As historical naval architecture is of such interest to me, I’m quite drawn to the idea of building a full strucutral model of a ship of the line. The 74-gun third-rate ship was the main type of battle ship of all major navies during the French Revolutionary and Napoleonic Wars, so is an ideal subject. But which to choose? There are a very large number of designs of 74 that were used by the Royal Navy during this period, and they are all fairly similar to one another. You can see the gradual changes in aesthetics over the years, but there were few structural or design innovations until after the wars ended. I’ve chosen to try out some techniques on a hull slice model.
So the choice comes down to a purely subjective evaluation of a ship’s lines. Based on this, I chose the Ganges class design, and specifically HMS Tremendous, launched in 1784 – still the only ship of the Royal Navy to bear the name. In part this is because a very detailed as-built drawing exists, showing the various decorations and figurehead in excellent detail.
I have built a ship of the line before – see HMS Agamemnon – but that was more of a model of a model. The intention here would be to more accurately represent the real ship. Building a full-hull structural model would be a significant undertaking, and I wanted to develop workflows for the various elements of it first, to identify any shortcomings before doing it for real. So a more limited hull slice seemed like an ideal way to test things out. I opted for a slice a little aft of midships, centred around the main mast.
Framing the hull slice
Before starting, I had redrawn the ship’s lines from the original plans as splines in Cinema 4D, and carefully adjusted them to ensure that they were all nice and smooth (fairing). Having selected the area by the mainmast for providing a full body, as well as part of the quarterdeck so that cannons could be included there, I worked out the thickness of the frames at each deck and made both inner and outer surfaces. Once I was happy with those, I started cutting out the numerous frame elements.
Sitting directly on the keel are the floor timbers. Each ‘full’ frame starts as a floor timber for one of the pair, and two first futtocks for the other. The first futtocks stop either side of the keel, and a ‘cross chock’ is fitted over the keel to join them together. On the real ships, the first futtocks were bolted to the floor timber, so these full frames appear like double-thickness frames at this level.
Butting up to the ends of the floor timbers are the second futtocks, with the elements being joined together by filling chocks (you can see these roughly triangular pieces in the end frames of the slice). On the other side of the pair, the third futtocks were fitted to the ends of the first futtocks in the same way. As each element of the frame becomes progressively narrower as you work up to the top, gaps start appearing at this level. In real life, small packing pieces were placed between the two halves of the paired frames where the bolts passed through, but I have left these out here. The gaps allowed for some ventilation and helped reduce rot in the structure.
After the second futtocks come the fourth futtocks, and now their horizontal positioning is important, as the sides of some of these elements define the sides of gunports on the future gundeck. This is why there appears to be a slightly haphazard arrangement to the frames as you progress towards the top. On the other of the pair, the next elements on a third rate are the top timbers. These are scarphed onto the ends of the third futtocks, which means their ends overlap with a diagonal joint. These timbers are again positioned carefully as they define the sides of gunports. And finally, the slightly shorter toptimbers are fitted to the ends of the fourth futtocks. All full frames cover the full height of the hull at that point.
Once the full frames are complete, there are still quite large gaps in the hull. These are filled with the filling frames – ‘half’ or single frames, which are constructed in the same way as described above, just without being fixed to their neighbour. The filling frames are interrupted by the gunports, terminated at, and subsequently resting on the gunport cills. I then placed the keelson over the top of the floor timbers, like an internal keel. This helps secure all the frames in position.
Planking the Hold (Ceiling)
The progression of this build will roughly follow real-world practice, but probably not exactly. The next elements to be added in form the beginning of the planking of the hold, also known as the ceiling (somewhat confusingly). The limber strakes, two of reducing thickness either side of the keelson, create a channel for water to drain into the well, located at the mainmast. Next are the two bands of ‘thick stuff’ on each side, the first being placed over the heads of the floor timbers. This consists of five strakes of thick plank, reducing in thickness with each strake out from the central one. A second band of thick stuff, made from three strakes, is worked over the heads of the first futtocks. These thick bands of planking gave strength to the hull at critical areas. If the ship were beached, she would be focusing most of her weight around these points.
A short distance above the first futtock thick stuff are the two thick strakes that form the orlop deck clamp. The beams for the orlop deck will be placed on top of this band of planking. The gaps between the limber strakes, thick stuff and deck clamps are then filled with thinner planking. It became the practice in later decades to leave some of this filling planking out, to improve ventillation and reduce problems with rot, but during this period the ceiling was essentially fully planked over.
It was at this point that I decided that centring my hull slice around the main mast was not ideal. On the one hand, it will offer more possibilities later for looking at what’s going on inside the ship, but on the other, the planking in this area is very simple. One of the reasons for making this slice is to test out some methods for producing the required elements as accurately as possible. A greater test of this would have been at the bow or stern, where the planking has to contend with the complex curvatures of the hull in those regions. I may need to knock up a more simplistic model later to try things out in those areas.
Internal Riders and Orlop Deck Beams
This ship was launched in 1784. It was not until the second decade of the nineteenth century that ships started to be constructed with diagonal reinforcement. Up until then, all structural stiffening was acheived through the planking, and a series of stout internal frames called riders, that extended up to the underside of the gundeck. Riders were far fewer in number than the actual frames, and in this hull slice, only a single floor rider is present, which crosses over the keelson with an arched hump, leaving a gap beneath for the limber channel.
