Shipwright’s report – Tim Kirk

12 foot midships model

Since we returned to operations in the Longshed at the beginning of August we have continued training and preparation to begin the actual build of the ship.  Covid has restricted numbers working but we have been able to plank the lower half of the midships model on the port side, using oak from the ‘twisted’ log that we took delivery of in autumn 2019.  Jo Wood, David Turner and Dave Rowley completed the work, including testing two caulking methods – both known to have been used in Anglo-Saxon and Viking period ships. Both methods worked equally well, providing us with something of a conundrum as to which to apply in the ship.

A different team will complete the planking in order to broaden the skill-base within the Ship’s Crew.

The starboard side has been completed in mock-up by Mike Pratt and David Steptoe, using plywood and softwoods.  We are getting on with that so that we can begin the experimental part of the project – investigating the bio-mechanics of rowing the ship. Nothing is known of the internal structure and the rowing positions will have to be derived from various technical procedures.  Jacq Barnard is involving specialists from British Rowing to advise on this aspect of the build.

Oars

We now have one (prototype) oar, made using modern techniques from the ash received last spring from Suffolk Wildlife Trust.  We had to use power tools to shape this oar because the wood had seasoned, and hardened, during the lockdown.   Still, it is a work of art – thank you Simon Charlesworth.  Brian Hunt is constructing a second oar.

Keel and strakes

We have laid a false floor in the Longshed to rest the 12 metre keel log on, in preparation for working it and subsequent cleaving of the garboard strakes (the first planks of the hull).  We will work on the second, curved, log for the stem and stern and keel ends at a new site located at Hoo House Farm (a few miles from Woodbridge).  We have temporary use of a barn similar in size to the Longshed and much of the initial cutting and cleaving of logs will be done there.  We will bring the semi-finished components into to the Longshed for final finishing and assembly.

The supports and false floor ready for the keel log
1:5 model

This model is really important as a source of practical information for the full-size build.  John Cannon and Clive Cartmel have completed battening-out of the planking.  Doing so has raised issues with the layout of the planking – that’s one of the next problems to be solved.  But its much better to identify issues like that now than when we are working on the shipbuild with hefty full-size planks five times as big.

The 1:5 model battened up for planking

Next…

Research continues; very little information exists about Saxon-era anchors and mooring systems.  Vicky Fleming has written a very stimulating research paper on the subject.  Joe Startin continues to lead on our research and has gleaned nuggets of information from the folk at Nydam in Denmark.  I am excited to be writing the dissertation for my degree on the development of the side-rudder, with particular reference of the Sutton Hoo Ship.

The next stages of the build will focus on the conversion of the keel and its extensions (the ‘underlouts’), lofting of the sections of the ship and making the moulds to check the accuracy of the shape as we build.

Many thanks to all those involved and we hope that as we go forward we will again be able to involve more people in the build team. Apologies to anyone whose contribution has not been acknowledged – I really value all the contributions that you make.

Tim Kirk, Shipwright 5:11:20

 

Joe Startin speculates – did the Sutton Hoo ship sail?

Did the Sutton Hoo Ship buried in Mound 1 use a sail?  The conventional wisdom is reflected on the British Museum website. “….it is just not possible to tell if the ship had a mast and was sailed in the open sea, or if it just had oars for rowing along the coast and rivers.”

But the romance of sail is strong.  Edwin Gifford built a half-length replica, Sae Wylfing, to test some of his theories about sailing.  There is a famous (infamous?) picture of her creaming down the Deben taken by Cliff Hoppitt in 1994

Photo of Sae Wylfing on the Deben taken in 1994 (courtesy of Cliff Hoppitt)

Who would want to imagine things otherwise?  It seems unthinkable that the Anglo-Saxons would have been such spoilsports as to forego a mast.

The ‘sailing’ I am thinking of uses a sizeable mast and a big sail.  And it is more than allowing the wind to puff you along from behind.  To be a regular, practical option, you must be able to sail when the wind comes from the side too – you must be able to ‘reach’.There is nothing convincing in the written record to say whether the early Anglo-Saxons were sailing or not, let alone what our particular ship was doing. Scandinavians have plenty of evidence to show that they made brilliant use of sail from about 800CE onwards.  How and when they got to that state is the subject of endless debate.  There is some indication of earlier prowess in pictures carved on standing stones on the Baltic island of Gotland.

