Copper plate overlapping (< > 1794) - lower overlaps upper or vice versa?

[Sizzolo]

On many models and YouTube clips I note the builder starts from the sternpost/keel and hence as the plates build up the upper rows overlap those below. However, I note that in the following sources, it appears the rows may have overlapped lower over upper, requiring the plating to start from the waterline:

 

https://www.academia.edu/358814/The_Introduction_and_Use_of_Copper_Sheathing_A_History

"..This system however only applied to British merchant vessels, the Royal Navy used a different method where the horizontal joints faced upwards."

 

Lavery's Book 'Arming and fitting of English Ships of War'

"On the first ships to be coppered, one sheet seems to have been placed directly above the corresponding one on the strake below; by 1779 this had been changed, and the strakes were staggered, as in brickwork"

 

So, before I start placing thousands of plates on HMS Diana, is the general view that, it is accurate for a 1774 ship to be coppered, starting from the waterline, rather than the keel?

 

I note on a few YouTube clips of the USS constitution (same year, different continent but likely similar/same tech) that this does indeed appear to be the case (lower over upper) but it's not easy to tell.

 

[druxey]

On British Naval ships, plating began at the keel upward and from aft forward. Upper and aft edges of the plates gave the overlap. 

[Bob Cleek]

13 hours ago, druxey said:

On British Naval ships, plating began at the keel upward and from aft forward. Upper and aft edges of the plates gave the overlap. 

The engineering thinking being that the "from aft forward" "forward plate's aft vertical edge overlapping the adjacent after plate's forward vertical edge" reduces drag and reduces the chances of plates being torn off if abraded by anything (e.g., flotsam) that might be struck. Similarly, the "bottom to top" "lower plate's upper horizontal edge overlapping the adjacent upper plate's lower edge" reduces the chances of plates being torn off if abraded by anything if the ship takes the bottom at low tide. (Of course, if the ship takes the bottom for any other reason, the copper sheathing will probably be the least of her problems!  )

Edited February 2 by Bob Cleek

[Sizzolo]

7 hours ago, druxey said:

On British Naval ships, plating began at the keel upward and from aft forward

Can you supply your sources for this assessment?

[Sizzolo]

4 hours ago, Bob Cleek said:

"bottom to top" reduces the chances of plates being torn off if abraded by anything if the ship takes the bottom at low tide

I’d suggest the opposite may be true. If exposed, the lower edge could be lifted upon contact. If the seam is on the upper edge it can’t be lifted through contact from below. Therefore, one should start from the top row and plate from top-down. 

I spotted a nice period painting that showed a ship being coppered and clearly shows the shipyard started from the waterline - I’ll have to dig it out. Also, I might need to make another visit to the UK national archives to get to the truth of the matter. Hopefully though someone will post a definitive reference that clarifies things for RN frigates of the period.

 

Unfortunately Boudroit’s French ‘74 books don’t cover copper plating at all (not that I’ve found - pls correct if there is mention) which is a great shame. I’ve a feeling ‘authentic and accurate coppering’ for the scale model maker may be a relatively recent development in our art. 

Edited February 1 by Sizzolo
Added comment about Boudroit’s 4 books.

[Wacom]

Nepean Longridge mentions plating from the waterline down in “the anatomy of Nelsons ships”

[JerryTodd]

More often than not, water moves past a hull from bow to stern, so that sheets forward should overlap the ones aft.  The same basic principle as the shingles on the roof of your house.

In the vertical is another matter, as ship's roll, there really isn't a general flow of water.  It could be argued that pitching causes higher water pressure moving up the hull, and why you might want to copper top-down.   An argument for bottom-up coppering is the sheets closest to the waterline are the most likely to be damaged; over-zealous cleaning, rubbing against the dock, ice, etc.  While either format can be repaired, the bottom-up would be a little easier to repair.

Bottom-up coppering also covers the points and narrow ends of cut sheets better than the other way, which leaves them exposed and prone to catch stuff, like seaweed, and get pulled loose.
Every photo of a coppered ship, out of the water, that I've seen, the copper was applied bottom-up.  Before photography is anyone's guess, since every source I've seen contradicts every other source I've seen, like Lavery and Longridge.

On that note; copper was nailed with flat headed nails, counter sunk in pre-punched holes, so the nail heads were flush with the sheet's surface.  If your coppering looks like they used the Titannic's rivets, it doesn't matter how they overlap.

