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Old 29th September 2014, 17:46   #46
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Default Re: Sheet Metal Thickness - Does it matter?

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Originally Posted by rahul4321 View Post
I have a Bolero. Its a lump of metal; everywhere- Hood, Chassis, even the Bumpers are made out of Iron (instead of Fibre). 3 guys regularly sit on the hood at the local Drive-in Cinema. Sure the hood metal caves in; but as soon as you get up- the hood metal 'pop's back up again.

Pure metal being just that; metal- I would prefer being in my Bolero rather than any Maruti, Korean or Japanese in the event of a frontal impact (touchwood)
Buddy, for your sake, I'm going to hope you are never in a frontal impact and if you are, it's not in the Bolero . Touchwood.

Your Bolero (and my Jeep) are 'pure metal' yes. But they don't have any safety features to speak of. They've never been crash tested and have safety standards of a time when no one even knew what 'crumple zones' are. Modern cars are designed to transmit impact / shock away from the cabin / occupants...they may 'crumple' more, but well, whose body would you rather crumple? Your own or that of your car?

My Jeep once redecorated the rear of a Tata Sumo (in itself, a tough car). I didn't even need to get any touch-up work done (take a close look at my Jeep's pictures and you'll see a very marginally crooked bull bar). A bus rammed into the rear of my stationary Jeep once and I spent less than 2K fixing it up. At the authorised workshop.

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.

Last edited by GTO : 29th September 2014 at 17:47.
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Old 29th September 2014, 17:57   #47
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Default Re: Sheet Metal Thickness - Does it matter?

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Originally Posted by CrAzY dRiVeR View Post

The point is - International cars are not getting lighter, they are getting smarter.
Yup , I know that, I was merely explaining to blacksport why excessive weight is a bad thing in a car and so just mentioned some recent efforts by manufacturers to cut down their car's kerb weight. Yeah I agree most of them use carbon fibre and other light weight but high strength materials which we are never going to see in India anytime soon.

Quote:
Originally Posted by CrAzY dRiVeR View Post
Suggest we dont conclude on this - My 'made for India' Asian/ European car car is just as safe as the international car discussion just yet - till we have conclusive data from the Indian market (be it crash tests or proper study about weight saving measures used).

Till then - those who 'feel' good with their heavily built cars can continue to do so,
while sacrificing a bit of perfomance and economy. Others who have lighter cars, but just NOT 'made for India' extra light - can enjoy their superior machines with more power, performance and mileage while knowing they are just as safe.
Yup, that is exactly what is needed. A proper safety and crash test with made in India cars.
Will be very helpful to the public if such a test is conducted and published.

Till then we can never know whether the lightly build cars are actually the work of geniuses or just a rip off which sacrifices safety for more profit to the car maker. OR whether the European cars really is a better bet for you and your family despite their shortcomings or the heavy vault like feeling of cars with heavier build is just a mere facade and is actually just an extra burden to the car instead of a blessing.

Last edited by nakul0888 : 29th September 2014 at 18:03.
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Old 29th September 2014, 19:33   #48
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Default Re: Sheet Metal Thickness - Does it matter?

Interesting discussion there! In the current age where lighter (and rigid) materials and weight-saving measures are brought in to increase efficiency the idea of heavy material corresponds to better safety may not hold good. And also, nowadays it’s a myth that Japanese/Korean cars are less safe than the European counterparts.

In my opinion, the lines of dissimilarities are getting quite blurred. On one side we have Euro manufacturers like Ford, Volvo etc. are advertising on the use of lighter yet rigid materials like boron steel, and their cars are getting lighter by every new generation models. On the other hand, we have cars like Hyundai Santa Fe scoring best-in-class safety ratings in Euro NCAP, bettering some of the illustrious European players.

Now the problem part – the above arguments hold good in the international scene. The difference is so visible in our case because we still don’t get to experience many of these innovations in the cars sold in our market. Lighter cars remain light and vice versa for the so-called heavy sheet-metal models. The newer Fiats are not as heavy as the ones sold in India (e.g.; Indian Punto Evo v/s International Punto). Similarly, the Swift sold internationally feels much better built or rather heavy than the one sold in India (it even have that so called ‘thud’ while closing the doors). One way or other, we have to settle for a compromise based on what is being offered to us, until the time when quality test ratings and figures are made mandatory for the cars/variants sold in India.
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Old 30th September 2014, 10:06   #49
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Quote:
Originally Posted by CrAzY dRiVeR View Post

+ 10.