Fragment of a standing stone from Gotland

A simple sail, using sheets (ropes) at the corners, starts to appear around 500 or 600, depending on who you believe. The sea-faring kingdom of Dál Riata, covering the NE tip of Ireland, the Inner Hebrides, and the adjacent Scottish coast, was flourishing around 600CE.  Their naval ships were ‘seven benchers’, with two men to each oar.  But they are also said to have had a mast and a single sail as well with 28 rowers.  Alas, Dál Riatans would not have had the slightest contact with East Anglia until Irish missionaries started arriving in the 630s.

There is a strong motivation for merchants to use sail.  If they can turn up somewhere with rare and attractive goods, they might make a killing.  They cannot afford to pay and feed lots of rowers, but they are prepared to hang around waiting for a fair wind.  A shortish, tough, beamy old tub would do for a ship, so long as it could get there.

In the middle of the 6th century, the overland trade route from Byzantium to Scandinavia was interrupted.  Goods went instead via the mouth of the Rhine, and along the coast, through the Wadden Sea, to Jutland and onwards.  The trade grew, becoming dominated by the Frisians.  Emporia (trading settlements) sprouted on the continental side, and had counterparts on the English side too, not least in Ipswich – “England’s oldest  continuously inhabited town” – from about 600CE.

I think sailing would have been around in Raedwald’s time, if only for trade.  And anyway, it would be odd if it had been completely forgotten since the Romans left for good in 410CE.

To be continued…..

Joe Startin

Reflections on creating the keel for our ship

Building this great ship starts with construction of the keel.  What did we need to look for when identifying suitable trees?

The key point is that finding a straight, and nearly flawless, oak for the thin plank keel is a huge challenge in England today as we have no wildwood.  Damian Goodburn advised that “Even in early Anglo-Saxon times after intensive Roman use of the woodlands for 350 years this would have been a big challenge.  It might have been easier later once the wildwood spread out further, until the 13th century in southern England.”

A deeper section of keel that could accommodate some knots would make the challenge a little easier, but this is not an option.  That’s because we are constructing a ship that does not just exist in the Shipwright’s head.  Our aim is to build a ship that is as near as possible to the original ship that was buried at Sutton Hoo, and we are working to a plan that’s based on what was found in the burial mound. The evidence from the burial mound is that the original ship had the shallowest keel imaginable, as you can see from this cross section of a (rather smart) model that Damian made for the original exhibition at Sutton Hoo.

Photo of the model made for the NT exhibition at Sutton Hoo showing the T shaped keel section

The keel is the T shaped section in the middle of this photo.  It is a slight thing, but it beautifully reflects the evolution of shipbuilding, from rafts, through hollowed-out logs, to hollowed out logs with planks attached at the sides to deepen the vessel, to a plank as the keel…  The keel may be slight but it is a lot more sophisticated and allows the ship to grounded without damage.  What extra strength it has over a plank isn’t clear – our ship probably flexed a good deal.  The strength to keep its shape also came from the thwarts – 26 cross pieces that it was probably possible to sit on whilst rowing.

Our keel hunters have found a beautiful, straight grained and knot free tree.  Although finding something in southern England long enough didn’t seem likely at one stage.  Even so, whilst the keel needs to be straight, the stem and stern just aren’t.  Luckily we also found a tree with a curved trunk that looks like it will fit the bill.   Damian has provided a practical solution as to what to do to make the best of our lovely straight log and the curved one as well.

“I suggest that the practice attested in later Viking longships and later medieval clinker vessels be uses, that is a keel with two linking pieces – ‘lots’ or ‘underlouts’, and stems above each underlout.  That is the main keel of about 10-11 metres with enough for scarfs each end be scarfed to more ‘v’ shaped and curved underlouts at each end about 6 metres long which are then also scarfed to the main upper stem timbers above them around 6.5 metres long.  This approach could be adapted to the actual timber obtained and adjusted as  required – though symmetry was likely.  The scarf locations would also be bridged by garboards and other bottom planking.”

