# Could a Car Be Made (Body Panels) From Bronze? **URL:** \ **Category:** Factual Questions\ **Created:** [December 14, 2008, 2:34pm UTC](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113 "2008-12-14T14:34:41Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Balthisar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/balthisar/32/2825_2.png) [@Balthisar](https://boards.straightdope.com/u/Balthisar)\ **Post date:** [December 14, 2008, 7:27pm UTC](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113/21 "2008-12-14T19:27:06Z")
> [@Huerta88](#): > > Most of the crash protection comes from the structural frame members, not the body panels. Depends what you call the body panels, and the type of collision, especially when talking about unibody cars which is the majority produced today. Here’s what I’d call a “body panel”: the front fenders, the hood, the doors, and the decklid or liftgate. Of these, the only thing that has no significant crash consideration is the fenders. Obviously well-designed doors are important to intrusion avoidance during a broadside collision (hint: North America has much stronger requirements than Europe does for doors). The hood has to be able to not detach and fly through the window and decapitate the passengers. There’s also the car’s body sides. Much of what you see from the outside looks like a body panel, but in effect it’s a huge structural element of the vehicle on its own. It keeps your roof from crushing in on a rollover; it contributes to lateral intrusion avoidance, and contributes to rigidity along all three axes of the car. As for whether a car body could be made completely from bronze, let’s see. I quick search indicates that at least several types of bronzes are suitable for stamping applications, which indicates that body structures could be formed. Joining them would be an issue, as mechanic fasteners would have to be used (e.g., rivets), or a completely new resistance spot weld system would have to be developed (too conductive). Since we’re making the structures from bronze, we could fall back to silicon bronze fusion welding, although this has environmental impacts and is expensive. So far, we can form the parts, and have a means to join them together, then. So, yeah, if we really wanted to, we could build a car body from at least certain types of bronze. The real question is, why would we want to, and if we really wanted to, would we want to live with all of the sacrifices that would be involved? Weight, safety, and so on. ---
**Author:** ![constanze](https://avatars.discourse-cdn.com/v4/letter/c/f9ae1b/32.png) [@constanze](https://boards.straightdope.com/u/constanze)\ **Post date:** [December 14, 2008, 8:05pm UTC](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113/22 "2008-12-14T20:05:43Z")
> [@beowulff](#): > > You could make car body panels out of rice paper if you really wanted to. They’re made out of steel for obvious reasons. Think about it. Although the famous [Trabbi](http://en.wikipedia.org/wiki/Trabant) was made from cotton strenghtened with plastic. Around WWII (when steel was scarce), a certain car was made from plywood. Obviously, today, crash tests have developed crumple zones and passenger cages to a different level than 40 years or more ago. Still, there is research going on to make large parts of cars from plastics and other mixed materials instead of steel. Advantages would be less weight, no rust, possibility of re-using materials (if they are clearly marked and seperated). For example, thermo-memory plastics used in car bodies would be far easier to repair than steel (that’s plastic that remembers a different form if heated - so to get rid of dent, you just point a hair dryer at it). ---
**Author:** ![constanze](https://avatars.discourse-cdn.com/v4/letter/c/f9ae1b/32.png) [@constanze](https://boards.straightdope.com/u/constanze)\ **Post date:** [December 14, 2008, 8:11pm UTC](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113/23 "2008-12-14T20:11:38Z")
> [@beowulff](#): > > None of which invalidates what I said. > The Corvette is a niche-market sports car. > Saturn has never been profitable. > The Fiero was a one-off. > Find me a mass-market (let’s say 75,000 units/year) car that’s currently in production that uses something other than steel for its body panels. Jsut because it’s not commerically profitable _right now_ doesn’t mean it won’t be a good idea in the future, which is why research is going on in that direction. Who knows how the material market will develop, e.g. who would have predicted how high prices for bronze rose recently? ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [December 14, 2008, 8:31pm UTC](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113/24 "2008-12-14T20:31:36Z")
