What are the pros and cons of plastic cars?

In order to reasonably discuss this topic, we must first know something about the subject. 'Plastic' is no longer limited to describing the model cars many of us 'boomers made as kids. In fact, using just the term 'plastic' prohibits any real argument because there are now literally 100(0?)'s of compounds that can fall into that broad category. Soooo, let's move on to a topic that is relevant...such as whether ANY type of 'plastic' has a longterm ROI that is more favorable than ANY metals.

Here's my 2 cents worth. I scratched the side of my "plastic" fender as I was backing out of my parking space. Small scratches, BUT the price tag to fix it, $1595.00. Had I had steel bumpers, the price would have amounted to a big fat $0.00

Danny

My husband sideswiped a car and there wasn't that much damage to his car and being as the vehicle had only 60,000 miles I felt sure the Ins company would authorize repair. No such thing. The vehicle not metal but plastic so they totaled it. It was a huge loss to us.
Thank you. jg

Pros: Plastic cars should be lighter, cheaper and improve the
Chances for electric cars to advance. They should hold up
I have driven the same car with plastic body for 43 years.

Cons: Without a steel frame they will be even more dangerous in
accidents involving the increasing number of huge pickup
Trucks on the road today.

My 1955 Buick Roadmaster (all 5500 lbs. of it) T-Boned. I don't think the Para-medics could help at all.

Yes I'd buy a plastic bodied car again and again and again.
2003 Corvette Convertible Owner.
mrgil

We all know what plastic hitting plastic is like. The way I see it the more people driving plastic cars makes it even safer. In addition, I recently bought a Toyota Prius (Hybrid) and although it is made of plastic and is small Toyota has superior crash protecting technology built around this vehicle. Toyota puts a steel "cage" if you will around the engine for protection along with surrounding airbags. The impressive part of this technology is that there are two grades of steel- a softer steel for the initial impact in a crash which serves as more of a cushion until you finally reach, if the crash is bad enough, the strongest form of steel which finally protects the passengers from impact. This car and many of Toyota's have buckle points on the steel to help facilitate the appropriate bending of the steel at the right time of the impact. And for a small car it is very spacious. My husband is 6'2 275# and he drives the Prius. He traded in his Lexus LX470 SUV for it and he is very happy he did! We might as well get used to the idea, it is the way of the future, embrace it!

AREN'T WE SUPPOSED TO BE FINDING A BETTER SOLUTION TO OIL DEPENDENCY?

NOT THIS WAY...

I live in Canada where they put salt on the roads to melt the snow and ice in the winter. The resulting slush eats metal car bodies and frames to the extent that corrosion not wear was always the factor that prompted me to trade in or purchase a replacement vehicle. I purchased a used 1996 Saturn SL1 in 1999 and I am driving it to this day. Further more it looks amazing despite being parked on the street year round with no special care. Too bad Saturn is turning away from plastic bodies. When the time comes to replace my SL1, I will be looking for a vehicle with as much plastic in the body as is practical.

At a time when there is so much debate regarding the state of our world and the American economy I'm surprised at the tone of rdicule towards plastics. I drive a Saturn SL1 and a Vue both of which are essentially plastic cars with a steel cage. They are fuel efficient and have an extremely good safety record. I even witnessed a Saturn SL2 get hit (T-Boned) by a Suburban (1971 as it turned out) and the Saturn driver got out and walked away basically unharmed except for a mild concussion. The suburban hit the saturn doing 35 mph. I know how fast because I almost hit her as well (she ran a red light). My point is that plastics are not new. Now here is the kicker. No more Saturns will be made this way since GM took them over and has begun it's big brother machinations. GM has stated that it is too expensive to produce and like their very efficient electric car they are stopping production of traditional Saturns and are re-tooling the plants to be like all GM cars, supposedly more cost effective. I don't even begin to believe that. This year (2007) is the last year of a traditional Saturn body. Plastics aren't new, they are effective, and they are environmentally friendly as much as steel could ever be. Ultimately it isn't about the plastics in reality it is about the jobs and the "cost effectiveness" of plastics that will win the "Capital Market". That will never change.

