As I was busy with Jean Bart, Dunkirk and ships, I wondered when the transition from wood to steel occured.

In the time living near the Leie in the Fifties
https://en.wikipedia.org/wiki/Lys_(river)
I was watching the "binnenlanders" (barges?, inland vessels?) in wood but with a small propeller at the end before and in the rudder...



What a difference with nowedays steel vessels



But back to the vessels of the high seas...

At the Belgian coast I have seen in the Fifties the Belgian fishing fleet turn from wood to steel. And I am nearly sure that the "ijslanders" (fishing around Iceland, Scotland, Denmark) were already in steel from before WWII.
The "icelanders" one big family, when an English ship came in trouble everyone assisted and vice versa...

But I disgress again...
As I see it a big step was made during the American War of Seccession with the Ironclad ships
https://www.britannica.com/video/195087/advances-technology-armament-propulsion-conduct-outcome-American

And about that transition a history from the Greenwich museum:
https://www.rmg.co.uk/stories/topics/shipbuilding-1800-present

As said in the above link: Isembard Kingdom Brunel seems to be key figure in the transition among others  with his Great Eastern
http://www.ikbrunel.org.uk/ss-great-eastern



And if one wants a complete survey in American:

The greater strength of wrought-iron or steel certainly gives several advantages over wood for ship construction - and accordingly it is tempting to see the transition simply as an almost inevitable technological progress - however I think that the shift to iron/steel was to a large degree driven by shortages of timber. Towards the end of the 19th century the use of iron and steel for ship-building was widespread in the UK and the rest of western Europe and yet in North America, despite the USA's strong industrial base, especially in iron and steel manufacture and with a proven capability for building advanced iron/steel warships, a great many ships were still being built almost entirely of wood - probably for the simple reason that good timber remained readily and cheaply available.

Water-powered blast furnaces came into widespread use in western Europe during the 16th century and for the first time there was the means of producing, in a continuous process, many tonnes rather than just a few kilos of iron (as cast pig iron) although this metal still usually required additional processing to be made into a more usable form (wrought-iron). However, with the exception of minor fittings such as nails, bolts, straps and brackets, the first serious indications of iron being used as a substitute for timber components in ships are from around the latter half of the 17th century (at least in England and France). In 1670 when the shipwright Sir Anthony Deane built the 1st rate 'Royal James' at Portsmouth, Samuel Pepys, then Clerk of the Acts for the Navy Board, rebuked Deane for not using authorized materials. After visiting the dockyard he wrote to Deane saying, "... that you have of your own head, without precedent, as well as without the advice, or so much as the privity, of this Board or the Commissioner upon the place, presumed to lay aside the old secure practice of fastening your beams in your new ships with standards and knees, and in the room thereof taken upon you to do it iron". Deane, defending the case that his 'iron dogs' were a stronger method of securing beams, replied, "... between you and myself, the King must build no more ships, if nothing can be invented but knees..., we having not one knee in the yard". The King, later seeing Deane's letter, supported his actions. In all probability the immediate shortage of suitable timber was because of resources being directed towards rebuilding London after the Great Fire of 1666. Nevertheless the need to find suitable timber for warship construction was a long-running problem that had been worrying successive governments since the time of the Spanish Armada, and was still a continual concern over a century later during the Napoleonic wars. What Deane's "iron dogs" actually were is uncertain but the fact that it is a non-standard term suggests that it was not simply a case of substituting, like-for-like, parts in wood with those from iron, but rather it required some design modifications. However that is all speculation as the 'Royal James' was burnt and sunk at the Battle of Solebay in 1672 and Deane's innovation never seems to have become standard.

But while a shortage of timber was clearly an incentive to replace wood with iron, it was charcoal production for iron smelting that was itself largely responsible for depleting the forests. The demand for chacoal to produce iron would only be alleviated in the early 18th century, principally by Abraham Darby's development of the coal/coke blast furnace. However even then, while this made cast-iron cheaper, this material is not in itself suitable to withstand the stresses and strains of a ship at sea. Techniques to convert brittle cast-iron to tougher bar-iron were developed from the mid-18th century (especially the puddling process invented around 1800) but large quantities of tough wrought-iron only really became available in the first half of the 19th century with the development of better forging methods and innnovations such as the steam hammer and large steamengine-powered rolling mills capable of shaping wrought-iron into the long bars and large sheets required for ship construction.

Large scale steel production only started with Henry Bessemer's invention of the forced-air converter process in 1855. Prior to this steel-making methods had only been able to produce kilos rather than tonnes at a time, and so steel had been an expensive commodity used for a limited number of purposes where a particularly hard, strong or stiff metal was essential, as in the cutting edges of tools and weapons, wear-resistant bearings in clocks and scientific instruments, and for springs, or the strings of musical instruments. With the Bessemer Converter the widespread availability of inexpensive steel rapidly led to wrought-iron being replaced by low carbon steel for almost all purposes, including in ship-building, and wrought iron is no longer commercially produced.

Nevertheless, although the strength of wrought-iron and especially steel make them eminently suitable for ship construction, where timber was readily available, such as in North America, even large ships were still being largely if not entirely built from wood well into the 20th century.