> [@beowulff](#): > > None of which invalidates what I said. Well, it does invalidate your claim that the reasons for using steel are obvious. If they were, no one would even bother _trying_ anything else. ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [December 14, 2008, 8:43pm UTC](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113/25 "2008-12-14T20:43:25Z")
> [@Q.E.D](#): > > Well, it does invalidate your claim that the reasons for using steel are obvious. If they were, no one would even bother _trying_ anything else. Sorry, I should have said “obvious to someone skilled in the art.”:rolleyes: ---
**Author:** ![Fubaya](https://avatars.discourse-cdn.com/v4/letter/f/c2a13f/32.png) [@Fubaya](https://boards.straightdope.com/u/Fubaya)\ **Post date:** [December 14, 2008, 8:53pm UTC](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113/26 "2008-12-14T20:53:59Z")
Many Ford hoods are aluminum, I’m not sure they have any steel hoods on their trucks anymore. Infiniti G35 hoods and deck lids are aluminum, as are many Nissan cars. The BMW 6 is mostly aluminum and Jaguar and Audi make cars that are all aluminum bodied. Although there are few cars which are aluminum from the frame up, aluminum is very widely used on automobiles. (EDIT: nice list of vehicles with aluminum panels at this [link](http://www.auto-paint-meter.com/aluminum-car-chart.html)) > [@Balthisar](#): > > Obviously well-designed doors are important to intrusion avoidance during a broadside collision > … > There’s also the car’s body sides. Much of what you see from the outside looks like a body panel, but in effect it’s a huge structural element of the vehicle on its own. It keeps your roof from crushing in on a rollover; it contributes to lateral intrusion avoidance, and contributes to rigidity along all three axes of the car. The inner structures are built for safety but the outer part of doors and roofs of cars are just sheet metal skins which provide no safety. ---
**Author:** ![Balthisar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/balthisar/32/2825_2.png) [@Balthisar](https://boards.straightdope.com/u/Balthisar)\ **Post date:** [December 14, 2008, 9:31pm UTC](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113/27 "2008-12-14T21:31:14Z")
> [@Fubaya](#): > > Many Ford hoods are aluminum, I’m not sure they have any steel hoods on their trucks anymore. I’m pretty sure they’re all aluminum, and I’m thinking the Mustang hood is, too. Maybe not. It’s used mostly on higher-markup vehicles due to price. > [@](#): > > The inner structures are built for safety but the outer part of doors and roofs of cars are just sheet metal skins which provide no safety. That’s absolutely true, only the skin is integral to the assembly. There’s not really any such thing as a “body panel” as mentioned by **Huerta88** , with the exception of the front fenders (talking typical, mass market cars and common body construction techniques). So what we talk about are door assemblies, body side assemblies, and so on, which come with the outer panel permanently attached. If we really wanted to be nitty-gritty about it, there is still some contribution to crash test from the outer panels, which while not structural in nature can affect the crash dynamics. Take the hood, for example. It’s usually just held in place to the inner assembly via hemming and some sealer. What happens to a 0.60 mm panel versus a 0.75 mm panel in a 35 mpg offset crash test? Maybe nothing, but it’s definitely studied. ---
**Author:** ![Tuckerfan](https://avatars.discourse-cdn.com/v4/letter/t/eada6e/32.png) [@Tuckerfan](https://boards.straightdope.com/u/Tuckerfan)\ **Post date:** [December 15, 2008, 1:34am UTC](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113/28 "2008-12-15T01:34:50Z")
> [@Balthisar](#): > > Joining them would be an issue, as mechanic fasteners would have to be used (e.g., rivets), or a completely new resistance spot weld system would have to be developed (too conductive). Lasers or friction welding could work. One of the hold ups in wider adoption of the use of aluminum in cars with a lot of steel has to do with the cost and complexity of _rust proofing_ the car. The standard compounds used to rust proof a steel car can’t be used with aluminum components, and for various reasons, if you’re building a car with a steel body and aluminum hoods/trunklids, you don’t want to run the steel bodies through rust proofing, then fasten the hoods and trunklids on before running them through the primer process. So you have to use special compounds in your rust proofing process and keep a close idea on the mixture to prevent problems from developing. ---
