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Old 30th September 2014, 14:06   #61
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Default Re: Sheet metal Thickness- Is it a big deal?

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Originally Posted by CrAzY dRiVeR View Post
Maintaining the showroom looks is anything but cheap. One detailing session costs as much as a regular service for the Japanese brands. Forget repainting costs which are just too prohibitive. Of course, not everyone will panic because of a single dent.

Depends on priorities. Life is more than just kmpl. A decent mix of both is what I would look at!
+1.

Also, in typical urban scenario where parking space is at a premium and we end up parking in streets where kids play cricket and every now and then a ball comes flying and kisses the sheet metal and leaves few kiss-marks, we may realize that that "something extra" (read thickness of the metal) may be a boon rather than a bane.
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Old 30th September 2014, 14:08   #62
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Default Re: Sheet Metal Thickness - Does it matter?

I would say for our roads we need the mix of both. Modern car with crumple zone and little heavy car. Cars like punto or polo are better on both cases. Yes we lose little performance on punto comparing to swift but any day i would go with punto and reason is simple its modern and also heavier. It would handle both frontal impact on highways and also the day to day dents from heavy traffic.

Ambassador, Bolero - Thick metal and heavier. good for day to day traffic but not for frontal impact.
Amaze, Etios, Swift - Thin metal and lighter. Maybe better in frontal impact but even a kiss from moped will burn your pockets.
Punto, Polo, Linea - Thick metal, heavier, crumple zone. Better in both frontal impact and day to day dents.

Last edited by klassics45 : 30th September 2014 at 14:14.
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Old 30th September 2014, 14:08   #63
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Default Re: Sheet Metal Thickness - Does it matter?

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But in any frontal impact over 50 kph, the last car I'd want to be in is my Jeep. It won't break, but it will surely, definitely & certainly break me.
"Your Chassis" would surely be a mess if you were in that Jeep.

What the Japanese (Could add Korean too) have achieved is incredible. You are as safe in a Japanese car compared to European. Yes; a Japanese car may have a lot visible damage. Insurance can take care of that. It is about how well a car company designs the shell as that is what protects you. Who cares if the car is a wreck. In the end, you want to get out alive or with the least possible injury. Though I would like to believe thicker sheet metal is a better bet, I don't think this applies anymore. Modern design and material have changed the game.

I remember this being a very important topic of discussion when we got our first Suzuki 800. People said the car is a tin can. You would sometimes find a case of a Amby rammed into a Suzuki and the Jap is total lost. What you don't know is if the Amby's steering wheel went through the rib cage of the driver and killed him in an instant. So much for sheet metal thickness.

Among the Europeans, Fiat's have the best "vault" effect. Shutting the door or the boot lid on a Linea is enough to give you a sense of feeling safe. I don't find the same feel in VW's or Ford's. What this "vault" feel also does is ruin the performance of the car. It is not about 0-100-0 figures alone. It includes in gear performance and fuel economy. Fiat's are the worst and they just keep getting heavier. Negatives aside with regard to excess weight on Fiat's, I feel some of this excess weight combined with the well designed suspension and chassis results in the most "flat" ride in the segment and beating some above it.

Efficiency is the name of the game. I want my car to be fast, safe, efficient and for now the Japanese rule.

Last edited by sandeepmohan : 30th September 2014 at 14:17.
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Old 30th September 2014, 14:09   #64
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Default Re: Sheet Metal Thickness - Does it matter?

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Originally Posted by CrAzY dRiVeR View Post
NCAP tests the crash at 60 kph. What say - at 80 kph, City will become red on the chest area, while Vento will become red on the legs. Which would be safer then? Inviting your views.
Test it at 200 kmph and all turn red. That is no point discussing.

Please look at the data at hand which is available. If 'estimating' how safe cars are is so simple as you did, then why did the City got higher points than the Vento. Or is that that you refute the test results?

Please look at what I quoted straight from the Australian NCAP which says about sheet metal thickness and think about if we are buying a skimped version of European cars like Vento too in India. Its not a City vs Vento war. It was an example of how thin sheet cars can be safer.

And also please note that that the Vento has been given some modifiers too, which the City wasn't. That is visible in the very pictures that you posted.

Regards,
Saket
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Old 30th September 2014, 14:09   #65
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Default Re: Sheet Metal Thickness - Does it matter?