Edited February 3 by JerryTodd

[allanyed]

11 hours ago, Sizzolo said:

I note on a few YouTube clips of the USS constitution (same year, different continent but likely similar/same tech) that this does indeed appear to be the case (lower over upper) but it's not easy to tell.

It is indeed difficult to tell in the video, but the photo below of the Constitution bottom SEEMS to be shingled with upper over lower.

Allan

[allanyed]

Did a little more digging and found the following in contracts for the Echo (1782) , Aurora (1776), and Astrea (1808) which I thought was very interesting.   I do not recall ever seeing this on a model where the coppering is done on the keel before the false keel is secured to the bottom of the keel.  It makes total sense as the false keel is sacrificial so why protect it as well as prevent it from doing its job. 

 Allan

 

As the Ship is to be partly coppered before the False Keel is put under, Care must be taken that there is Copper, as shall be directed, put all Fore and Aft between the Main and False Keels, properly turned up and fastened.

Edited February 2 by allanyed

[Bob Cleek]

4 hours ago, Sizzolo said:

I’d suggest the opposite may be true. If exposed, the lower edge could be lifted upon contact. If the seam is on the upper edge it can’t be lifted through contact from below. Therefore, one should start from the top row and plate from top-down. 

You're absolutely correct! I wasn't very clear, was I? It's all Druxey's fault. His post got me all flabunged..    

 

I edited my post to stater it more clearly. The easiest way to remember it is "like the scales on a fish."

 

In fact, Druxey and I were "talking about apples and oranges." The "apples being the order of applying the plates and the "oranges" being the manner of overlapping the plates. The historical research indicates that the process of applying the copper plates was, as Druxey stated more eloquently than I did: "On British Naval ships, plating began at the keel upward and from aft forward. Upper and aft edges of the plates gave the overlap."  That said, it turns out there were a variety of sheathing pattern methods that evolved over time for reasons of economy and ease of application. The "keel upward, aft forward" process was apparently the earlier. Later plate application patterns were all over the map. Some did apply plates ub belts from the waterline down. Others applied them in belts from both the waterline and the keel simultaneously.  Some applied the plates in bands. Other patterns applied the plates diagonally. 

 

So... the "rivet counters" have not only the plate overlaps to obsess over but also the various plating patterns used at various times on particular ships!

 

This article on the most recent re-coppering of USS Constitution discusses the various copper sheathing patterns used on that ship over the years in a fair amount of detail: New Copper Sheathing - USS Constitution Museum (Partial excerpt follows: US Navy publication.)

 

When coppered in the summer of 1797, Constitution‘s lower hull required “12,000 feet of sheet copper” and thousands of copper nails. There is no 18th century plan of the layout of the copper sheathing, but it is probable that the workers at Edmund Hartt’s shipyard began at Constitution‘s stern, down at the keel, and worked their way both forward and upward with row upon row of copper. Each sheet would have overlapped one inch on all sides, with the vertical joints between the sheets facing aft. This created a smooth “fish scale” affect to the hull, thereby preventing the sheets from being lifted by the action of the water. It is understood that the Royal Navy laid its warship copper with the horizontal joints facing upwards and it is possible that Constitution‘s copper was so installed, as depicted in the illustration below.

 

 

Illustration by Stephen Biesty showing a shipyard worker installing USS Constitution‘s first copper sheathing in the summer of 1797.  [USS Constitution Museum Collection. © Stephen Biesty, 2015.]

 

Two mid-to-late 19th century photographs of Constitution, hauled out of the water, offer the rare opportunity to observe, at close hand, the layout of her copper sheathing. Both the 1858 Portsmouth Navy Yard and the 1875 Philadelphia Navy Yard photos clearly show the “no belt” pattern to Constitution‘s copper.