Having a steel body is not critical at all for vehicular safety. Indy and Formula 1 cars often hit the wall and shred at 190MPH, with their carbon-fiber composite shells getting destroyed, but the steel tubular cage and seatbelts inside staying intact and allowing the drivers to walk away from those accidents.

Putting together a strong structure under light, non-structural body panels can substantially reduce vehicle weight. This means that a smaller engine (or smaller electric motors) can run the vehicle, putting more of the energy into moving the passengers (the whole point of the vehicle in the first place) and less into moving the vehicle itself. Amory Lovins from the Rocky Mountain Institute has written a lot about this...it's a good read.

The carbon fiber used in race cars is still a little pricey for high-volume cars, but plastics - particularly biodegradable soy-based plastics, make a lot of sense. Plus, the plastics could have the color go all the way through, enabling scratches and scuffs to be sanded and buffed out without requiring a repaint...and the plastics can be melted down and re-formed for a much better recycling process, eliminating further waste.

No doubt about it. One word, my friend..."Plastics"

As a firefighter, we have enough problems getting people out of a wrecked car. If this plastic gets into a mangled mess, yes it may be easier to get them out, but what is the compartment space going to look like? Will it really withstand extreme heat if it catches fire? Plastic burns and melts at a lot lower temperature than aluminum. A trapped occupant will have less time to escape a burning vehicle and we will be recovering a body enclosed in melted plastic. Am I for plastic vehicles? Not really. Leave the plastic vehicles to toys and golf carts.

I used to own a Pontiac Fiero. With the exception of parts-bin mechanicals, I thought the plastic panels on steel frame was a good idea. Although there was considerable cowl shake and the body noises seem to be louder than hoped, the car was fun to drive. In time, these annoyances could have been eliminated. This design could be an idea for a future sports car like a Corvair by using better suspension and mechanicals from the Suburu WRX/STI.

The only pro is cosmetic. The con is as long as the nothern states continue to use salt in the winter the main steel framework rusts out under the plastic. This goes unseen until ssftey is compromised.

I have a degree in plastics engineering and work specifically with plastic materials, composites, and laminates for automotive application so I not only have a strong background in this subject, my knowledge and work experience relate directly to this issue.

As I read through these opinions, I can't help but wonder where most of the respondents have been living for the past 50 years. There are more plastic parts in cars, protecting the passengers, than ever and amazingly enough they are safer for it. The fact of the matter is that plastic materials are what protect the passengers. The steel body bleeds energy out of a collision event but with proper design, composite materials do the same thing much more effectively. Presently, costs are simply too high to implement the technology in a way that produces appropriate economies of scale - material costs are too high and manufacturing processes too slow (also driving up cost). That's why you only see this technology in supercars with price tags in the $200K+ territory (the Ford GT is an exception).

We've been driving composite paneled cars for nearly 60 years and moving to a composite vehicle would be the natural progression. There are plastics available that are stronger and more resiliant than any steel used in vehicles (either High Strength Steel - used in panels, or Ultra High Strength Steel - used in structures and door intrusion beams). One person stated that not all plastic materials can be recycled. While true for most thermosets, that is a completely false statement for thermoplastics. Nearly all plastic content in automotive applications must be recyclable by law. The exceptions are thermosets (mostly in electrical applications for their non-conductive nature or high heat applications). And while most plastics are petroleum based, many are being formulated using biotech so they are green-friendly. This is gaining a lot of traction in the automotive world because the costs are lower, it is a great marketing tool, and the materials are of high quality.

My suggestion to anyone who thinks plastic cars are a bad idea is to do your research before jumping to conclusions. The technology exists to make 90% of an extremely safe car out of plastic, engine and all. The only reason it hasn't been done is because of public perception. I'm a huge fan of steel cars but the next wave is coming. Provided costs balance out, the right plastic in an application is better than steel any day.

Remember: there is no such thing as a bad plastic part, just bad designs and bad material selections.