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Apart from yellow & green on the charts, please give due importance to the overall test score and the final star rating.
Sorry, Please explain why the yellow and greens have to be ignored?

They represent the area of impact and are just as important as the quantity of impact. The overall scores and final star rating shows the overall quantity of impact at a speed of 60 kph. It is clear that the Vento is green on the important areas at 60kph, while the City is just about adequate.

My question is simple - what about 80 kph?

More speeds - more likely for the yellows to become reds. Honda City will have more impact on the chest area, while Vento will have more impact on the legs. Now which one is more life threatening?

EDIT: Just read your comment about 200 kph. Funny, but can we please get on with more serious discussions? I'm not refuting the data, I'm on interpreting it with all the data rather than just the overall figure.

Last edited by CrAzY dRiVeR : 30th September 2014 at 14:15.
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Old 30th September 2014, 14:18   #66
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Default Re: Sheet Metal Thickness - Does it matter?

By the looks of it, you seem to out rightly refute the NCAP results too. I do not think that anyone among us is qualified enough to do so.

Quote:
Originally Posted by CrAzY dRiVeR View Post
Sorry, Please explain why the yellow and greens have to be ignored?
And why do you think 15.8 to be lower than 14.5. And again 5 stars to be less than 4.

Quote:
Originally Posted by CrAzY dRiVeR View Post
They represent the area of impact and are just as important as the quantity of impact. The overall scores and final star rating shows the overall quantity of impact at a speed of 60 kph. It is clear that the Vento is green on the important areas at 60kph, while the City is just about adequate.

My question is simple - what about 80 kph?

More speeds - more likely for the yellows to become reds. Honda City will have more impact on the chest area, while Vento will have more impact on the legs. Now which one is more life threatening?
Sorry, but no assumptions. Let the test prove that. If you are interested in my assumption, then the test score of Vento will be 13 & City will be 14.2.

Quote:
Originally Posted by CrAzY dRiVeR View Post
EDIT: Just read your comment about 200 kph. Funny, but can we please get on with more serious discussions?
Yes please. According to your comment, at 80, green will only turn yellow. Then at 120, yellow will turn orange (marginal). By 180, it may still only be brown (weak), but not poor. And any inputs on modifiers on Vento?

Last edited by saket77 : 30th September 2014 at 14:22.
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Old 30th September 2014, 14:36   #67
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Default Re: Sheet Metal Thickness - Does it matter?

Only replying to the relevant parts -

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Originally Posted by saket77 View Post
And why do you think 15.8 to be lower than 14.5. And again 5 stars to be less than 4.
15.8 is higher than 14.5 no doubt.

That 15.8 means Honda city did a better job of transmitting less pressure into the cabin. Brilliant indeed. VW transferred more pressure on the legs. More pressure than the City overall. Full credit to the city for that.

What that 15.8 also means - the city transmitted some pressure to the Chest. You can keep repeating that I'm refuting NCAP data, but the fact is - I'm only qouting NCAP data. They themselves gave the graph that clearly shows yellow for the chest for the City.

Quote:
Originally Posted by saket77 View Post
Sorry, but no assumptions. Let the test prove that.
Exactly. There are no assumptions here. The chart is available right on your fingertips, courtesy ASEAN NCAP.

Quote:
Originally Posted by saket77 View Post
Yes please. According to your comment, at 80, green will only turn yellow. Then at 120, yellow will turn orange (marginal). By 180, it may still only be brown (weak), but not poor. And any inputs on modifiers on Vento?
First of all - 80 kph is still well within the legal limits. Plus, a deviation of 20 kmph from the test results wont have drastic change in the data. As i told earlier, lets get on with serious discussions.

Secondly - On the modifiers -

Its not like the car is given a modification to pass the test. Modifiers only mean that the rating of 'yellow' given for the leg region for the vento is a modified value. Reason most probably - is to account for the deformation of the plastics of the dashboard.

When modifiers are used, the actual results from the test will be reduced when they publish it. This is more or less like a 'margin for error' scientists do when publishing test results.

Last edited by CrAzY dRiVeR : 30th September 2014 at 14:39.
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Old 30th September 2014, 14:45   #68
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Default Re: Sheet Metal Thickness - Does it matter?

Heavier metal necessarily doesnot mean more safe. If that was the case, The old Mahindra Jeep, or a Tata lorry should have been the safest.

