As I understand it, the galvanising of steel is the addition of a protective zinc coating. The most common form of which is hot-dip galvanising, which involves the dipping of the steel component into a vat of molten zinc.
For individual car-body panels, I would imagine that this would have limited success, because once they are welded together, the welded joint will be a weak spot - rust protection-wise.
The most logical way to protect a car body would be to build it, and then dip the entire structure into the molten zinc vat - not sure if many manufacturers do this though, or would even consider doing it for mass-production of cars.
Plating any part of a car body is not conducive to planned production - it’s a time and money factor. It also detracts from new car sales, not to the benefit of any industry. Treating a whole ‘built’ car is impractical and in my book impossible, - go figure. Sorry.
Re Galvanising…
Yes, Chris, you’re pretty much correct, and if you try to weld a galvanised steel panel , it really doesn’t like it…!
Moreover, it introduces a metallurgical notch, which will either crack or rust more rapidly than the surrounding metal.
The only way is to dip (preferably hot) the complete welded structure, ensuring that all surface (inside and out) are coated, while permitting the very noxious plating salts to run out of any box sections.
That’s a tall order…and usually involves serious manipulation within the plating/galvo bath.
Not really economically feasible… Same thing goes for E-coating.
Now if you made the structure from aluminium, it might be a different story, but even then salt will kill it evetually unless it’s thoroughly passivated/plated. The recent Jaguar aluminium chassis/bodies have their share of corrosion issues, I’m told…
But, on the whole I do agree that Mazda are guilty of ‘spoiling the ship for a ha’porth of (underseal) tar’!
In posting no.19 Gerry brings up a valid point about the rusting of cars being a natural built-in obsolescence. This does actually help keep the wheels of the motor-manufacturing industry turning (sorry for the pun !), by creating a constantly-revolving market for new cars as the old ones decay.
Another good point he makes (and sorry if this is going off-piste Andrew), is that manufacturers also have another weapon in their armoury to make sure we keep buying their new cars, and that is the supplying of spare parts for old models.
I have always been under the impression, from my life as a motor mechanic in the 70s and 80s, that car manufacturers were legally bound to continue supplying spares for a minimum of ten years after the cessation of production of any particular model. However, I noticed on the MX-5 Parts web site a few weeks ago, that they stated that chrome fuel-filler caps for NCs were no longer available as a genuine part from Mazda, so it seems that this law does not necessarily cover every kind of spare part, as this is only two years after production of the cars finished - perhaps ‘bling’ is excluded from this statute.
We in this country, are perhaps fortunate that we have a healthy classic car culture, and many businesses have been built up over the years manufacturing and supplying spares and accessories for vehicles long since out of production - I for one hope this situation continues.
Hmm, not all manufacturers used to apply the ten year rule as an absolute cut off.
When my nineteen year old Mk1 Cavalier needed another brake equaliser valve (because a welch-plug in it was rusting with a tiny weep of fluid and I was reluctant to merely bodge repair a safety critical part in a car driven by SWMBO), it was fifteen years after the last one Mk1 had been made. To my surprise Vauxhall were quite happy to put an order on the factory to have one made for me, apparently most of the older parts were not held in stock merely made to order - JIT system. To my much greater surprise the cost of the part would be significantly more than the market value of the car. By then I had already decided life is too short to mess about in scrapyards again so it was scrapped, and part of my endowment policy payout bought a new Vectra. The Vectra lasted without any problems until a small spring broke in the cambelt tensioner.
In both cases the cars were free of rust and everything worked reliably for two decades, until the crunch time when the failure of something small and costing only pennies tipped them into the bin, coincidentally when I had an unusual surplus of cash.
In a similar situation, When I still had my last job, I took over my wife’s Fiat for a couple of years, and the head went. Alloy head - no spares available. I was told there were five of us all looking for the same item, and we were each asked to contribute £200 towards a new mould, so Fiat could produce one for each of us. = £1,000. We had to wait a couple of months for it, and the local garage that fitted mine didn’t call me back for a recheck after (which they were supposed to do) so I had a head leak with steam everywhere. I gave them some stick, and they re torqued the head bolts, which they forgot to do. Expensive for each of us, but cheaper than a new car, S/H or not.
900 CC engine, but went like a bat out of hell, I loved it. Cornered well too, but was hopeless on motorways!
Strictly a town car, but served me well.
My last customer made a fortune out of making spares - 3 times the price of same item on a built printing machine. Such is life.
Well, I’ve now had an answer to my enquiry as above from Fiat Customer Services. They tell me that the bonnet and the boot lid are aluminium, and that the other body panels are made from galvanised steel. So, surprise,surprise!