 

 

Salt paper photographic print of Constitution at the Portsmouth Naval Shipyard in 1858. Note the jagged edge of the unfinished copper sheathing. [USS Constitution Museum Collection]

 

 

USS Constitution in a sectional dock at the Philadelphia Navy Yard, ca. 1875. This photo shows the angle of the ship’s copper and a portion of the hull planking. [Courtesy Naval History & Heritage Command Detachment Boston]

 

As described by Mark Staniforth in his article “The Introduction and Use of Copper Sheathing – A History,” the “‘no belt’ copper pattern resulted from the greater distance from the keel to the waterline amidships than at either bow or stern. This resulted in a ‘bowed’ pattern where there were more rows of copper sheathing amidships and the rows curved sharply upwards at the bow and stern.” [From The Bulletin of the Australian Institute for Maritime Archaeology, Vol. 9, No. 1 of 2, 1985, 30]

 

For the 1927 restoration, a plan was drawn of the proposed layout for the new copper sheathing. Lieutenant John A. Lord’s “U.S. Frigate Constitution Copper Plan,” #25002, dated December 12, 1929, shows an outboard profile of the ship with perfectly straight lines superimposed on the lower hull, representing the lines of copper sheathing. Given the extreme curves to Constitution‘s lower hull, it is nearly impossible to lay the sheathing in perfectly parallel rows.

 

 

“U.S. Frigate Constitution Copper Plan”, #25002, December 12, 1929. [Courtesy Naval History & Heritage Command Detachment Boston]

 

USS Constitution was re-coppered in the 1973-1974 dry docking and again in the 1992 restoration. Each time, the pattern of laying the sheathing on the ship’s lower hull has essentially followed the “goring belt” method established in the 1927 restoration. And, at least since the 1973-1974 re-coppering, the uppermost two rows or so of copper have been covered with red anti-fouling paint, to prevent any marine growth right at the ship’s waterline.

Edited February 2 by Bob Cleek

[Mark P]

I have a strong feeling that the plating is applied from the waterline downwards; I will look into this later, when I have time, and post what I can find.

 

all the best,

 

Mark P

[DaveBaxt]

All this talk of where the overlap is top or bottom, fore or aft . However I was under the impression that the thickness of copper plates which are supplied in most kits or even copper foil are too big for a lot of the scales used ie 1:64,1:72 any scales lower than 1:64 then perhaps then perhaps we might get away with these copper plates supplied in kits. I recently applied the amati copper plates on my model at a scale of 1:64 and did not have any overlap. Not sure if this is correct but at the time I thought so. Correct me if you do not agree.

[Morgan]

2 hours ago, Mark P said:

I have a strong feeling that the plating is applied from the waterline downwards; I will look into this later, when I have time, and post what I can find.

 

all the best,

 

Mark P

This is certainly what Bugler says of Victory:

 

”The sheets were worked with laps, clinker fashion down, and butts, clinker fashion, aft.  The strakes were run as far as practicable parallel to the waterline.  At the fore end they were laid roughly parallel to the fore foot.”

 

My reading is ‘Top Down’ and ‘Stern to Bow’ as the lay direction.

 

Gary

[allanyed]

FWIW, below is the overlap as drawn by Peter Goodwin in The Construction and Fitting of English Man of War, pp 225-26.  He does show the plating overlap the strake above.

Allan

 

[Sizzolo]

All extremely helpful references - thank you so much. I'd hate to be half way through and find a very convincing reference which contradicts how I started!

 

For DaveBaxt - I'm not sure if its a relatively recent development but a different approach is using copper 'plumbers tape' which is the method I'm following for this one. I've recreated the rivet pattern using my home made tool, and cutting the strip into pieces before applying. James H provided an absolutely stunning demonstration of this technique in his build of Chris Watton's HMS Indefatigable which you can see on page 12 of the build log:

You'll also see the little tool I made to recreate the rivet pattern on page 13.

 

[Sizzolo]

 

The following appears to be recent new plates attached to Ol'Ironsides and it looks like they applied the plates from bottom to top, then applied the rows of nails along lower edge. It looks like they place a few rows, then the next row (bottom) would be slid under the one above before nailing.

Looking at other videos of USS Constitution it may be the case the layers switch as some close ups hint lower over upper instead of upper over lower. The references above do seem quite firm though so, I'll do my usual and try to find the original admiralty order or shipyard doc in the references in the books mentioned. There's likely something somewhere!

Edited February 2 by Sizzolo

[DaveBaxt]

19 minutes ago, Sizzolo said:

All extremely helpful references - thank you so much. I'd hate to be half way through and find a very convincing reference which contradicts how I started!