Fully agree with you, even though I am in disagreement with the context in which you stated the above point.

Lets take the Indian context -

[*]The marketing papers for Ciaz says it used high strength steel as a weight reducing technology - fair enough. But somehow thats at odds with the pricing at which the car is expected to debut at. We know another car which used high strength boron steel and ended up quite overpriced for the market, in the same D

What context? There is no context to my statement. Its a fact, irrespective of the market. Its just how it works.

How stuff gets priced is a completely different matter. Down to marketeers and people who talk about market/product positioning. Nothing to do with engineering as such.

In general cars have been getting heavier over the last couple of decades, not lighter. Compare for instance the original VW Golf with the latest model and you will notice a several hundred kilogram difference. Some of that is due to safety, but also emissions (cat. Convertors are heavy), more fancy stuff such as power steering, electrical windows, ACs etc. Cars have also gotten bigger.

When i got my drivers license some 35 years ago the average family saloon weighted around 1000kg. These days, at least in Europe an average family soon is close to 1300kg. (E.g. Ford Focus).

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Old 30th September 2014, 11:56   #50
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Default Re: Sheet Metal Thickness - Does it matter?

Comparing the ASEAN NCAP Test Results of a 2 cars which are best specimen of this debate because one is made of thinner sheet, i.e..Honda City (SV) and one of thicker sheet material, that is the Volkswagen Vento - 1.6 Petrol; albeit both ASEAN models.

What I notice is that Honda City has scored 5 stars safety rating (15.80pts out of 16) against 4 star of VW Vento/ Polo (14.51 pts out of 16). So definitely, Honda City is superior, there should not be an iota of doubt about it. Now the question is that do we, in India, get the same Honda City?

Comparing the kerb weight of the ASEAN City & the Indian City, my common sense would say 'No'. The ASEAN City (SV Variant) which was put under test weighs 1102 Kgs, while the Indian City weighs a full 60 Kgs lesser tipping the scale at 1042 kgs. And that is taking the Manual transmission in consideration for the Indian car (since the transmission is not specified in the ASEAN NCAP result). If I take the CVT, it weighs 1065 kgs which closes the gap further. However, for the sake of being on the safer side, I will take the manual car for comparison, i.e..1042 kgs. Also, some hair cut must also be applied on the extra airbags (6) and some other equipment which the ASEAN city might be carrying. But still, I would consider that our City uses thinner metal sheet than the ASEAN city. I will not believe that the platform and the monocoque would be any different. It would simply not make any financial sense for the manufacturer.

Coming to the Volkswagen Vento. The variant tested was 1.6 Petrol. Now, why do we have to jump to a conclusion that the Vento that is sold in India is same as the one sold in ASEAN countries? So, lets check the Kerb weight of both. The ASEAN Vento/ Polo Sedan 1.6P tested by ASEAN NCAP weighs 1180 kgs. According to VW India, the kerb weight of the Vento 1.6P is 1120 kgs. Again full 60 kgs lesser. Did I see it right? Yes, I did, but that's the Trendline model. I will check for the Highline. The brochure says 1130 kgs. That is still 50 kgs lighter. Something fishy here too. So, may I say that Volkswagen too is accused of selling a skimped model in India and a false sense of security just because its door make a 'thud'? I think yes.

Plus, one important point is that since the City has scored more points than the Vento/ Fiesta or any other car put under this test ever, it has the safest monocoque and the platform.

Draw your own conclusions now. Inviting your views please.
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Old 30th September 2014, 12:16   #51
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Default Re: Sheet Metal Thickness - Does it matter?

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Originally Posted by saket77 View Post
Draw your own conclusions now. Inviting your views please.
I think you really need to do a more indepth analysis of the difference between the variant to determine where the weight difference comes from. I'm not sure what conclussion you can derive, in terms of safety, on weight alone.

What about tires, rims, brakes, emission control equipement etc. It all comes in at a certain weight.

We could also have a debate about whether car safety requirements in India need to be different from Europe to start with. To what extent are conditions of crashes comparable? What are the average speeds at which crashes occurs in Europe versus India

Has anybody ever tried to get a detailled explanation from the various manfucturers?

Jeroen
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Old 30th September 2014, 12:28   #52
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Default Re: Sheet Metal Thickness - Does it matter?