**Author:** ![Balthisar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/balthisar/32/2825_2.png) [@Balthisar](https://boards.straightdope.com/u/Balthisar)\ **Post date:** [December 15, 2008, 1:47pm UTC](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113/29 "2008-12-15T13:47:12Z")
> [@Tuckerfan](#): > > Lasers or friction welding could work. Lasers are still too tricky for most body assembly operations. Currently they see the most use in roofs, either through direct lap or edge welding, or in combination with a brazing process (this latter is simply incredible; you’ve _got_ to see [for example] a Mondeo roof). VW has had limited success with using laser joining in other body in white assembly operations. But since we’re not being practical in building a car from bronze anyway, then performance and cost is nothing to worry about ;). Friction stir welding is an exciting process, and it can be an almost perfect substitution for resistance spot welding in existing facilities (process-wise). It’s chiefly being developed for aluminum applications, and I have no idea how it’d work on bronze. I’m not personally aware of any large deployment of friction stir systems in the wild; I’ve only seem them in labs to date. If they work for bronze, probably a pretty good option for building a bronze car. > [@](#): > > One of the hold ups in wider adoption of the use of aluminum in cars with a lot of steel has to do with the cost and complexity of _rust proofing_ the car. The standard compounds used to rust proof a steel car can’t be used with aluminum components, and for various reasons, if you’re building a car with a steel body and aluminum hoods/trunklids, you don’t want to run the steel bodies through rust proofing, then fasten the hoods and trunklids on before running them through the primer process. So you have to use special compounds in your rust proofing process and keep a close idea on the mixture to prevent problems from developing. Not sure what you mean here. I’m probably misunderstanding you because you generally know what you’re talking about. The only non-primer rustproofing on car sheet metal comes from the mill. Steel will be galvanized via one method or another (hot dipped, electrogalvanized, etc), or just left bare. Aluminum is rustproof naturally. The entire car body when assembled goes through a phosphate bath to remove stamping lube, magic marker marks, etc., and generally prep the car for ecoat and paint. “Ecoat” is the priming process, which provides additional rustproofing, and aluminum parts go through this, too. Ecoat isn’t the same as the primer one buys in a can; it’s an electrically charged process that ensures proper adhesion to the sheet metal parts. After this the rest of the paint process is applied prior to the body being sent to final assembly. I’m going to have to try to remember to run some copper or brass parts through an ecoat process next time I have a chance (don’t wait for an answer any time soon). I have no idea how ecoat would stick to it. On the other hand, maybe we don’t want to paint our brass car, and so it’d be irrelevant. ---
**Author:** ![Carson\_O\_Genic](https://avatars.discourse-cdn.com/v4/letter/c/cdc98d/32.png) [@Carson\_O\_Genic](https://boards.straightdope.com/u/Carson_O_Genic)\ **Post date:** [December 15, 2008, 1:54pm UTC](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113/30 "2008-12-15T13:54:35Z")
> [@Balthisar](#): > > Joining them would be an issue, as mechanic fasteners would have to be used (e.g., rivets), or a completely new resistance spot weld system would have to be developed (too conductive). Since we’re making the structures from bronze, we could fall back to silicon bronze fusion welding, although this has environmental impacts and is expensive. ``` The dinosaurs OAW and SMAW weld bronzes all day long, and GTAW works on some alloys. ``` ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [December 15, 2008, 2:52pm UTC](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113/31 "2008-12-15T14:52:33Z")