 

For DaveBaxt - I'm not sure if its a relatively recent development but a different approach is using copper 'plumbers tape' which is the method I'm following for this one. I've recreated the rivet pattern using my home made tool, and cutting the strip into pieces before applying. James H provided an absolutely stunning demonstration of this technique in his build of Chris Watton's HMS Indefatigable which you can see on page 12 of the build log:

You'll also see the little tool I made to recreate the rivet pattern on page 13.

 

Thank you sizzolo for the link. Which is a very fine build with some excellent workmanship. I am no expert but as I understand it, the rivet pattern you mentioned is in fact nails and again they are too small to see at 1:64 and above, at least at a normal viewing distance. However again I do believe everyone should do what they are happy with as it is their model. I suppose it all depend upon what you are trying to achieve.

Edited February 2 by DaveBaxt

[Sizzolo]

13 hours ago, nzreg said:

Nepean Longridge mentions plating from the waterline down in “the anatomy of Nelsons ships”

found the quote:

"...in laying the strakes the work must run from the keel upwards and from the stern forwards. I am told, however, on very good authority, that while this general principle held good for merchant ships, it did not apply in the Navy. On naval ships the upper edge of a lower strake overlapped the lower edge of the strake above it"

... but Longridge doesn't say who the good authority was unfortunately...

[Morgan]

The reasoning for ‘Top down’ and ‘Stern to Bow’ is to negate the effect of friction on the plating.

 

Consider the impact of friction as the ship moves through the water, this was enough to wear down the copper plating over time. The same forces will act on the seams of the copper plates.

 

Forward facing seams would be more prone to opening up as friction has each individual seam to act upon. A rear facing seam allows the water to slip over the seam with a much reduced impact.

 

The same applies with the horizontal seams, the effect of water on the ships hull is to constantly push it upwards, hence the seams were also upwards facing to mitigate this frictional force that would otherwise work its way much easier into those seams.

 

Gary

[wefalck]

This is how the restorers of HMS GANNET (1878) in Chatham thought it should be done:

Their Portuguese colleagues restoring DON FERNANDO II E GLORIA (1843) in Lisbon seem to agree on top-down, but the course along the waterline seems to have been put on last:

I don't have shots that show the keel, but there is the possibility, that the plates around the keel were put on before the plating from above arrived.

On the other hand, putting on the plating around the keel last also makes sense, because these may be damaged when a ship touches ground and are theneasier to replace. Dito. for the course along the water-line that may be easily damaged by boats coming alongside.

 

Edited February 2 by wefalck

[druxey]

When I wrote earlier 'from the keel up' I did not mean that the keel itself was covered first; just the hull planking. Those plates were put on next to last, with a small flange over the keel/garboard to overlap the first row of hull plating. The very last was under the keel itself, with another overlap to the side keel plates.

[Sizzolo]

17 hours ago, Bob Cleek said:

"like the scales on a fish."

Absolutely fantastic - thank you Bob for the comprehensive study and the link. It really appears over the decades after the introduction of plates, the methods and patterns are quite variable. What you posted also helps me understand the YouTube clips which appear to suggest in places the USS constitution has both upper row over lower and vice versa.

 

The other examples support the evolution of the methods over the years with those great pictures from wefalck.

 

Putting all this together and the period of my build (1794) I think I'll go with the 'starting from the waterline' method, especially as Morgan's quote from Bugler's Victory book (that I can't afford) really supports this.

 

Thanks everyone!

[Sizzolo]

21 hours ago, allanyed said:

It makes total sense as the false keel is sacrificial so why protect it as well as prevent it from doing its job. 

Hi Allan - that reminded me of something I read earlier so I looked up the quote:

Lavery's 'arming and fitting of English ships of war 1600-1815' p64

"The false keel.. was vulnerable to damage in any grounding...After 1780 it was to be filled with small nails, both copper and iron.. The main hull was protected between by copper between the main keel and the false keel, so that in a sense the latter could be sacrificed"

[allanyed]

Sizzolo

Thanks for the source.  Now, I wonder if any modelers coppering the bottom will be reading this string of posts and show the false keel outside the sheathing on the keel itself.  I read the paragraph just now and I do wonder what he means that the false keel was filled with small nails.  Is it heavily nailed like hob nailed boot soles or something else?  For our purposes these would not be seen anyway, but I am curious.   

Allan

[Blue Ensign]

Back in 2017

I used an ebony strip to represent the 'False' keel applied over the coppering.

