woodrat
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I felt the need for some colour so I have painted the Angry Duck. I hope its not too cartoon like. The knobs along the neck and head are seen on several pottery images and may represent att achment points for feather or hair crest. The second crutch for the mast and yard is installed. Next is the installation of "hogging truss" Cheerio Dick
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There is ample evidence from art of the Old Kingdom of Egypt onwards for hogging trusses. Hogging is the tendency for a boat, when on the crest of a wave with its stern and stem unsupported, to bend in its mid-section. This risks the boat breaking up. In order to prevent this the egyptians looped heavy rope around the stern of the boat, ran the rope over crutches along the centreline of the boat and looped around the stem of the boat. The rope was tensioned with a Spanish windlass. This relieved much stress from the joints of the boat and made it more seaworthy. As the mycenaean war galley would also have a tendency to hog, it is reasonable to suppose that some form of hogging truss would have been employed on these seagoing vessels. As no art or shipwrecks from the Bronze Age have survived which show a hogging truss, it is a matter of speculation as to how this would have been done. So, let’s try. In the trieres (trireme) of the Mediterranean of several hundred years later there are references to what were called the hupozomata (hupozoma singular). This term means an undergirding and was meant to longitudinally strengthen the trireme to do much the same job as a hogging truss. There has been much argument in the learned literature as to whether the strengthening rope passed under the keel, around the outside of the hull or along the centreline of hull. Without belabouring you with the arguments, the first option is not likely as the rope would prevent launching. The present consensus is that hupozomata (and in a trireme there were likely several of these) passed along the centre line of the hull under the main beams and was connected with a bridle of plaited rope (koruphaia) passing around the stern of the vessel. The other end of the hupozoma was attached at the stem somehow or encircled it. Also there was a mechanism (tonoi or entonoi) which allowed tensioning of the hupozomata. We don’t know what this mechanism was but Plato mentions a “spindle” of some kind. As rope changes its length depending on whether it is wet dry, such a mechanism would have to permit adjustment while the vessel is at sea. To demonstrate how important the hupozomata were, the greeks only applied them to those triremes which were in active service and removed them from inactive triremes. In other words, the triremes were not allowed to go to sea without them installed and tensioned. To return to our war galley, clearly a much shorter vessel than a trireme, structural integrity was just as important in the Bronze Age but they may used simpler methods. So, I postulate a mechanism intermediate between the simple hogging truss of the egyptians and the complicated hupozomata (for, after all, they were just another way to do a hogging truss) of the age of the trireme. And I have a cunning plan which cannot fail Dick
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Ian, in answer to your question on my mycenaean blog, there is definitely good evidence from the archaeology of mast steps. The following drawing is of the Chretienne A wreck from Madrague de Giens (150 - 100 bce) which shows the mast step on a large block on the keelson . There is an aft facing curved surface and an inclined plane which suggests that the mast is removable Also see Casson "Ships and Seamanship etc" page 208. The slots besdide the mast step may be for a tabernacle. Also see this article on mast step coins: The International Journal of Nautical Archaeology (2007) 36 .2: 317–324 doi: 10.1111/j.1095-9270.2006.00132.x MAST-STEP COINS AMONG THE ROMANS D. N. CARLSON Mast-Step Coins among the Romans Deborah N. Carlson Nautical Archaeology Program, Department of Anthropology, Texas A&M University, College Station, Texas 77843–4352, USA The evidence for mast crutches is more iconographic as Louie da Fly has previously shown. I know of no crutches found in ancient wrecks. Hope this helps a bit Dick
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The accommodation for the steersman at the stern is installed. At the forward end, a partial platform behind the stempost allows the head warrior to brutalise the natives but allows him to duck behind a pavise should the natives get too uppity. Note the bird shaped figurehead roughed out. This has been seen on several pottery depictions of these vessels. Dick
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Much to my surprise I seem to have built a forecastle! Once the upper bank of rowers was inserted, the central walkway (or galumphing platfrorm for warriors) was planked. The lines of pilons lining the walkway will be used for the housing of shields. In the after part of the walkway a large compainioway is seen which will give access to the underdeck and to the stern. I need to give some consideration to where water would be stored. Weapons and food could be stored under the central walkway/deck. Would water be carried in amphorae or skins?? As these vessels were not ocean crossing, large amounts of water and food would not have been carried. They would travel along the coast from beach to beach and live off the sea and land, presumably extorting provisions from locals as they went. When not in use it is likely that the mast and yard were lowered onto the crutch and derigged. The mast and yard would have been lashed along the central walkway until next needed.. Next job is the ox-hide weather-and arrow-shield for the upper bank of rowers Cheers Dick
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Woodrats are slow to anger. Here are the effects on the hull shape by varying the l/b/ratio. This may help you decide. L/B = 2.1 L/b =2.5 l/b = 3 Cheers Dick
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If you like but this would give a length of keel /breadth of midship frame of about three. You decide. Dick
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I dont know what total l/b means! Please use length of keel/breadth of midship frame. It is explicitly documented that fifteenth century carracks or cocha were around 2.5. This I would regard as a logical starting point. Dick
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I would suggest only using length of keel/breadth of midship frame and forget I ever mentioned length between perpendiculars. I still suggest 2.5 as a starting point. If you are planning POB at large scale, you are going to need at least a jigsaw or a fretsaw and elbow grease and I would suggest good quality plywood. Dont rush in. I spent years collecting and making tools before I cut the first wood for my first scratch build the USF Essex. Use the collective hive mind of the MSW tribe to its full extent. Dick