Edit - I have changed my original wording a bit, especially (I hope) to clarify the distinctions between iron generally, pig-iron, cast-iron, wrought-iron and steel - but without getting to wordy. In particular be aware that while wrought-iron is chemically nearly 100% pure iron (as is low-carbon steel), pig-iron and cast-iron are considerably less pure (typically containing around 2% of carbon and other stuff, sometimes more). I have also deliberately hyphenated 'cast-iron' (ie, the specific product from a blast furnace), to distinguish it from iron, or an iron-based alloy, that has been 'cast' (ie, melted and then poured into a mould). I've similarly hyphenated 'wrought-iron' (again as a specific product), to distinguish it from any iron alloy, including steel, that has been 'wrought', ie hot-forged by hammering, rolling, pressing etc. Apologies for being such a metallurgical pedant but I've found these terms often cause confusion, such as the frequently asked question: but why does cast-iron contain less iron that carbon-steel?

MM thank you very much for this review from which I learned a lot that was new to me. 
As the shortage of wood that led at the end to more steel ships, as new procedures came in use.

I had to look to the difference between cast iron and wrought iron. My field of knowledge is more the protection of steel by paint...and of course in the salted water of the sea that steel has above the paint to be protected by sacrificial anodes
https://www.marineinsight.com/tech/understanding-sacrificial-anodes-on-ships/

And yes the change with the Bessemer procédé...and here in Belgium it was Cockerill...first working with William I of the "Netherlands" and then after the independence in 1831 of Belgium working with the Belgian government (he wanted only to produce and gain money, whoever was the "boss" in the country) and made Belgium to one of the most industrial powers in the world only second to the UK. 
https://en.wikipedia.org/wiki/John_Cockerill_(company,_1825%E2%80%931955)
MM, as an aside, you, who that well knows the Belgian situation via your familiy-in-law, here nearly the history of that process via the story of Cockerill...
https://www.brusselstimes.com/news/magazine-all-news/46484/how-200-years-of-industry-shaped-belgium-s-identity-2/

But back to the resistance to build steel ships instead of wooden, due for I guess whatever reason...
https://www.penobscotmarinemuseum.org/pbho-1/ships-shipbuilding/steam-steel-ships-and-end-wooden-shipbuilding
As the time of the "clipper", even those with a steel hull still the rest in wood...
And before the Suez channel they were still in competition against the steam engined ships in steel...
https://en.wikipedia.org/wiki/Iron-hulled_sailing_ship
https://www.marineinsight.com/types-of-ships/5-biggest-and-magnificent-sailing-ships-of-all-time/



Kind regards, Paul.

PaulRyckier wrote:

MM thank you very much for this review from which I learned a lot that was new to me.

Oh Paul, my particular viewpoint should never, ever, be seen as the definitive truth and indeed my thoughts, as expressed here, are often exaggerated or even deliberately presented in provacative terms, just to prompt some sort of response.

More specifically however, and despite being a Belgophile, I have to point out that Cockerill was just another businessman who personally never invented anything new: indeed his entire financial success seems to have been built on borrowing/stealing the ideas of others. Yes, he was a very successful industrialist, but when compared to someone like Bessemer, his enduring legacy is negligible to say the very least. Henry Bessemer, whether for good or ill in the long term, certainly transformed the world. Cockerill did nothing comparable, nor especially noteworthy or even memorable - hence, probably, his very brief and rather perfunctory entry on the wiki link that you, yourself, posted..

Meles : Please, for your own safety, do not visit Dudley nor more especially Gornal of you intend to refer to Darby as the inventor of coal/coke produced iron. The adherents of the "Dud" Dudley school will, in relays, read the "Metallum Martis" until you recant that heresy.

Well quite, although to be fair Dudley's expertise might well have been deliberately handed on to Darby for him to make a financial success of it (they were related: Darby was a great-grandchild of Dudley's sister) however, although he managed to get backing to try out his ideas, I'm not entirely sure Dudley ever reliably achieved what he so grandly claimed and he certainly never seems to have made much money from it. Similarly in France one should never mention James Nasmyth and steam hammers without also mentioning François Bourdon - both men acrimoniously claimed the other had stolen their design. But that was sort of my whole point about questioning the simple, linear, historical narrative: it is rarely simple.

Meles meles wrote:

Large scale steel production only started with Henry Bessemer's invention of the forced-air converter process in 1855. Prior to this steel-making methods had only been able to produce kilos rather than tonnes at a time, and so steel had been an expensive commodity used for a limited number of purposes where a particularly hard, strong or stiff metal was essential, as in the cutting edges of tools and weapons, wear-resistant bearings in clocks and scientific instruments, and for springs, or the strings of musical instruments. With the Bessemer Converter the widespread availability of inexpensive steel rapidly led to wrought-iron being replaced by low carbon steel for almost all purposes, including in ship-building, and wrought iron is no longer commercially produced.

Nevertheless, although the strength of wrought-iron and especially steel make them eminently suitable for ship construction, where timber was readily available, such as in North America, even large ships were still being largely if not entirely built from wood well into the 20th century.