I remember an old comparison when Maruti 800 and Omni was launched. People called it ultralight and highly unsafe when compared to Jeep, Amby or Fiat. But the facts revealed that the Mauthi's were far more safer in case of accidents when compared to Amby,Fiat.
And yes, the 700 odd kilo F1 cars should have been the least safest car in the world given their speed,which is not the case.

Of course thicker metal adds to safety but equally important to have advanced design,aerodynamics,safety kits etc.

Things where thicker sheet felt better are:
1. The feel of owning a solidly built car.
2. Avoids frequent dents. Our Innova has lot more dents when compared to Vento or Ecosport.
3. If a car is not aerodynamic and has lighter sheet, is less stable on high speed compared to a car which has thicker sheet and equally aerodynamic.


Downsides of thicker sheet:
1. Definitely slower. The same car with thinner sheet shall go faster. After all its physics.
2. One needs more effort in opening/closing the doors!.
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Old 30th September 2014, 15:23   #69
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Default Re: Sheet Metal Thickness - Does it matter?

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Originally Posted by PrideRed View Post

Things where thicker sheet felt better are:
1. The feel of owning a solidly built car.
2. Avoids frequent dents. Our Innova has lot more dents when compared to Vento or Ecosport.
3. If a car is not aerodynamic and has lighter sheet, is less stable on high speed compared to a car which has thicker sheet and equally aerodynamic.


Downsides of thicker sheet:
1. Definitely slower. The same car with thinner sheet shall go faster. After all its physics.
2. One needs more effort in opening/closing the doors!.
couple of thoughts/comments: Aerodynamics have nothing to do with the thickness as such. As long as the correct shape is maintained the Aerodynamics outcome is a given.

Thicker is slower? Well, yes in theory, but I'm not sure how much difference it really makes. Couple of tens of kg isn't going to make a whole lot of difference on most cars, unless really underpowered.

the effort required to close or open a door, is more a design issue than anything else. Properly designed door and subsequent hinges, properly maintained and you would never know how heavy (or light for that matter) the actual door is.

The nice sort of clunk type of sound we associate with heavy doors, is most likely more due to rigidity designed into the door, the appropiate above mentioned door hinges and really good locks, and door stoppers/guides then the weight perse.

Jeroen
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Old 30th September 2014, 15:34   #70
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Default Re: Sheet Metal Thickness - Does it matter?

Dear Crazy Driver,

Totally understand the concept of modifiers in the test. Of course, I never meant that the car was modified in some way to pass the test. Apologies if I sounded so, inadvertently.
Also, the thread was not about the Vento Vs. City. It was about Thinner vs. Thicker skin. I just wanted to convey that external body panels do not play any significant role in the car's performance in the crash. Also, another food for thought from the data which I gave in my comparison report of Vento & City should make us think if we are indeed buying the same Vento here as in other countries. Indeed, it is not the same City we buy here, but again, not the same Vento too. And that was an eye opener for me, if not for someone else.

If the thread title is the only thing to summarize, then forgetting the ventos & the citys and the fiestas, all I can say that everything else remaining the same, the thinner or thicker sheet panels DO NOT MATTER for crash safety. I have already quoted my source which is the NCAP itself. Quoting it again to finish my argument:

Quote:
Q:Is the metal body thickness of any car a factor considered in crash testing and does the thickness have any influence on the results of a crash?

A: Modern car designs have a very strong passenger compartment combined with structures that are deigned to crush in a controlled manner. Exterior body panels have very little influence on these structures.
(Source: Australian NCAP; http://www.ancap.com.au/faqs)

Thanks,
Saket

Last edited by saket77 : 30th September 2014 at 15:40.
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Old 30th September 2014, 15:42   #71
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Default Re: Sheet Metal Thickness - Does it matter?

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Originally Posted by Jeroen View Post
couple of thoughts/comments: Aerodynamics have nothing to do with the thickness as such. As long as the correct shape is maintained the Aerodynamics outcome is a given.

Thicker is slower? Well, yes in theory, but I'm not sure how much difference it really makes. Couple of tens of kg isn't going to make a whole lot of difference on most cars, unless really underpowered.

the effort required to close or open a door, is more a design issue than anything else. Properly designed door and subsequent hinges, properly maintained and you would never know how heavy (or light for that matter) the actual door is.

The nice sort of clunk type of sound we associate with heavy doors, is most likely more due to rigidity designed into the door, the appropiate above mentioned door hinges and really good locks, and door stoppers/guides then the weight perse.