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are you talking of length of keel or length between perpendiculars? It makes a difference. Let us assume it is length of keel. For venetian galleon 16th century Pre Theodoro gives keel length to breadth ratio as about 2.6:1. This would be higher if you use length between perpendiculars. For an english galleon of 16th century length to breadth about 3:1. BUt thise is not likely for a 15th century nao. I imagine spanish would be similar to venetian in most regards. As far as 15th century practice, have a guess but I would say 3:1 is a tad high and would tend to go for the ratio of 2.5:1 (I base this on the figures given for venetian naves in F C Lanes Venetian Shipbuilders of the Renaissance. There were no set rules and shibbuilders varied. Dick
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Thanks, Mark. Here are the missing pics. The mast is seen lying on its crutch. The upper bank of rowing benches is now added Cheers Dick
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I have added the upper bank to the galley. The foot rests can be seen. Note that there will be a cutout in the central deck to allow the mast to be disconnected from the histopede (the upright on the keel plank to which the mast is lashed and to be tilted down onto the crutch (histodoke). The yard could then be furled and stored. The more I think about it the more sense there is in an upper and a lower bank of rowers. It would mean there are two teams which could row in shifts . When a maximum effort is required, both teams could row. When storming a beach , the lower rowers could row onto the beach while the upper team gets into their armour and weapons and prepare to attack or repel boarders Cheers Dick
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There is a basic problem with using the Mataro vessel as the basis for a model in that , although built by someone who had knowledge of contemporary shipbuilding techniques, he was building it for reasons that are foreign to us. This vessel was a votive object. That is to say, it was an object of art made to celebrate a religious event: a salvation, a conversion, or a simply as a form of thanksgiving. Maybe it was even commissioned by the catholic church, who knows? The completed work of art was presumably meant to be hung from the rafters of a church and viewed only from certain angles. It was of supreme disinterest to the builder to accurately depict a scaled down replica of an existing ship (something which obsesses us today but did not start to occur till the seventeenth century). What was required was an object which conveyed to the lay person the idea of "ship" without obsessionally replicating it. Consequently, the dimensions of these votive ships were distorted and unreliable, Such votive "ships" were not uncommon in european churches during the middle ages and, it is my belief, such "models" were copied by artists to depict the vessels of the time. A classic example is the series of depictions of carracks produced by the master WA which were clearly drawn from model ships. You have to wait for the Renaissance artists such as Carpaccio who drew from real ships to reduce the distortions. So, by all means use the Mataro as a guide but I would suggest that reproducing an"accurate" reproduction of a carrack is largely guesswork. Even the archaeological remains are fragmentary and to some degree distorted but still give the best information on construction techniques. I'll get out of your way now (homage to John Clarke, sadly missed). Dick
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I was strongly considering installing a steering oar on my mycenean galley rather than a quarter rudder. But this would not be likely in a Venetian round ship. Dick
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It looks rather like a bragozzo, which is venetian, although I think they had lug sails. Dick
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Yes. You can see some projecting planks on the after part of the hull over which the stern sleeve slides. The sewn ropes are just to hold the stern on and allow disassembly (see Khufu royal barge). The longitudinal internal stringers are for holding in the caulking . Dick
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The stern module has been attached. It is my contention that these war galleys may have been required to be transported over land (see the Gurob ship cart) as was done later in classical times over the isthmus of Corinth. So it would have been advantageous to be able to dissassemble the craft partly. Hence the stern module is designed to slide into place and be held by sewn ropes as was the case with egyptian vessels. Also seen here is the through-beam in the stern upon which the steering oar bore. This also is fixed by ropes. Cheers Dick
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Yes, its absurd to think that the mycenaeans were not aware of egyptian shipbuilding practices and used them. The method of attaching the stern module is also adapted from the Khufu barge. The flat bottom and beaching sled on the bow make bringing the boat ashore much safer. Dick
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Thanks, Steven. I had seen most of these "reconstructions" before but did not want to become influenced by them. As it is, they have reconstructed single banked galleys whereas I wish to produce an idea of how a double banked galley could be built keeping iin mind the materials available in the Bronze age. I have inserted the lower thwarts and made them integral with the vertical stanchions and the rowers' foot rests. I made a rough jig to ensure that all these Frames are uniform as they will be used to construct the upper rowing benches and central walkway The thwarts and stachions are lashed together as metal nails would not have been used. Note the ladder-like appearance produced by the vertical stanchions as seen in the pottery images from the time. The next step is firstly to make the curved stern and then I will be able to start on the longitudinal "wales" to which the upper benches will be attached Cheers Dick
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The frames and foothooks have been inserted. This gives resistance to twisting, The hull is surprisingly strong even without the frames. This shows the histopede to which the mast is lashed Dick
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For ease of reference for those interested, I have inserted an index of the build on page 1. Thanks to those who have supported this build. Cheers Dick😁
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The planking is complete although the caulking remains to be done. Note the construction at the after end which is in preparation for the stern module to be attached like a sleeve. Some reinforcement of the prow was necessary but this is not a true beak (which came later during the geometric period or Iron Age (maybe worth another model?). Dick
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I would suggest The Anatomy of the ship: the ships of Christopher Columbus by Xavier Pastor. Much of its Santa Maria is based on the Mataro Nave Dick
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The planking of the hull is complete except for the sheer plank and capping. I am debating how much internal framing is needed. I dont want the hull to be too heavy. The stern section will be made separately as a module which will be slotted onto the hull in a similar way to the Khufu barge (I have a cunning plan!). The plank joins internally will be sealed with ribbands (and presumably some water excluding substance available in the Mediterranean (?resin or pitch) Cheeers Dick
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