As evidenced, for instance, by the American and Japanese navies using wooden flight decks on their aircraft carriers until late on into the Second World War (1943 in the case of Japan and 1945 in the case of America). This contrasted with the European navies of Britain, France and Germany who all had carriers with armoured flight decks in service before 1939. The Italian aircraft carrier RN Aquila (converted in 1942) had a partially armoured flight deck with armoured protection above the fuel and munition stores.

While Bessemer’s converter ushered in a revolution in steel production and ship building from the 1850s onwards, another inventor working in the 1850s, Joseph Swan, was developing carbonised paper for use as filament in light bulbs. The 2 innovations may seem unlinked at first, yet Swan’s invention was a slow-burn in comparison to Bessemer’s. The ongoing development of carbon fibres since then, however, has meant that we are today probably witnessing a further revolution in ship building with some of the world’s navies beginning to eschew steel in favour of carbon fibre. The jury is still out on this though. Needless to say, also, that the world’s smugglers have for decades sought to revert to wood rather than steel in an effort to avoid detection by radar.

Meles meles wrote:

More specifically however, and despite being a Belgophile, I have to point out that Cockerill was just another businessman who personally never invented anything new: indeed his entire financial success seems to have been built on borrowing/stealing the ideas of others. Yes, he was a very successful industrialist, but when compared to someone like Bessemer, his enduring legacy is negligible to say the very least. Henry Bessemer, whether for good or ill in the long term, certainly transformed the world. Cockerill did nothing comparable, nor especially noteworthy or even memorable - hence, probably, his very brief and rather perfunctory entry on the wiki link that you, yourself, posted..

 
MM, of course you are right and although I prefer our Baron Empain above Cockerill, because of his colourful life and his daring projects as the Paris Métro and his city near Cairo: Héliopolis it were again the engineers and inventors, who made it possible...
And after all in Paris they had alreday the example of London...
https://focusonbelgium.be/en/Do%20you%20know%20these%20Belgians/Edouard-Empain
And of course we had in the Seventies the kidnapping of the third Baron Empain who lost part of a finger in the episode...
https://www.bbc.com/news/world-europe-44583096
Kind regards, Paul.

Vizzer wrote:

While Bessemer’s converter ushered in a revolution in steel production and ship building from the 1850s onwards, another inventor working in the 1850s, Joseph Swan, was developing carbonised paper for use as filament in light bulbs. The 2 innovations may seem unlinked at first, yet Swan’s invention was a slow-burn in comparison to Bessemer’s. The ongoing development of carbon fibres since then, however, has meant that we are today probably witnessing a further revolution in ship building with some of the world’s navies beginning to eschew steel in favour of carbon fibre. 

 
Vizzer, what one learns here each day on this board as about the carbon fibres 
and yes I checked it about your:
"Needless to say, also, that the world’s smugglers have for decades sought to revert to wood rather than steel in an effort to avoid detection by radar."

And what about a fibreglass polyester hull?
https://www.afloat.com.au/2020/07/17/fibreglass-boat-rotten-transom/
And I have already some experience with it, as I made in the time an inside "hull" of some 10 cm high and on the flat "load platform?" of three fish transporting vans with a flat water resistant "multiplex?" wooden layer and then on it the hull with glassfiber wooven mats and polyester and accelerator...

Kind regards, Paul.

Vizzer wrote:

... As evidenced, for instance, by the American and Japanese navies using wooden flight decks on their aircraft carriers until late on into the Second World War (1943 in the case of Japan and 1945 in the case of America).

I'm not sure that's entirely true in the case of 1940s Japan. Japan was a small, intensively-industrialised and densely-populated island, but with very limited timber or other significant natural resources and so its industry was reliant on overseas trade, and then, with international trade embargoes, pre-war Japan simply had to work with whatever she could get. So, in the 1930s and during the opening years of the war, the decks and flight decks of most Japanese warships, whether armoured on not, were usually covered in linoleum (or the Japanese equivalent). Lino is typically made from linseed (flax) oil, or indeed any similar plant or mineral based oils, blended and cooked with pine-tree resins, plus fillers such like sawdust and powdered chalk. It is an artificial product which can be made relatively cheaply without any expensive refined petroleum product.

(That's probably why lino was also promoted in post-war, cash-strapped, 1950s Britain: Burntisland in Fife, located adjacent to a fairly rough oil-shale deposit and with ready access to the woollen dregs left over from the local carpet-manufacturing industry became, at least briefly, Britain's lino manufacturing centre).

With a pre-war US oil embargo in place on Japan, it was not until early 1942 when Japan seized the oilfields in the Dutch East Indies, that crude-oil based products became more readily available to Japanese industry. The situation further changed when Japan gained control of South-East Asia and so got access to the huge timber resources of Burma and Malaya. Accordingly it may well be that it is these developments as the war progressed, that prompted the return to traditional hard-wood planked decks for Japnaese warships.

=WWII RN ships used a brown linoleum-like deck covering known as corticene to improve grip.