Not so much surprise, modern Fiats are quite good for rust resistance. The panels will most likely be stamped from pre-galvanised sheet before assembly, but the welds and cut edges can still rust if not properly sealed.
However, there is galvanised, and there is galvanised. Thirty years ago I put up a new fence and strung some galvanised wire along it to support the roses etc; it still has no rust. But the same gauge of galvanised wire I bought recently for Espalier training my new apple trees is already rusting in many places after only one winter.
A prime example I’ve quoted before - My late Uncle worked at Aritoc’s for many years, eventually became head electrician. During the war Aristoc switched to making parachutes, out of Nylon. - Silk was hard to get, and expensive. (So the old term “Hit the silk” became obsolete)
When the war ended, Aristoc switched back to making stockings - from the original Nylon mix,. First production was given to directors wives, who were over the moon. After a year of wear and constant washing they were still good as new. Aristoc changed the nylon grade, obviously concerned that they had to keep stocking life to a lower figure if they wanted to continue in business.
Same principal continued throughout industry, which is why post war cars became rust buckets after a year or so, while pre-war cars continued for several years after. My first lawn mower had a cast aluminium base, eventually replaced by a steel one. The ally base was still good - the engine wasn’t, so a friend took the base and fitted his old engine as his metal based one was shot. It goes ever onward.
Ford in America made six V8 saloons out of stainless steel in the thirties, as an experiment. Five were still on the road in the late 50’s, two having had engine replacements, but bodies are probably still good today. Ford never tried that again! IIRC the sixth was waiting for various parts, but the body was still perfect.
Cookers used to be made partly with cast metal parts - now they consist of thin sheet steel, much to the concern of my wife, who screams every time the metal expands with a loud BANG! (I smile!) - She’s high strung. The list is endless. Paint - lasts for a couple of years, whereas lead based paint lasted seemingly forever in my younger days. The only industry - if you can call it that, which seems dedicated to extending life is health, and that’s done with medicine. As my GP said a few years ago, when I asked if he could change the type of Atorvastin that I’m on, was “You can stop taking the lot if you wish - but you’ll die!”
That stopped any argument.
^^^ I’m with you on the cooker quality these days. Last year had a kitchen makeover so new cooker time. In short there was nothing out there that my wife fancied so we went with a replacement from the same manufacturers of the out going one, fancier knobs, sleeker looking hob rings etc but basically it was the same cooker, even the same model name. The weight difference was most noticeable, the new one much lighter, verging on the flimsy side. Anyways immediately we picked upon two faults with it and so disappointed with the quality we returned it for a refund, never even had it fitted. We are still using the same (old) one after having it checked over and reinstalled.
Same with our central heating boiler, had to be replaced because the igniter unit was dead and parts no longer available otherwise??? Built by a company called Wilson in Liverpool (Now defunct?) with some 45+ years of use. Took 5 of us to lift it out and put in in the truck, the installer’s apprentice brought in the replacement in on his own! Estimated working life? 5-8 years according to the fitter!
Rusted cars are the luck of the draw from day one really. If you’v ever been to a new car storage area and seen cars stood up to their sills in water you’ll know what i mean. I have seen cars in this state often and it’s not unusual at all. You could see within a hundred yards that some of these cars were almost under water but cars just that short distance away were high and dry. Now a vehicle that’s been stood in a muddy field or a sunken paved area will not have started life as well as the cars next door that were high and dry. The thing is,you will never know for sure how your car was stored until of course the rot sets in,then you might have a clue,
Apart from the very unfortunate NB front chassis rails issue, most of the rust on our MX5’s is in none structural areas so although can look very ugly is not a serious issue. The surface rust on heavy gauge steel sections such as wishbones and sub frames,generally,isjust that,surface rust. Perfectly treatable.
The heated rear window in my NC stopped working. Got my local MX5 specialist to take a look and after much searching concluded it was a break in the wiring harness. To relate the harness that runs from the rear window to the passenger footwell was going to cost £250 but they’ve not be available from Mazda for ages and there is a big backlog of orders to the factory in Japan. You would think these would still be readily available. The local garage did a their own fix which cost me £50 and everyone works fine now.
The subject of spare parts for out-of-production cars cropped up the other week.
Having been in the motor trade back in the 70s and 80s, I was always under the impression that motor manufacturers were legally bound to continue producing spare parts for cars for at least ten years after the cessation of production. I’m sure though, that there are plenty of underhand ways open to manufacturers, to reduce the burden of producing parts for older cars which they don’t really want to do - creating a backlog is probably one of them.
You were probably fortunate that it was an easily-traceable fault, and that your local garage could fix it.