> [@Carson\_O\_Genic](#): > > The dinosaurs OAW and SMAW weld bronzes all day long, and GTAW works on some alloys. FYI, (and you might know this, but some don’t, I’m sure) SMAW is now called MIG (metal intert gas) and GTAW is called TIG (tungsten inert gas). ---
**Author:** ![Balthisar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/balthisar/32/2825_2.png) [@Balthisar](https://boards.straightdope.com/u/Balthisar)\ **Post date:** [December 15, 2008, 3:16pm UTC](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113/32 "2008-12-15T15:16:20Z")
The issue is automating those applications for assembly an entire body in white. The the purposes of building a bronze car, perhaps automation isn’t an issue, and everything can be welded by hand. If we want to mass market the bronze car, then we have to worry about maintenance costs, cost of operation, robustness of the process, additional metal finish due to weld spatter, and so on. ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [December 15, 2008, 3:41pm UTC](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113/33 "2008-12-15T15:41:37Z")
It’s heavier and softer than steel, and costs about the same. End of story. ---
**Author:** ![Carson\_O\_Genic](https://avatars.discourse-cdn.com/v4/letter/c/cdc98d/32.png) [@Carson\_O\_Genic](https://boards.straightdope.com/u/Carson_O_Genic)\ **Post date:** [December 15, 2008, 4:01pm UTC](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113/34 "2008-12-15T16:01:31Z")
> [@Q.E.D](#): > > FYI, (and you might know this, but some don’t, I’m sure) SMAW is now called MIG (metal intert gas) and GTAW is called TIG (tungsten inert gas). Guess I’m a dinosaur too. SMAW ( shielded metal arc welding) denotes “stick”-consumable with extruded, sometimes dipped, coating of various atmosphere excluding components. The rods limited in length/diameter by resistance heating. ---
**Author:** ![drachillix](https://avatars.discourse-cdn.com/v4/letter/d/48db29/32.png) [@drachillix](https://boards.straightdope.com/u/drachillix)\ **Post date:** [December 15, 2008, 4:13pm UTC](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113/35 "2008-12-15T16:13:06Z")
> [@Huerta88](#): > > And so, according to [this](http://www.youtube.com/watch?v=T6xJzAYYrX8) (well worth watching) video, were early spacesuits. (at 5:50). You do realize that video is a joke…don’t you. ---
**Author:** ![Tuckerfan](https://avatars.discourse-cdn.com/v4/letter/t/eada6e/32.png) [@Tuckerfan](https://boards.straightdope.com/u/Tuckerfan)\ **Post date:** [December 15, 2008, 4:57pm UTC](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113/36 "2008-12-15T16:57:59Z")
> [@Balthisar](#): > > Not sure what you mean here. I’m probably misunderstanding you because you generally know what you’re talking about. The only non-primer rustproofing on car sheet metal comes from the mill. Steel will be galvanized via one method or another (hot dipped, electrogalvanized, etc), or just left bare. Aluminum is rustproof naturally. IME, the phosphating proces _is_ part of rustproofing as the phospate is bonded to the metal, not only to ensure a surface for the ecoat to stick, but also to make a “hard candy shell” around the body to protect against anything that manages to get through the paint and ecoat layers. The phosphate etches the metal (which is why dealing with aluminum components is difficult) and coatings on the steel (if any) can be lost in the process. IIRC, the phosphate coating is somewhat self-healing and can cover small scratches which make it through to bare metal in some cases. ---
**Author:** ![Scumpup](https://avatars.discourse-cdn.com/v4/letter/s/ce73a5/32.png) [@Scumpup](https://boards.straightdope.com/u/Scumpup)\ **Post date:** [December 15, 2008, 5:03pm UTC](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113/37 "2008-12-15T17:03:35Z")
I have a Suzuki Aerio station wagon. Large portions of the body are plastic. ---