 

B.E.

[Sizzolo]

I just tried a scale reproduction using a needle. Looks a bit like woodworm though. I like the ebony example. 

 

[Thukydides]

6 hours ago, allanyed said:

Sizzolo

Thanks for the source.  Now, I wonder if any modelers coppering the bottom will be reading this string of posts and show the false keel outside the sheathing on the keel itself.  I read the paragraph just now and I do wonder what he means that the false keel was filled with small nails.  Is it heavily nailed like hob nailed boot soles or something else?  For our purposes these would not be seen anyway, but I am curious.   

Allan

Perhaps it meant that small nails (as opposed to large ones) were used to make it not hold on to the keel as well as of the nails had been driven deep into the keel.

 

Alternatively is it possible the false keel was still coppered? Just separately than the rest and the small nails redera to nails that held this copper to the false keel but didn't go through to the keel itself?

[JerryTodd]

I never rely on restorations and recreations as a source for a model, unless the model is of the ship as it exists.  Constellation is no longer coppered, they can't afford it, or much else, and the people in charge are not historians.  The current spar deck arrangement was based on 1:96 scale plans from A.J.Fisher drawn based on the ship as she appeared in 1941, which is not how it was during the American Civil War, as the restoration folks claim to be working toward.

When I coppered my model of Constellation, which was launched in 1855, I looked at photos of ships, mostly 1860's to the 1890's.  There are no other real sources than this.  As stated, restorations are typically no more knowledgeable, and when consulted, usually refer you to their sources (which is how I found out about the AJFisher plans), which in most cases are the books we already consult; Lavery, Lees, etc.  There is no "Arming and Fitting of American Ships of War" and the closest thing to it, "The History of the American Sailing Navy" isn't the same sort of book, it's more of a narrative history with a few details rather than a technical guide.

At any rate; trying to figure out how Constellation was coppered by looking at photos of her and her contemporaries that showed it; I settled on the "no belt" pattern mentioned a few posts earlier.
I painted the hull copper, just-in-case, as this is a working model.  I used peel-and-stick copper tape sold by an electrical supplier online.  The tape is real copper, uncoated, and meant for indoor/outdoor use.  At 1:36 scale I needed tape at least 1/2 inch wide which model suppliers that have it, charge a great deal for, the electrical supplier cost less than half what model suppliers wanted.

(click the pics to see the larger versions)

 

I made dimples in a piece of sheet aluminum with a blunted nail, and pressed that onto the front of the copper piece on a "mars" eraser to imply the nail pattern.  This also made peeling the paper backing off much easier.

Starting at the ship's heel (the lowest point aft end of the keel), I began applying the copper sheets, wrapping them around the back edge of the stern post.  The sheets overlap about 1/16 of an inch.  Each piece was pressed by hand and gently rubbed with the mars eraser to press it to the hull.  This pushed the embossed dimples back out, making a countersunk, flat-head-nail look I was happy with.

 

This went on for a few thousand pieces of tape.  On occasion, a piece would have to be cut because it's end was too close to the end of the piece below it.  I cut pieces so the end would be 1/4" or more from each other when they would have been closer than that otherwise.  When one side was coppered, I worked on something else to let my fingers heal, the coppered the other side.  Finally I laid what I called the "dragon scales" on the stem and bottom of the keel.  The copper was trimmed to stop at the waterline, and a single row of sheets runs around the hull, covering all the points created by this trim.  The copper is therefore 7/16" above the LWL.

To the best I could determine, this was how Constellation and her contemporaries were coppered from the 1850 into the 1900's.  This may not apply to ships of other nationalities, or built in private yards.  Other than the belted, or non-belt patterns, I was mainly concerned with it's appearance fitting the 1:36 scale of my model, which I think it does.
This is how the copper looks 9 years later, after several sailings in the brackish waters of the Chesapeake Bay's tributaries.

Edited February 3 by JerryTodd

[Sizzolo]

1 hour ago, JerryTodd said:

Constellation

Great example of well-researched information supporting the logic behind the design of the resultant beautiful model. 

[allanyed]

12 hours ago, Blue Ensign said:

I used an ebony strip to represent the 'False' keel applied over the coppering.

Very nice!!!   You are a big step ahead of most, if not all kit designers and modelers.  

 

 

Allan,