Meles meles wrote:

(That's probably why lino was also promoted in post-war, cash-strapped, 1950s Britain: Burntisland in Fife, located adjacent to a fairly rough oil-shale deposit and with ready access to the woollen dregs left over from the local carpet-manufacturing industry became, at least briefly, Britain's lino manufacturing centre)

Not particularly relevant to the discussion about shipbuilding, but just to clarify and correct what I'd written from faulty memory:

Linoleum was an invention of Frederick Walton which he successfully patented after establishing an experimental factory in west London in 1863. Walton's patent expired in 1877 and production then became more widespread in Britain and abroad, spreading to Scotland and in particular to the town of Kirkcaldy in West Fife. Kirkcaldy was already a major centre for the manufacture of waxed canvas floor-cloth and so within a few decades over a dozen linoleum manufacturing companies had been set up there. The largest of the Kirkcaldy linoleum producers and eventually the the biggest manufacturer of lino in the world was the company of Michael Nairn. Linoleum production remained the principal industry in the town until well into the 1950s when there was still a huge market for lino, both domestically and globally (probably boosted, albeit only temporarily, by post-war reconstruction) but thereafter the development of alternative floor coverings (such as PVC) meant a sharp contraction in demand and by 1986 Nairn's linoleum factory in Kirkcaldy was one of only three surviving factories in the world still producing genuine linoleum. Soon after the company ceased lino production and was then wound up.

Essentially the making of linoleum is a culinary process involving the thorough mixing of ingredients, then rolling and baking/oxidising the product into tough sheets. The raw materials are:
1. Softwoods: from which the wood flour and rosin are derived.
2. Flax: from which production of the basic ingredient, linseed oil, is obtained.
3. Cork Oak: used to produce ground and finely graded powdered cork for the surface texture.
4. Chalk: in powdered form to act as an inert inorganic filler.
5. Jute: which provides the hessian or canvas back for the linoleum sheets.

The heaviest gauge of linoleum used to be known popularly as 'battleship linoleum' as it was originally manufactured to meet the specifications of the U.S. Navy for a covering on enclosed warship decks, although it was also much in demand for use in high-traffic situations such as factories, offices and public buildings. Most U.S. Navy warships removed their linoleum deck coverings following the attack on Pearl Harbor as they were considered too flammable, although linoleum continued to be used in U.S. Navy submarines and, as GG has said above, on Royal Navy warships where a similar product 'Corticine' was used. Japanese battleships and carriers generally had wooden decks (pre-war built vessels used teak but ships built later into the war had decks of Japanese hinoki cypress because of shortages), while cruisers and destroyers generally used a red-brown linoleum, except where the decks were left as painted steel. However this standard practice probably varied as the war progressed and problems with obtaining the 'correct' material were increasingly encountered.

Five miles south-west of Kirkcaldy is the town of Burntisland, which was a site for the mining and processing of oil shale, with the Burntisland Oil Works being established in 1878. At its peak around the beginning of the 20th century, the average daily output of shale from the mine was 500 tons, which yielded 15,000 gallons (57,000 litres) of crude oil. The crude oil was refined on site and the main products were burning and lubricating oils, paraffin candles, paraffin wax, and sulphate of ammonia for fertiliser. I don't think any was used in the nearby manufacture of linoleum. Also, while the Kirkcaldy/Burtisland area - being a long-established centre for the manufacture of floor coverings - certainly had several carpet-making factories, I can't find anything to suggest that wool was ever used in the manufacture of linoleum: jute or hemp always seem to have been the thread used for the backing canvas cloth.

Another important historical development in iron/steel shipbuilding was the move from riveting to welding.

A rivet consists of a smooth cylindrical shaft with a head on one end. On installation, the rivet is placed in a pre-punched or pre- drilled hole through the steel plates, and the cylindrical tail end of the rivet is then 'upset' (ie deformed) by hammering to form another 'head', resulting in a fastening that is roughly a dumb-bell shape. The rivets used in shipbuilding were themselves made of wrought iron or steel and were installed and hammered while red hot so that the metal was soft and could be shaped quickly but also so that, as the metal contracted on cooling, it pulled the metal plates tightly together. Riveting required three men*; the first, operating the portable furnace, tossed the red hot rivet to the second, who caught it in a mitten or bucket, then inserted the rivet in the hole and supported the head end, while the third worker hammered the tail to form the second head. It was a very skilled job and with the red hot metal rivets being tossed around injuries were common, as was deafness due to the incessant hammering. *And though I said 'men', during WW1 and WW2 the riveters in both US and British shipyards were often women.


Women rivet heaters, with their tongs and catching buckets, Puget Sound Navy Yard, May 1919.

In 1939/41 my dad, while awaiting call-up, was on a government training scheme based at Swan Hunter's shipyard on the Tyne: he once commented that the sound of thousands of riveters all working at the same time was deafening when you were close and sounding rather like constant machine-gun fire when you were a bit distant. A ship required a great many rivets: the Titanic contained about three million rivets, in total weighing about 1,200 tons, and at the time of her construction the Harland and Wolff shipyard employed over 30,000 people, a great many of them riveters.