**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\ **Post date:** [December 15, 2008, 5:41pm UTC](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113/38 "2008-12-15T17:41:04Z")
> [@beowulff](#): > > None of which invalidates what I said. > The Corvette is a niche-market sports car. > Saturn has never been profitable. > The Fiero was a one-off. > Find me a mass-market (let’s say 75,000 units/year) car that’s currently in production that uses something other than steel for its body panels. The Saturn plastic clad cars were in production for like a decade, and they made like two million of them. Saturn has indeed made a profit, and it’s first profit year was 1993 [http://query.nytimes.com/gst/fullpage.html?res=9F0CE2DC103EF931A25755C0A965958260](http://query.nytimes.com/gst/fullpage.html?res=9F0CE2DC103EF931A25755C0A965958260) _Saturn said yesterday that it had turned the corner financially and was finally making money. The General Motors Corporation subsidiary reported it made its first profit ever in May, nearly three years after it began making small cars in Spring Hill, Tenn. Saturn did not specify the amount of profit, but said it was enough to achieve a $1,000 bonus award for each of its 8,000 employees. If the company reports profitable operations to G.M. for the full year in 1993, Saturn employees will receive a second bonus. A Saturn spokeswoman, Jennifer Graham, declined to say whether Saturn was expected to remain firmly in the black for the rest of the year now that it is starting a third production crew in Spring Hill._ ---
**Author:** ![N9IWP](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/n9iwp/32/3154_2.png) [@N9IWP](https://boards.straightdope.com/u/N9IWP)\ **Post date:** [December 15, 2008, 6:11pm UTC](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113/39 "2008-12-15T18:11:26Z")
> [@Balthisar](#): > > Friction stir welding is an exciting process, and it can be an almost perfect substitution for resistance spot welding in existing facilities (process-wise). It’s chiefly being developed for aluminum applications, and I have no idea how it’d work on bronze. I’m not personally aware of any large deployment of friction stir systems in the wild; I’ve only seem them in labs to date. Eclipse uses friction stir welding for it’s very-light jets. No clue how may they’ve made (The company is currently in bankruptcy) Brian ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [December 15, 2008, 6:11pm UTC](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113/40 "2008-12-15T18:11:32Z")
> [@DrDeth](#): > > The Saturn plastic clad cars were in production for like a decade, and they made like two million of them. > > Saturn has indeed made a profit, and it’s first profit year was 1993 > [http://query.nytimes.com/gst/fullpage.html?res=9F0CE2DC103EF931A25755C0A965958260](http://query.nytimes.com/gst/fullpage.html?res=9F0CE2DC103EF931A25755C0A965958260) > > _Saturn said yesterday that it had turned the corner financially and was finally making money. The General Motors Corporation subsidiary reported it made its first profit ever in May, nearly three years after it began making small cars in Spring Hill, Tenn. Saturn did not specify the amount of profit, but said it was enough to achieve a $1,000 bonus award for each of its 8,000 employees. If the company reports profitable operations to G.M. for the full year in 1993, Saturn employees will receive a second bonus. A Saturn spokeswoman, Jennifer Graham, declined to say whether Saturn was expected to remain firmly in the black for the rest of the year now that it is starting a third production crew in Spring Hill._ > [@](#): > > The question of Saturn’s profitability nags. The brand refuses to reveal its financial status, but it is believed it has never been profitable or only marginally so, at best, in some years. GM’s investments in Saturn – from getting it established to feeding it with new models of late – has been massive. And GM’s investment in Saturn is far from over. As it introduces new and freshened vehicles, it must immediately prepare for replacements of those to keep Saturn’s line constantly fresh. When and how much GM will receive as a return on its investment is unknown. From here: [http://www.autoobserver.com/2007/02/saturn-gms-best-defense-against-toyota.html](http://www.autoobserver.com/2007/02/saturn-gms-best-defense-against-toyota.html) > [@](#): > > There was just one hitch: GM says Saturn never made a profit. From: [GM reorganization may be end of road for Saturn](http://www.latimes.com/classified/automotive/highway1/la-fi-saturn4-2008dec04,0,1052210.story) [Previous page](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113.md?page=1) [Next page](https://boards.straightdope.com/t/could-a-car-be-made-body-panels-from-bronze/477113.md?page=3)