Quote:
Originally Posted by saket77 View Post
What I notice is that Honda City has scored 5 stars safety rating (15.80pts out of 16) against 4 star of VW Vento/ Polo (14.51 pts out of 16).
Small clarification, City scored 4 stars with 2 airbags and 5 stars with 6 airbags. Vento's 4 stars are with 4 airbags.

ps: Not intended to draw any conclusions, just clarifying.
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Old 30th September 2014, 12:34   #53
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Default Re: Sheet Metal Thickness - Does it matter?

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Originally Posted by Jeroen View Post
I think you really need to do a more indepth analysis of the difference between the variant to determine where the weight difference comes from. I'm not sure what conclusion you can derive, in terms of safety, on weight alone.
What about tires, rims, brakes, emission control equipment etc. It all comes in at a certain weight.
Yes, that is a very crude analysis. As this thread is on sheet metal thickness and I presume that its on the impact of safety, then it is very common here in India to refute Japanese cars as 'unsafe' because they are made of thinner sheet metals as compared to their European counterparts.

Quote:
Originally Posted by Jeroen View Post
We could also have a debate about whether car safety requirements in India need to be different from Europe to start with. To what extent are conditions of crashes comparable? What are the average speeds at which crashes occurs in Europe versus India
Very apt. Europe's standard of safety is certainly among the best and probably even the best. And a car that holds good in those tests will certainly hold good in crashes everywhere. The conditions of crashes may not be the same but still I would go on to say that a safe car will be preferable anyday, anywhere.


Quote:
Originally Posted by blacksport View Post
Small clarification, City scored 4 stars with 2 airbags and 5 stars with 6 airbags. Vento's 4 stars are with 4 airbags.

ps: Not intended to draw any conclusions, just clarifying.
The reason for 1 star penalty - The City does not have Passenger Seat Belt Reminder. Not because of additional Airbags.

Last edited by saket77 : 30th September 2014 at 12:35.
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Old 30th September 2014, 12:49   #54
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Default Re: Sheet Metal Thickness - Does it matter?

Well, I can vouch for the higher levels of safety on the German cars like Rapid, Vento and others by personal experience.

The capital was hit by a massive sand storm on the 30th of May, 2014.(Coverage: Massive storm in Delhi NCR: More: 250 trees uprooted)

My Skoda Rapid was parked in the court complex at the High Court of Delhi. My dad had unwittingly parked the car under a a huge tree and was working in his office. That is when the storm struck. After the storm had passed by, the parking attendant came rushing to dad and informed him that a huge branch had fallen on the car.
The branch was duly removed and the damage was noted. It was a shattered windshield and a small dent on the front left A-Pillar apart from a few scratches on the front left door. Now, to give you an idea about the actual size of the branch, consider this - It took all of 6 people to just get it off the car including three CISF jawans, two parking attendents and my dad. Onlookers said that the branch had fallen from as high up as approximately the fourth level of the building next to it.

I will try to find pictures of the accident but I believe I had them in my previous phone only.

[OT:] I have to remark that the Skoda A.S.S. was pretty amazing. The car was taken away and within two days, the damage had been taken care of with the utmost care. The bill was surprisingly low at just around Rs.9700. This included a new front windscreen, sealer kit, removal of the dent and complete repainting of the front left door and labor charges. In contrast, a friend of mine had to get his Hyundai Verna's cracked windshield repaired. The part alone set him back by over Rs. 10k.
Loving the Skoda experience.

Cheers!

Last edited by Batfreak : 30th September 2014 at 12:51.
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Old 30th September 2014, 12:51   #55
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Default Re: Sheet Metal Thickness - Does it matter?

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Originally Posted by saket77 View Post
The reason for 1 star penalty - The City does not have Passenger Seat Belt Reminder. Not because of additional Airbags.
OK, but did the 6 airbag version have seat belt reminder?

BTW, I glanced through most of the cars that has been tested there - available in India, of course - and I see that except 2013 Fiesta and the 2014 City, none of the cars have scored 5 stars. Maybe I am wrong, but perhaps comparing Fiesta with the City might not have suited your arguments very much. The Polo/vento is half a decade old when compared to the 2014 City.
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Old 30th September 2014, 13:02   #56
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Default Re: Sheet Metal Thickness - Does it matter?

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Originally Posted by GTO View Post
Buddy, for your sake, I'm going to hope you are never in a frontal impact and if you are, it's not in the Bolero . Touchwood.