A riveting squad at work at John Brown's shipyard, Glasgow in 1949. There's no sound (perhaps because the original sound was drowned out by the infernal racket of the riveting) and you'll need to click "watch on youtube" for it to play. Note the two men, one on each side of the plate/support being riveted together; the one on the tail side of the rivet is using a pneumatic rivet gun (like a jackhammer) but in earlier times it would have been done with a simple heavy, hammer. Note also that despite the red hot rivets being thrown around, there's not much 'elf an' safety in evidence nor much protective clothing, other than a leather apron, an asbestos mitten and an old cloth cap.  

By contrast to riveting, welding fuses two pieces together by using an external high heat source to locally melt the metal, often with some additional filler metal added to the molten material to produce a slightly raised seam. Hammer/forge welding is an ancient technique but shipbuilding requires a more portable method. Electric arc welding and oxy-acetylene gas welding techniques were developed towards the end of the nineteenth century and the first trials of welding for ship construction were made during WW1. Welding started to be used in shipbuilding during the 1930s but only really became widespread during WW2, principally in the US with the construction of Liberty ships and tankers; in Britain many ships were still being built of riveted construction well into the 1950s.

The introduction of welding into shipbuilding permitted faster and cheaper ship construction as larger pieces of metal could be joined together to make the ship’s hull than was possible with riveting, and the process required a smaller and generally less-skilled workforce. Welded joints were more water tight than riveted ones and the resulting vessel was lighter and, having a smooth hull, could move through water with less friction and thus use less fuel than a riveted ship.


Women workers using electric arc welding in a US shipyard during WW2. Note the finished long, smooth, welded seam, visible, horizontally at waist height, during the first ten seconds. Note also how generally quiet it is when compared to riveting.

But there were problems. During the war there were several losses of new welded ships which seemed to have been caused through catastrophic failure of the hull. These had all occurred out at sea and so it was difficult to acertain the exact cause but the general view was that these losses were due to faulty welding (especially when later investigations did uncover faulty working practices at some yards). Then in January 1943 the SS Schenectady, a 'National Defense Tanker', having successfully completed her sea trials was moored at a fitting dock in calm weather, when, without warning and with a noise audible for at least a mile, the hull cracked almost in half, just aft of the superstructure. The cracks reached down the port and starboard sides almost to the keel, which itself fractured, jack-knifing upward out of the water as the bow and stern sagged to the bottom of the river. Only the bottom plates of the ship held. Although there had already been ten similar failures (and there would be several more) this was the most prominent as it occurred in full view of the city of Portland and was widely reported in the newspapers even under wartime conditions.


The Schenectady in January 1943. Amazingly, given her broken state, she was fully repaired and successfully re-entered service just 3 months later in April 1943. After the war the US government sold her but she continued with Italian owners as a regular oil tanker, until finally scrapped in 1962.

The cause of the fracture was not fully understood at the time. The official Coast Guard report again gave the cause of failure as faulty welding, while the Board of Investigation considered factors as diverse as "locked-in" stresses, sharp changes in climate, or systemic design flaws. However later research (after the war) indicated that the failure method was due to the grade of steel, which could become highly brittle in cold weather. It is now known that low carbon steel exhibits a temperature-sensitive ductiile-brittle transition in failure mode, such that while the metal will usually deform and fail in a ductile manner, at lower temperatures it will fracture and fail in a brittle manner. Unfortunately for the type of steel then almost universally used in ship construction, this transition temperature is within a few degrees of 0°C, ie temperatures typically encountered in northern seas during winter.


At temperatures above the transition temperature failure occurs in a slow ductile manner which absorbs energy, but at temperatures below it, the failure is by brittle fracture, which occurs rapidly and requires considerably less energy. This abrupt transition is a particular function of iron and steel (a consequence of its body-centred cubic crystal structure). Alloys based on copper (brass and bronze), aluminium (duralumin etc), lead (and lead-based solders), tin (and pewter), magnesium (ultra light-weight 'alloy' frying-pans etc), and titanium-based alloys (such as in the critical parts of aircraft, and in the hulls of 'stealth' submarines) ... all these do not usually show this type of abrupt ductile/brittle behaviour. But then very few of these materials are as strong and tough (nor as cheap) as steel to start with.

The metal used in riveted ships was similarly prone to brittle fracture, however a riveted construction meant the failure was limited in extent: a few individual plates might well crack across but the overall structure was not compromised and the individual failures could be patched and repaired. It was only in very severe impacts that riveted ships would catastrophically fail: Titanic ultimately sank because most of the rivets along her side all snapped and the hull plates cracked, in a brittle manner, due to the sudden impact and the cold: the metal did not flex, bend, crumple nor tear to absorb the blow of the iceberg. But a crack in a weld seam, once initiated, may well run the entire length of the join as the weld is effectively a long, one-piece casting, and so can result in the vessel completely breaking apart, as occurred with the Schenectady.

Now that this is understood, the steel used for ships is specifically modified (principally by the addition of a small amount of manganese and nickel) so that the ductile-brittle transition temperature is well below 0°C, ie the failure mode should always be ductile and so the metal will gradually deform absorbing energy, rather than suddenly snap. Nearly all ships are now constructed by welding rather than riveting, and in a collision a modern cruise liner should crumple and bend rather than crack and snap like the Titanic. Rivets are now rarely used in shipbuilding, however, in a rather more sophisticated form they are still extensively used in aircraft construction.

