Built to Last??

To all,
Someone suggested in an earlier thread that the modern automobile is
vastly superior to those of earlier generations.
Do modern automobile's really last longer and take more abuse than
those of earlier generations?
Is the complexity/reliability of newer automobiles worth sacrificing
the simplicity of repair and part replacement of an older
automobiles??
Can something simply be "over-engineered"?
And finally, are things today "built to last" like they were say 100
years ago?
I'd like to get an Engineer's perspective.
-Steve
Reply to
Steven Mason
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No points to adjust. Plugs last 100k miles at least. Really no such thing as a tuneup ever needed. Self- diagnostics.
Connectors are still an Achilles heel, and getting more so as signals get weaker.
And those high performance plastics will degrade to dust.
Today's cars are much better than those of one, two, three generations ago. But they won't be restorable in one or two generations, so enjoy them now.
-Mike-
Reply to
Mike Halloran
Oh..how soon we forget! Automobiles were never intended to last long! I read (or heard) that Mr. H. Ford considered giving away model "T"s and live off the replacement parts at a hefty profit margin - secondary producers would be kept out by patent protection or forced out by changing the parts year by year - so it would be harder to hit a moving target (sound familiar - OPERATING SYSTEMS?)
Corrosion science (beyound painting)was not used consistently until the early 1970's - cathodic protection in the form of galvanization is common today.
Electronics in automobilies built within the past 20 years is the real "quality enhancement" - mechnical carburators cannot achieve the required engine control that electronic can do for the common auto.
Ed
Reply to
Edward D. Vojcak
"Built to last" ? by itself this is highly subjective. As an engineer, I would certainly say that everything designed is built to last. But, the real question is: how long?. Engineering at an earlier time was done with less sophisticated analysis tools available. The tendency was to design with a large safety factor to account for the great unknowns that went into a design. In this way, many items had a very long life ? or they were built to last forever. Today, we are blessed (or cursed) with a high level of sophistication of analytical tools. With a high level of confidence, we can determine stress, strain, fatigue, etc. in complex parts. With a high level of confidence, we have very detailed statistics of the life of components. Now, you have to realize that companies are run (for better or worse) by bean counters. These bean counters also have highly sophisticated analytical tools that determines profitability given all sorts of variables, including component life. The bean counters know that on a given widget, they can save 1 cent, for example, on material if it is redesigned with a slightly shorter life. Applied over millions of parts, this 1 cent adds up to a nice bonus in their pockets. In addition, with a finite life designed into parts, you ensure repeat business.
So in conclusion, things are still built to last. However, how long they are built to last is now highly controlled. Take for example your timing belt in your car. Most need to be replaced at a factory recommended 60,000 to 90,000 miles. You almost never experience a failure of the timing belt BEFORE the factory recommended interval. However, failures shoot up dramatically the further BEYOND the factory recommended interval.
Reply to
Steve S
I do not believe I am exagerating when I say built to last means "on average" a 5 year life. There is no money to be made in after market sales if things are built to last 20 years. This can only be acheived with a a vigorous maintenance regime.
Reply to
Alan O'Neill
In addition, people tend to see things that are old as needing replaced especially something that has significant style changes every couple of years that can date it.
Sincerely,
Donald L. Phillips, Jr., P.E. Worthington Engineering, Inc. 145 Greenglade Avenue Worthington, OH 43085-2264
snipped-for-privacy@worthingtonNSengineering.com (remove NS to use the address) 614.937.0463 voice 208.975.1011 fax
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Reply to
Don Phillips
Suppose I wanted to rebuild a car to last. What would be a good car to start with, something with a real frame, and what would be the best stuff to use, axle drive train etc. The goal would be to have a car that could be maintained myself and would be a general driver car. Assume I would have a fair homeshop and average metal working skills. I would want a mininum or no of specility "dealer only" parts. After it was done I would not want to continually work on it.
What would have to be redesigned because the "best" for cheap manufacture is not the best for maintainence. I'm thinking about things like the double flare brake lines. Good the first time you assemble it and it last but once you have to reseat them they dont seal very well. The AN type flare is better.
Al
Reply to
Alpinekid
"Alpinekid" wrote in message
a modern car should last for 15 + years, and 150,000 + miles.
Unless you are prepared to spend a HUGE amount of money you will not better this performance...
Now ask yourself this question... If I was offered a 20 year old car, in brand new condition would I want it ? It will have a 3,000 mile service interval, it will have poor power, crude ride, poor petrol consumption, bad road noise......
In twenty years time you will want to junk your everlasting car for something a lot better.
Have you looked at kit cars, mine is all fibre glass, no rust problems.
Jonathan
Davrian 8, BMW M3 Remove AT to reply
Reply to
Jonathan Barnes
An AN type single flare will split the double wall copper brazed steel tube that is used for brake lines
Neither single nor double flare can be trusted if re-assembled absent sealant or a copper gasket.
-Mike-.
Reply to
Mike Halloran
I just said AN type because I read it someplace. I dont really know what it is.
Maybe my problem has been the lack of sealant or copper gasket. I have never seen either used on brakes. What sealant or copper gasket do you use when working on brake line in american cars?
Al
Reply to
Alpinekid
Copper gaskets are often found on banjo bolts, which are seldom used in American cars. They work, once. You are supposed to replace them, or anneal them before reuse.
I, personally, use a vanishingly thin, not quite invisible, film of either Permatex #2 or Loctite Pipe Sealant or RTV. Thin, as in smear a little on your finger, rub the finger and thumb together, then apply your finger to the part, leaving a fingerprint. Smear the fingerprint and assemble the joint. That is of course not an officially recognized procedure anywhere. If it voids your warranty or kills you, remember that I didn't tell you to do it.
-Mike-
Reply to
Mike Halloran
Hmm, RTV in a normal automotive brake system sounds like a literal recipe for disaster. As you tighten the joint a wafer thin film of RTV will be extruded from the joint, into the pipe. I agree, it probably won't break off. I also agree that at least initially there is not enough motion of fluid in the pipes to move it anywhere worse, but what happens the next time you bleed the brakes?
Cheers
Greg Locock
Reply to
Greg Locock
Goobers of RTV that break loose can interfere with an engine's operation by jamming the oil pump relief valve shut. On some random cold start, the pump inflates the filter, the filter gasket blows out, and the engine's lube oil is pumped out on the ground in a few seconds. I recognize the noise it makes, now. And I stopped using RTV in engines for that reason.
A tiny goober of RTV couldn't be a threat to a classical passive brake system, any more than the usual wear and corrosion products found therein. A goober of just the wrong size might be a problem to the complex innards of an antilock brake system. I wonder how they respond to the usual wear and corrosion products?
-Mike-
Reply to
Mike Halloran
I'm not so sure "a real frame" is a feature ensuring or even contributing to longevity. One concern is, even if the frame was painted and finished carefully there will be many pockets to trap dirt and salt. For years it seemed pickup truck frames and suspension were not even painted, relying on a little extra thickness to provide a "corrosion allowance." Our 1980 FORD Fairmont had its barely painted oil pan and rear axle cover rust through. Corrosion protecting a multi-leaf leaf spring is a daunting task.
My vote for a long lasting, repairable and maintainable vehicle is a RWD Volvo, either 240 or 740 series. 740 is much more refined compared to 240. My current ride is a 240 wagon with 230,000 miles. I've had several 240 wagons. In some ways I think they are the perfect vehicle.
On Fri, 24 Oct 2003 19:04:36 GMT, Alpinekid w
Reply to
djtcz

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