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.
Now I am scared! Heh Heh. I always thought that lump of metal will protect me from everything and the airbags etc will not even need to come into the picture- but now I am not so sure.

Hmmm, maybe its time to convert it into a full fledged off-road vehicle and buy that new Scorpio

Thanks for the heads up GTO.
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Old 30th September 2014, 13:06   #57
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Default Re: Sheet Metal Thickness - Does it matter?

Quote:
Originally Posted by blacksport View Post
OK, but did the 6 airbag version have seat belt reminder?
Yes.

Quote:
Originally Posted by blacksport View Post
BTW, I glanced through most of the cars that has been tested there - available in India, of course - and I see that except 2013 Fiesta and the 2014 City, none of the cars have scored 5 stars. Maybe I am wrong, but perhaps comparing Fiesta with the City might not have suited your arguments very much. The Polo/vento is half a decade old when compared to the 2014 City.
Sorry, but I did not looked at the Fiesta report at all. I will look into it. [EDIT: The Ford India website does not specify the kerb weight/gross weight of the Fiesta. So, without the official figures, the comparison cannot be made]

About the Polo or Vento being older, the test reports state that they are 2013 Polo/ Vento. Also, older cars based on older platforms being sold by manufacturer should not be the excuse: A point that you will yourself agree to.

Another point that I will like to make to keep the discussion fair & in the right spirit is that the Vento might have scored 5 stars too in the test, but unlike ASEAN City (6airbag variant), it lacks ESC & Passenger seatbelt reminder. Thus, it had to pay the 1-point penalty too. Just like the 2 seatbag variant of the ASEAN City which lacks the passenger seat belt reminder. The goodness of the City here is that despite discounting these facts, the total score was higher.

Also, another point in case - If one gives good regard to the NCAP, then let us hear what the masters themselves have to say on the sheet metal theory. Here is an excerpt from the Australian NCAP FAQ's article followed by the link:

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.
Link:http://www.ancap.com.au/faqs

I think this should bring down all speculation on the thread to rest.

Regards,
Saket

Last edited by saket77 : 30th September 2014 at 13:22.
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Old 30th September 2014, 13:42   #58
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Default Re: Sheet Metal Thickness - Does it matter?

Quote:
Originally Posted by saket77 View Post
Draw your own conclusions now. Inviting your views please.
Since you look really excited about the 5star rating of the city compared to the 4star of the Vento, which of these look safer to you?

Honda City 2014 -

Good protection to chest. Light, but not critical impact to chest. All good down below.

AOP points total - 15.58
Lost out 1 star due to absence of ESC and SBR. India doesnt get ESC either.

VW Polo 2014 -

Good protection to head and chest. Light but not critical impact to legs.

AOP points total - 14.51
ESC not available on the variant tested. Available in India in the TSi trim.


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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.

Last edited by CrAzY dRiVeR : 30th September 2014 at 13:47.
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Old 30th September 2014, 13:54   #59
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Default Re: Sheet Metal Thickness - Does it matter?

Quote:
Originally Posted by CrAzY dRiVeR View Post
Since you look really excited about the 5star rating of the city compared to the 4star of the Vento, which of these look safer to you?
Please note that Yellow means adequate. The excitement is justified. Apart from yellow & green on the charts, please give due importance to the overall test score and the final star rating.

Quote:
Originally Posted by CrAzY dRiVeR View Post
AOP points total - 15.58
Lost out 1 star due to absence of ESC and SBR. India doesnt get ESC either.
Correction: ESC is present in the ASEAN City- Both variants tested.

Quote:
Originally Posted by CrAzY dRiVeR View Post

VW Polo 2014 -

AOP points total - 14.51
ESC not available on the variant tested. Available in India in the TSi trim.
Available on only the TSI-DSG variant. However, not at all relevant when you are comparing the crash worthiness and sheet metal.

Regards,
Saket

Last edited by saket77 : 30th September 2014 at 13:56.
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Old 30th September 2014, 14:00   #60
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Default Re: Sheet Metal Thickness - Does it matter?

Let's just hope none of the efficient Jap manufacturers are reading this thread.

Next thing we know, they might start optional lead bricks to be inserted into the door panels to make the doors thud.

I believe it's the crumple zones that make a car safe and not the thickness of the sheet metal used. Anyways it is the chassis that will take the most, in serious crashes, the sheets will not add any good.
Why would someone want to spend repairing their own body instead of a car in case of accidents.
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