MM, it is not fully from wood to steel in ships, but about your transition from riveting to welding. It seems to be also been a long winding operation.
And I was nearly sure that people of Ostend from the "Wagon-Lits" incorporated in a shipbuilding "Beliard" had spoken to me of "riveting" of locomotives even till WWII and perhaps longer. It don't exist anymore but they have renovated the "Orient Express" overthere. And many times, as it was in the Fifties open for normal passengers I could as a student use the Wagon-Lits train Zagreb-Ostend from Ghent to Ostend.

And see: "riveting" on a locomotive...



And as I was working together with the steel lab in our metal constructing factory, I am always interested in your "welding" stories as about the SS Schenectady...I had already heard about "brittleness" but not in that context. What one learns here each day on the board.

PS: And I read this evening in a discussion between train drivers about riveting, welding and bolts, one who defended the bolts as you can exactly! measure that with a (torsion meter?)...

Kind regards, Paul.

Metal bolts, nuts and screws are fine - but, you have to be able to manufacture them in large quantites if you intend to build a ship or locomotive.

The first metal screws for fastening metal pieces together appear in the 16th century in clock and armor manufacture but although mechanical screw-cutting lathes had been constructed at about this time, most of these early threaded fastenings were still custom-made by hand and they would continue to be for the next two centuries. Industrial, mechanically-manufactured, mass-produced v-thread screws and bolts only started to become available around the beginning of the 19th century once modern powered screw-cutting lathes were developed (principally through the work of Henry Maudslay). However even then there was little standardization except within individual companies, and so repairs could often only be done by the original manufactures as the bolts made by one company would not fit the nuts of another. The first national standard screw thread was devised and specified by Joseph Whitworth in 1841 and was largely prompted by the surge in the use of metal in the manufacture of steam engines, warships and railway locomotives. Whitworth's standard, BSW (British Standard Whitworth), was in general use at least in the UK and throughout the Empire, until gradually replaced by modern ISO metric threads. In a similar way the sizes of bolt heads and spanners all needed to be standardised too.

None of these are trivial issues and until modern international ISO standards were ubiquitous there were frequent problems. For just one example; in 1919 Morris Motors in England, which used BSW threads, took over the French Hotchkiss engine works which had moved to Coventry during the First World War. The Hotchkiss machine tools were of metric thread but metric spanners were not readily available in Britain at the time, so fasteners were made with metric thread but Whitworth heads. Until 1955 British Morris and MG engines were nearly all built using metric threads but with bolt heads and nuts dimensioned for Whitworth spanners and sockets. Accordingly when you took your Morris Minor, Riley or Wolsey to a garage, it was as well to ensure they had all sizes and standards of taps, dies, bolts and spanners.

All this just further illustrates how the shift from wood to iron in shipbuilding required a whole set of associated technical innovations. A large wooden ship, such as HMS Victory, was built with tools that were little more sophisticated that those found in the tool bag of a carpenter one might employ to hang a garden gate: adze, axe, woodsaw, woodplane, spokeshave, hole-boring auger, chisels, hammer and nails. An iron or steel ship however requires powerful equipment to cut the metal to length, bend to shape, and punch or drill precisely-sized holes in exact locations, plus accurately machined nuts and bolts (and the correct sized spanners and wrenches) in addition to having portable furnaces to heat rivets or the equipment to weld parts in situ.

The following is a rather lyrical, even whimsical, short public information film from the 1940s (there is no exact date but it looks to have been made during the war as soft, 'feel-good', propaganda for home consumption), but it does nevertheless show some of the unique complexities of constructing a ship in metal rather than wood. (Note the temporary bolts to hold the hull plates in place while they are rivetted, note also the noise of the riveting).



In that film, along with the press-tool operators, rolling-mill operators, foundrymen, crane-drivers, riveters, welders and apprentice boys, I was pleased to see mention of the painters. My grand-dad had his own painting and decorating business in Newcastle upon Tyne, but during WW1 he worked as a painter in Palmers' shipyard at Hebburn (South Tyneside) as he was too old for conscription into the forces. At Palmers, amongst other ships he painted the battleship HMS Resolution, and while working there he was also bombed by a Zeppelin. Always a bit of a cynic he once commented (to my dad, he died years before I was born) that the most important thing was to get the officers' quarters done well: the rest of the ship didn't matter so much, but if there was just so much as a single paint run where the officers would see it, then the Admiralty inspector would order the paint job to be completely re-done.

MM, thank you for another great reply. Great at least for me, as I during several episodes in my life came in contact with what you mentioned.

To start with about the srew making with lathes. Yes, to have screw bolts you needed lathes and standardization. In the garage technic evening school we had all kind of screws "English" Whitworth and "metric". And later I had a set of taps to make inner screwthread and a set of rings for outer thread. Of course two sets of each, one in "English" thread and one in "Metric".

And yes, that "standardization"...For our branch of paint on steel, we worked mostly with ASTM and if it was an exception it was mentioned. As for instance AFNOR or DIN...at the end of my time it became as you said easier with the ISO (International Standards Organization).