For those who aren’t boatbuilders or maritime archaeologists, this means:  at the end of the straight bit of keel under the ship, the gentle curve upwards is produced by joining the keel first to one (underlout) then another, curved piece.  The overlapping joints at the end of the keel and between the two curved bits are the scarfs – as you can see the scarf joint at point F in the photo below.

This image showing an imagined scarf joint (point F) is from drawings made in 1975 following the second excavation of the burial mound. (If the scarf had been made this way round it could have ripped open when the boat grounded)

And the garboards are the first planks that make up the bottom, then the sides of the vessel.  You can see them in the first photograph (of Damian’s model).

Damian again: “All the parent timbers found have to be cut out well over length ie 12-14 metres for the keel and about 7 metres, with appropriate curves, including scarfs for the underlout and stem logs.  As the late Saxon Graveney boat has a stern post made from half a log and this – two stems from one curved log approach – was widely used in practice in later medieval vessels, I would suggest that each selected log be divided in two, length-ways, by sawing and then hewn into shape with Saxon style axes.”

There is an element of revolution in that advice.  Damian is suggesting that we use saws for some of the processes and finish the work with traditional hand tools.  The heresy is to saw the logs but he makes the suggestion with good reason:

“The Anglo-Saxons did not have saws of any size.  But I personally think that splitting the log for the keel is unrealistic and could be enormously time consuming as defects in the chosen log’s grain might make each log half unusable and in large timbers the defects could be hidden inside the parent logs until too late.  Roskilde (our colleagues at the Viking Ship Museum in Denmark) have already shown that this is a perennial problem for keels and stems in early clinker vessels that are made without any sawing length-ways.”

So the point is, that you could do a huge amount of work and up with a keel shaped piece of wood that is totally unfit for purpose and in essence wasted.  A whole oak gone for nothing.  We cannot risk that.  Following Damian’s advice we will record the sawing for display and publication as a technical compromise.  Shaping the best keel slab with Anglo-Saxon tools will still be a great spectacle and a huge challenge.

So, how do we think that using a non-traditional method as part of the construction affects the project?  Is it still and authentic reception of the Sutton Hoo King’s Ship?  Our overwhelming answer is – yes, it will still be authentic.  Using sawn timber to construct the keel will not affect the weight, the strength or the appearance of the ship, and very importantly, will not impact on the validity of sea trials.  It will reduce time and expense, as well as probably saving us from wasting trees.  There are other obvious compromises that we have already accepted: did the Anglo-Saxons build indoors on a concrete floor?  Did the fell their trees with chain saws?  Were their labourers volunteers, and did they have protective equipment?

We can’t conceive of all the problems that the Anglo-Saxons overcame in building their King’s Ship.   Adopting the practical compromises that we are choosing to make just leaves us all the more in awe of what they achieved.

 

 

Why are we using green oak to build the Ship?

We often get asked why we are using green oak to build the Ship and why we are (where practicable) using ancient techniques.  Here, Dr Damian Goodburn who knows much, much more about medieval oak than most people,  provides us with many reasons why we should do so.  The photo above shows Damian using a side axe.

“Simply put, green logs and roughed out timbers are very, very much easier to work with human muscles than partially, or totally seasoned timbers – especially using simple hand tools, such as axes.  This is probably principally why it was used in such a green state.  And there is much evidence for the use of green timber in the early medieval period for ship building (including from Sutton Hoo and large scale woodwork elsewhere) – and no evidence against it.

Experiment and experience shows that if the surfaces of the timber are worked green an axe-finished surface is smooth with little or no tearing of the grain, with widely spaced axe marks.  Well-preserved surfaces on early medieval boat timbers and other heavy woodwork show a smoothness that would fit with this. The impression that the Sutton Hoo Ship left in the ground was entirely smooth.  Where second-hand seasoned timbers are re-used and refinished, because of the comparative hardness of dry oak the tool marks are much rougher and closer together.