First futtock riders can be seen starting either side of the limber strakes, and running up to the bottom of the orlop deck beams that have been placed on their deck clamps. The orlop beams are unlike those of any other deck in that they have a rabbet cut along both top edges. The planks of the orlop deck sit down in these grooves, rather than being fixed to the top of the beams like other decks. These planks were fixed together underneath to form sections, that were removable to gain easier access into the hold. The orlop beams also have very little camber. The plans for HMS Tremendous show them without any camber at all, so they have been modelled straight here.
Lodging knees have also been added at the ends of the beams. These horizontal brackets fix the beams in place longitudinally in the hull. They were expensive items, for they had to be made from very specific parts of a tree to ensure the wood grain had the required bend in it, for maximum strength. The gaps shown at this stage will be filled later by the standards, forming a solid mass that braced each beam against it’s neighbour, locking them in place and preventing them disotorting with the movement of the hull in heavy seas. The posts that have appeared in the hold will shortly form the well.
The Well
Centred around the main mast was the well, which will be a prominent feature in this hull slice. This was essentially the lowest part of the ship, once it was afloat, and so all the bilge water tended to drain to this location. The well was a boarded-up structure around this area, inside which was the step for the mainmast, along with the chain pumps, which were used to lift the water out of the well and discharge it over the side of the ship.
In front of and behind the well were extensions to it, with hinged lids, that were used as lockers for storing cannon shot. A standard 74 like Tremendous carried 32-pounder, 18-pounder and 9-pounder cannon, and the majority of the round shot, chain shot, etc for these guns was stored in these compartments. It must have been a very unpleasant job to be sent into them to lift out the heavy iron balls to pass up to waiting hands above!
I have included an access door to the well at the bottom here. This is a feature I have seen on some models, but I am not convinced it is correct. The bottom of the hold would normally have a layer of pig iron and gravel ballast, on top of which the various casks of stores would be bedded. It seems unlikely to me that it would have been possible to use a door in such a location, so this may well disappear in the future.
I have added a very temporary wood texture to some components in an attempt to liven these renders up a little. I don’t like it much so it will be replaced with something better soon. Another reason for doing this hull slice was to develop wood materials that can be applied easily without having to worry about UV unwrapping everything.
Orlop Deck & Start of the Gundeck
Between the orlop deck beams, three ‘tiers’ of lighter timbers were worked, called carlings. These ran longitudinally, and helped to provide some additional support to the deck planking. Shipwrights were not satisfied that this was enough though, and several even lighter timbers called ledges were inserted between the carlings and the lodging knees at the sides of the ship. The orlop deck was a little below the waterline, so of course no guns were carried at this level. The planking was therefore quite thin, but this extra structure was needed because of the way the planking was laid. As only about 1.5 inches at each end of a plank was resting on a beam, there would have been very little support without the carlings and ledges beneath.
The well continued up through the orlop deck, enclosed at this level by a louvred structure. Having subsequently looked at some photos of this structure in HMS Victory, I will need to go back and make some alterations. It also seems more likely that there would have been an access door at this level, with a ladder fixed inside the well. I will make that change at the same time.
You can see that the second futtock riders have also been added in, fixed to the sides of the orlop beams. Planking of the ship’s side at this level consists of a single strake laid over the tops of the orlop beams, to hold them in place. This was followed by a small ventillation gap and then the three strakes of the gundeck beam clamp. These were thick planks that had to support the immense weight carried on the gundeck – twenty-eight 32-pounder cannons, each weighing 56 hundredweight (about 2.85 metric tonnes). Add to that the weight of their carriages, as well as several hundred men.
Finally, I have started work on the massive gundeck beams. These were each made in three peices, with an elaborate tabled scarph joint connecting them all together. In some places, a beam would pass through the location of another feature of the ship, such as the main mast. In these cases, curved ‘beam arms’ were used instead, which were scarphed into the sides of the neighbouring full beam. One complete example of this is visible in this hull slice, along with part of another.
I’ve added a human figure here for scale reference. He’s 5ft 9in tall – on the tall side of average for the time. The orlop deck is quite low – mind your head!
Gundeck structure
Finally for this first part, I have completed the structure of the gundeck. Lodging and hanging knees have been added at the sides of the ship. The orlop deck used a combination of the futtock riders and upwards knees, called standards, to provide rigidity. From the gundeck level upwards, hanging knees were used instead. The type of knee, and direction fitted, was dictated by the need to have an obtuse angle to the knee, as timber of this type was easier to obtain than acute bends. In some locations, one of which is shown against the aft most gundeck beam of the hull slice, it was necessary to angle them to avoid other parts of the structure. In this case, the hanging knee is curved and angled backwards to avoid the orlop standard below.
The network of carlings and ledges is much stouter than on the orlop deck. As mentioned above, this deck carried a very significant amount of weight. As this deck is above the waterline, it also has some camber to drain any water to the sides, where there would have been small drainage outlets called scuppers. The water pumped up out of the well was also discharged at the side of this deck and allowed to make its way out the scuppers.
Looks tremendous, no pun intended. Will this be available as an STL for 3d printing?