I enjoyed your 15 minutes film of the shipyard. My father was befriended with the night watchman of a shipyard in Ostend. So I was many evenings with that man, before his nightshift on the yard. The year that I was there the yard was building a fisher trawler. I have seen with him the evolution in the building. And in thise days (the Fifties) it was all welded (no rivets anymore I guess) or it had to be in the inner cabine light metal panels with rivets



But during that year I have never seen the completed ship...

And thank for the story about your grand-dad and marine painting. I was lucky that I was not in the marine painting. In WWI it was still rather a mystery how the protection of the paint worked in that salt environment and I suppose they had to have it done essentially from "loodmenie" (they translate: orange lead?) as adhesion layer and I guess filmthinkness was also important. If I have time I will do some research, but only for my own knowledge as ex-paint specialist)
And yes we did painted panels weathering  tests together with the Marine in Zeebruges. And they said that the elevated saltcontent in the air could be measured up to 20 km inland...

Kind regards, Paul.

The use of Iron in the construction of ships at the beginning of the 19th century has already been mentioned. A wrought iron frame skeleton with a wooden skin was common practice by the 1840s when the first all iron ships began to appear.
However, an iron hull comes with problems of its' own, namely that an iron hull is just as vulnerable to marine organisms as a wooden hull, especially in the tropics. A wooden hull can be protected against this by the use of copper sheathing, but this is not possible with an iron hull as the two metals react with each other and produce galvanic corrosion.
Ships which were intended to spend long sea voyages, merchant ships such as tea clippers and warships such as cruisers continued to be built with a composite hull (iron frame, wooden planking, copper sheathing) well into the 1860s.
Iron hulled ships began receiving protection with the invention of copper sulphide anti-fouling paint which started development in the 1850s

Clipper ship Cutty Sark, cutaway showing iron framing. Long range warships, eg CSS Alabama were also composite ships.



Galvanic corrosion is not confined to the 19th century. USS Independence in 2010 (wiki):

In 2010, the Navy asked for an additional $5.3 million to correct problems found in the sea trials. Galvanic corrosion caused by an aluminium hull acts as an anode in contact with the stainless steel propulsion system with sea water acting as an electrolyte, and electrical currents not fully isolated, caused "aggressive corrosion."

You can see an early example of iron in shipbuilding here - partly used to supplement the availability of the "grown knees" indispensible in building large wooden ships. Iron reinforcement from the 2nd decade of C19th saw ships more than double in size - from c. 2000 tons of HMS Victory to c. 6000 tons of HmS Duke of Wellington.

https://www.youtube.com/watch?v=R-y_oE4WKeg

Another use of Iron in ships was for water tanks.

I cannot find a great deal about this subject, except that iron water tanks began appearing, in Royal Navy ships anyway, towards the end of the Napoleonic Wars. A couple of references is about all there is;


"Some obscurity seems also to surround the manufacture of Dickinson’s iron tanks, the patent for which was acquired by Maudslay at some time between February, 1811, and April, 1815. The manufacture was greatly expedited, and the quality of the product improved, by the use of punching and shearing machines devised for the purpose, apparently about 1820, and described in general terms by Henry Maudslay, the grandson, in 1858, when it was also stated that “these machines had been extensively employed by the Governments of England, France and Russia.”


"The sailing Royal Navy needed wooden casks for fresh water, alcohol and food. Consumption peaked in 1805: Deptford Yard issued 72,253 tight casks and 72,073 dry casks, and the annual average at Portsmouth was 10,000 and at Plymouth 21,700. From the 1780s cask staves were principally English beech, from 1800, oak from Quebec, but the cost and scarcity of new staves in wartime led the Victualing Board to trial wrought-iron water tanks for ships’ ground tiers, in the Royal Oak, from 1809–12. In 1812 Dickinson and Maudsley were contracted to supply 1,000 two-tun tanks, which were delivered in 1813, and then to supply 1,000 more at 160 per month to Deptford. However, casks were used for food throughout the nineteenth century."

I'm into history, literature, politics, current affairs that kind of thing, but science is beyond me. So don't laugh when I say that I've no idea how ships float! How come a brick sinks, but a ship millions of times heavier floats! Is it magic?

Four minutes will explain it;

Oh ... I rather preferred the explanation that it's simply due to magic and because a ship weighs the same as a duck, or something like that:

I feel a bit thick now considering it was worked out over 2000 years ago.

The necessity of armouring ships came about with the invention of the Paixhans shell gun, which could fire an explosive shell, extremely destructive to a wooden hull ship. Paixhans had developed his gun in the 1820s, but it was the 1840s before they began appearing in warships (Admirals of the time were very conservative in their outlook)

The shells which produced those very extensive ravages upon the Pacificator hulk in the experiments made at Brest, in 1821 and 1824, upon the evidences of which the French naval shell system was founded, were loaded shells, having fuzes attached, which, ignited by the explosion of the discharge in the gun, continued to burn for a time somewhat greater than that of the estimated flight, and then exploded; thus producing the maximum effect which any shell is capable of producing on a ship.
— A treatise on naval gunnery by Sir Howard Douglas



In November 1853, a Russian squadron armed with the new shell guns wiped out an Ottoman squadron at Sinope in the Black Sea. This one sided victory caused other naval powers to look at ways of countering these new weapons

Sinope 1853, 



France used armoured rafts during the Crimean War to attack Russian shore fortifications at Kinburn on the Dnieper River in October 1855.

