.

Pat Buckley

[Back in Black]

The answer is that if the damage is not in the right place, the entire body will have to be pulled to repair it without bondo. If the body is in the bare alum config then this becomes imperative. Certain damage locations require repair from the INSIDE out with the body pulled, also.

As I understand it, the location of the damage is critical to the feasibility of "easy" repair.

I like aluminum but it is NOT as easy as fiberglass to repair, overall..

[computerworks]

BnB...I think it's clear that you've never seen one of these cars.

There is NO body to pull; the body panels are wrapped and riveted on to the frame.

Additionally there is really no spot on the body that you can't reach from the inside by dropping an inner panel.

Agree that if you slam into the butt end of a guardrail...you have a major repair... but dings and dents are doable.

[David Kirkham]

Gents,

Just the other day we fixed a rather severe whack in a customer's car. Someone backed into him and smashed his headlight in about 3 inches. If the car would have been made out of fiberglass, there is NO DOUBT the entire fender would have been shattered.

Shattered glass is almost impossible to repair without grafting in a new piece. As is was, the damage was COMPLETELY repaired in 2 hours. The only problem with the repair was the side we fixed looked better than the side we didn't!

Now, the body was bare aluminum so the repair was complete--no bondo. Now, as no one drives "Bare Naked" fiberglass cars around, fiberglass would of necessity HAVE to be painted to completely hide the repair--an additional cost of many thousands of dollars. Bare aluminum, well like I said, the repaired side looked better than the side which wasn't hit. I guess I tried too hard to make it look good.

As for backing into guard rails...

I think we have all seen the myrid pictures of fiberglass cars which have been posted on this site--shattered in a million pieces with lots of body parts missing and scattered all over the road. I'll take repairing an alumium body which has been backed into a guard rail ANY DAY over a fiberglass car which has been subjected to the same accident.

As Ron said, just pop the interior panels and smack the dent back out. Granted we have a lot of experience with aluminum. I am happy to say, I am not nearly so experienced with the Bondo Repair...

"Don't touch my car, sit on my car, etc..."

I have pictures of women laying down (is that the correct verb) on the fenders of our cars. No dents, no bum prints, no finger prints, etc.

Original cars were extremely fragile. Ours are not and are quite tough and resistant to denting. We use a thicker aluminum sheet and a much stronger alloy. The original cars were pure aluminum and had the strength of a wet noodle--ours are remarkably tough.

Now, I have seen some of our car bodies which have been severely abused and got dented. I am positive the same treatement would have broken most fiberglass and got the offending mechanic dropped head first into a bucket of 90 weight gear lube by the owner if he ever saw the car abused that way.

I have sat on the fenders of our cars many times. Now, I do not sit on the cowl or cram my knees into the doors or the sides of the car. But, how many of you handle your nice china as if it were tupperware. (No pun intended here). Let's face it, you should treat anything with this much value with respect, regardless of what it is made of.

The only time the body is EVER pulled off of an aluminum bodied car, (I'm speaking of our cars and original cars here), is when the car is totaled and the body needs to be replaced. No one in their right mind would take the body off for any other reason. There are very few accidents which require the removal of the body. Any such comparable accident would certainly require a call to your replica maker's fiberglass shop for a new body.

David

[excelguru]

Good post, David. Which alloy do you guys use?

[pderouss]

I am with Computerworks and David Kirkham.

Firstly the aluminium used today is 16 guage rather than the 18 used originally so is much thicker and stronger. One of my other cars has an 18 gauge body and the slightest pressure will dent it.

In terms of repair all the panels can be accessed from behind so are easy to get to. Last year I saw a 427 that had received front and rear damage both before and after its repair. When finished it looked as good as new and no new metal had been added - they just used a lot of skill to bring the crumpled areas back to their original shape. You will not be able to do that with a glass body.

[Turk]

You wouldn't HAVE to.

I own a alloy car, and I can't say I have the same glowing opinion of the metal as others. My experience with aluminum over glass is far different than exhibited in here.

TURK

[pderouss]

Turk.

Do you want to tell us more about your experiences?

[Excaliber]

As to bodies NOT supplied by Kirkham, I wonder how thick (or thin) some of those were?

And what did McCluskey use for his cars?

Ernie

Major EDIT to promote peace and harmony in the family.