Jeroen
Well i did not mean in anyway aerodynamics has anything to do with sheet metal thickness. All i meant was if a car is not aerodynamic and has thinner sheets,would be a nightmare to drive at high speed. The same car with thicker sheets would not get much impacted by wind and better to drive at high speed.

Design of door definitely has impact on usability but same design door is definitely easier to operate if made of thinner metal sheet.

Thicker sheet means more weight. This means the car is bound to be slower,lesser FE. Now to measure by how much depends on how much weight one is going to chop.
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Old 30th September 2014, 16:06   #72
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Default Re: Sheet Metal Thickness - Does it matter?

I think its easy to discuss this if we all agree to the Automobile axiom that says "No car is perfect"

Yes, i feel super safe in a FIAT - factors contributing to that are many and include the 'thud' sound. But more important of those is the fact that they have a wonderfully tuned suspension setup, they know how to throw up that extra weight and in which direction during braking and during cornering. Another important factor is the superbly calibrated hydraulic steering. And yes it has got a good structure with proper crumple zones. There is no safety side compromise due to its added weight, only performance compromise that can be fixed with numerous after market solutions.

Moving to a hyundai which has a 5-star safety rating - i am just sh*t scared - factors contributing are many including the absence of the 'thud' sound. But more important factors are the ill tuned suspension and the touch-me-not kind of steering at high speeds. And yes it has got a good structure with proper crumple zones. There are a few safety compromises due to its ill tuned suspension and steering, but yeah it can be fixed too, only at the manufacturer though, if he acknowledges there is a problem in the first place.

Now consider those important factors mentioned above and adding a requirement that i need a safe car on the highways, i would blindly pick the former despite its lesser efficiency and performance.

I believe the sheet metal thickness is the most trivial of differences and is only used as a punching bag excuse by semi-auto-literates on both sides to beat each other. We have examples of heavy cars in Mahindra quanto with pathetic driving dynamics and light cars in alto k10 with pathetic safety structure.

Yes European cars need to lose weight, but at more important places than their sheet metal and not at the cost of messing up its driving dynamics. You wouldn't blame the batting collapse on your no.11 batsmen would you? But in the absence of a non-performing top-order you want your no. 11 to put in his best. In the absence of proper driving dynamics i would want my Hyundai to atleast provide me with a thicker sheet metal to protect me from those low speed impacts and dents. It costs nothing more than a fraction of a sec and a fraction of a kmpl. I can see the Europeans already addressing their side of the problems as pointed by the OP, but i don't see the Asians addressing their issues anywhere.

We would be fools to believe sheet metal thickness is the only thing that makes Europeans better and we would also be fools to believe that its the only thing holding back the European cars from mind boggling performance numbers.

Lets talk about more real and important issues ok? Not petty things like sheet metal thickness or length of our .....

PS: I can get my European diesel tuned to make it a meaner machine, but please point me to some after market guy that can fix the Hyundai's steering and suspension, will you?
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Old 30th September 2014, 16:09   #73
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Default Re: Sheet Metal Thickness - Does it matter?

Having driven the City for 4K kms now, could say that initially i had the same mindset about this being light build car. Of that 4k kms almost 75% are covered in highways. Though have never driven past 120km speed, i could feel that it does not felt so bad or filmsy when overtaking/when heavy vehicles drive past me around 100 km speed. That was a bit of sweet surprise, as i had envisaged even poorer dynamics owing to lighter build.
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Old 30th September 2014, 16:10   #74
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Default Re: Sheet Metal Thickness - Does it matter?

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Well i did not mean in anyway aerodynamics has anything to do with sheet metal thickness. All i meant was if a car is not aerodynamic and has thinner sheets,would be a nightmare to drive at high speed. The same car with thicker sheets would not get much impacted by wind and better to drive at high speed.
There are several such cars running on our roads like the WagonR, Santro, i10, etc which have the aerodynamics of a brick.

Surely lighter cars are affected more by cross winds too. Also, heavier cars, in a sense are safer in crashes too, along with giving you a planted feel on the road while traveling.
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Old 30th September 2014, 16:34   #75
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Default Re: Sheet Metal Thickness - Does it matter?

Instead of discussing engineering aspects of sheet metal thickness with respect to the safety, this thread is becoming fight between European cars vs Japanese/Korean cars. Why not compare only Wrangler and Thar if this is what the thread is all about?
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