French armoured battery of the Crimean War. These had to be towed to the theatre of operations by paddle steamers:


The next step. Fitting armoured protection to a self powered ship, capable of operating on the high seas, in this case the frigate Gloire. Designed by Henri Dupuy de Lome, Gloire was a steam & sail powered frigate but with 12cm thick iron plates bolted onto a 43cm wooden hull. Experiments showed that this was capable of withstanding the most powerful guns of the time. The appearance of the Gloire in August 1860 began a whole new era of warship design.

Model of Gloire 

I feel a bit more thick than MarkUK since I have never even given a thought to the subject! Somehow Polynesian explorers made their way from Taiwan to the Pacific to set up their communities on islands there before making their way to NZ/Aotearoa and becoming what we now call Maori. And they did this using just long canoes. Even just coming here in their waka took more than a month. From the TEARA site: The first settlers arrived in Aotearoa (New Zealand) in large waka from Polynesia. The journey lasted up to a month, and the waka were big enough to carry many people and enough food. These ancient craft were probably double-hulled – rather like two canoes side by side. Māori tribes trace their ancestors from these important waka.
They must have made deliberate trips with women, since they settled here.

I find that notion very puzzling. Why sail out into the open ocean with your family in the hope of finding land one day in the future? I'm sure someone must have gone ahead first, perhaps got swept off in a storm, found land and made it back with the news. 
If I lived back then and someone said "let's load up a boat with a month's worth of food and water and see what we can find........and, oh yes, bring the kids" I'll have not so politely declined.

"The Black Snakes of the Channel"


The British response to the Gloire were the two the Warrior Class armoured frigate, Warrior herself and Black Prince laid down in May and October 1859 respectively.

Unlike the French ships, the Warriors were built with iron hulls, with their vitals protected by an armoured box of 4.5 inch thick wrought iron over 18 inch thick teak backing. To ensure buoyancy, the ends of the ship were unarmoured. The potential battle damage to these areas was mitigated by the inclusion of 92 water tight compartments. 

The ships weighed in at more than 9,000 tons, required a crew of 707 and cost £377K each. Their Penn Horizontal Single Expansion Engines could drive them at a maximum speed of 14 knots, fast enough to catch and destroy any other ship then in service.

HMS Warrior, now a museum ship at Portsmouth;

Triceratops wrote:

A wooden hull can be protected against this by the use of copper sheathing, but this is not possible with an iron hull as the two metals react with each other and produce galvanic corrosion. Ships which were intended to spend long sea voyages, merchant ships such as tea clippers and warships such as cruisers continued to be built with a composite hull (iron frame, wooden planking, copper sheathing) well into the 1860s.

Clipper ship Cutty Sark, cutaway showing iron framing. ...

Your illustration (above) of Cutty Sark does seem to depict copper sheathing on the hull, however she was actually sheathed in Muntz Metal.  

Muntz metal (also known as yellow metal) is a brass alloy composed of approximately 60% copper, 40% zinc and a trace of iron. It is named after George Fredrick Muntz, who had a brass manufacturing business in Birmingham, and who commercialised the new alloy following his patent of 1832. As a hull sheathing material Muntz metal has several advantages over pure copper. It is considerably stronger and physically more durable than soft ductile copper, while during manufacture when rolled red hot it is sufficiently ductile than it can still be made into very thin sheets. Its greater strength also means it is suitable for making into the bolts to attach the sheathing plates onto the wooden hull, thereby avoiding having to use either iron bolts (liable to galvanic corrosion) or copper bolts (liable to break or  bend). Moreover as Muntz metal has 40% of the copper metal replaced by cheaper zinc (cheaper because of early 19th century advances in extracting zinc form its ores) the total cost of sheathing a ship was greatly reduced, to about two-thirds of the price when using copper. Most importantly the alloy maintained the same anti-fouling abilities of pure copper sheet since in seawater copper still gradually leached out from the alloy, poisoning any organisms that attempted to attach onto a hull sheathed in the metal. Starting in 1837 with fifty ships sheathed with Muntz metal, the numbers effectively doubled every year or so until by 1846 (when Muntz’s patent expired and other manufacturer's started producing it) whereupon Muntz metal became the material of choice for nearly all new-built and renovated ships. Muntz made a fortune, especially when the metal also proved eminently suitable for many other ship fittings and even for ships' propellers.


The hull of Cutty Sark (built 1869) clad in yellow Muntz metal rather than reddish copper.

Actually, Munz metal isn't that good. It de-zncs, leaving a "sponge" of copper. Modern "Naval brass" replaces c. 1% of the zinc with tin, which makes it much more corrosion resistant. Really high-priority components (cleats, rowlocks etc) are frequently made of bronze - the durability makes the cost acceptable.