Fragment of the Bayeux Tapestry, with edging, showing the construction of ships for William the Conqueror. (Classic image/Alamy Stock photo)

Historical sources from the end of the early medieval period, and images such as the Bayeux tapestry, and other embroidery, show that timber was worked on in the woods where it was felled.  This implies rapid, green roughing out at the very least.

Later medieval ship and boatyard excavations also show roughed out timbers arrived in the yards in freshly felled condition with some work having been done at the felling sites.  The lack of drying shakes (cracks running through the timber) or any marked decay supports this – though in a few cases there was also some re-use of second-hand timber taken from earlier vessels.

Systematic tree ring dating studies of early medieval woodwork and boat timbers (all a little later than the ship burial at Sutton Hoo) show very little evidence of stock piling timbers for seasoning.  Where we do have historical dates for medieval buildings and vessels made largely or entirely of oak, for the vast majority of timbers evidence from tree-rings shows that felling was usually only shortly before the recorded date of construction.

A quick turnaround – using green rather than seasoned oak – has benefits from an economic perspective, and to avoid timber degradation from drying shakes, rot or insect decay.  Degradation is less problematic when timbers are worked into smaller sections.

In reality the terms seasoned versus green are rather misleading extremes, even today.  We might accept oak as ‘seasoned’ when moisture content is down to about 20%  or less, whereas green oak has much more moisture-sap in it.  In the early medieval period totally seasoned timber (other than second hand material) is likely to have been a rarity and for use in small high status items.

Wet storage inhibits decay and slows down any hardening before finishing.  Some strands of archaeological evidence suggest that early medieval boat and ship builders in NW Europe were well aware of the issue of controlling seasoning. There is evidence of wet-stored rough out timbers such as the Eigg stem.  Very acid bog water or salt water would probably be best.

One of Damian’s sketches illustrating different log sections

Splitting before use may reduce drying distortion.  Radial cleaving, ie splitting the trunk across the diameter then again across the radius of each piece, produces the greatest natural strength in planks. A tangential split, ie splitting off a piece not directly across the diameter is less strong.  We believe that the Anglo-Saxons did not have saws of any size (unlike the Romans or later the Vikings) so splitting using one of these methods would have been used to produce planks.  The cleft plank would be finished (hewn) nicely with side axes.

A close look at the Bayeux embroidery shipbuilding scenes shows that the roughed out cleft boards were put up in the tree crotches to dry after splitting.  This suggests partial rapid drying of those thin hull boards.  This can only achieved without massive distortion and splitting using radially cleft boards (not tangentially cleft and hewn or sawn planks).  Oak that has been converted into boards the ancient way using radial cleaving shrinks much less (about 50%) because of the way the timber is structured.  Splitting and distortion is also limited.

Partial drying, when the wood is still relatively green, also has the advantage of making bending easier. Think of bending a fresh stick of celery compared with a slightly wilted one – the latter is much easier, but the celery is still green.  With the easy lines and gentle bends of the Sutton Hoo Ship this is only of academic interest – it probably wouldn’t have been an issue.”

Getting it into perspective

You remember those tricks of perspective, like the line with arrowheads at the end facing inward that looked shorter than the line with arrowheads at the end pointing outwards?  And the drawing that either looked like a vase or two people facing each other – but you couldn’t see both things at once?  Well, the Saxon ship is so big – and so much bigger than Sae Wylfing – that you’ll need to stand some distance away from it to just grasp the enormous scale. 

 

We love Sae Wylfing but in truth it is only one eighth the size of the real McCoy.  Half length yes, but also half the width and half the height.  Which makes perspective a bit odd when it is filled with rowers who are not one eighth man (or woman) sized.  So it’s going to be worth waiting for the real McCoy (although I can’t think of a worse name for it!); it’s going to be so long that when it is launched for the first time the bow will look as if it’s  half way across the river at Woodbridge before the stern hits the water.

 

Size is everything

The life size banner of the Anglo Saxon Ship has been put up in The Longshed. This shows the true perspective and enormity of the building project.

Paul Constantine, of The Sutton Hoo Ships Company, can be seen standing in front of the mid section to give an indication of the height.