Medieval Spanish Coca - AMATI 1:60 [COMPLETED BUILD]

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Medieval Spanish Coca - AMATI 1:60

Greetings to all the shipbuilders in this forum.

October 2019 I decided to do another attempt in shipbuilding (the first was the Golden Star when I was a boy) and I chose the AMATI's Coca, because:
1) she's very nice and
2) she seems easy (but I realized it wasn't so for me, maybe for other people more skilful).
3) it's not a very common subject.
100_1550.JPG
One negative aspect is that the documentation about 15th-century ships is very scarce. Actually, as an example, no one knows exactly how the Santa Maria of Columbus was built, which is also more recent.

After examining the plans and looking for images of contemporary boats, I decided to make some changes:

beta.jpg
1) the hawseholes must be moved forward.
2) the yellow marked area will be "clinker working".
3) the upper beams will have a smaller section, differently positioned and will be more numerous.
4) the lower beams will be more numerous and differently positioned.
5) some wales will be differently positioned and one more (5) will be added.
6) the frames and the bulwark stanchions will be more numerous.
8) stern deck extended (in yellow).
7) the rigging will be totally changed, following that of the Nao of Matarò at:


The Nao of Matarò is considered the forerunner of all constructions of this type, even if it was an ex-voto and perhaps not a faithful model of the prototype.

See you soon,

Rodolfo
 
This will be a very interesting building log - I am sitting in the first row
 
Thank you, friends, for your interest.
I hope I won't disappoint you.
I am now binding the yard to the mast, so I have to go back to the past with the pictures and try to follow a logical thread.
The material inside the package is of good quality; the blocks in my opinion are not suitable for this ship, but for more recent ships and on a scale of perhaps 1/100.
The instructions are clear and well detailed. Overall I am quite happy with my purchase. Obviously, if you are seeking maximum historical fidelity, you have to make any changes to the original design which, being an industrial project, is affected by many simplifications.
The frame is composed of very precise pre-cut parts; I needed only a few thin thicknesses to definitely stop the joints of the frames:

prima.jpg

The assembling of the structure is very easy and we can skip its description.
After glueing frames and fills to the keel, it is time to insert the lower beams 5X5 mm. I started following the instructions and after I modified them. It is also possible, however, to prepare the seats in the keel beforehand for their final arrangement.

After the lower beams, it is time to glue the plywood that will support the main deck. It consists of two pieces, left and right. I couldn't fit the two pieces so I divided them in half perpendicularly to the keel. The cut must fall on the top of a frame, to support and glue the edges. When glueing, it is important to press the plywood firmly onto the frames, especially in the middle, in order to avoid the cusp that may be formed along the joined edges. The main deck can then be surfaced with sandpaper and covered with the suitable strips.

Cocca-AMATI-1-struttura.jpg
The strips must be cut to a length specified in the instructions. However, make sure that you do not end up with too short strips near the deck openings: in such cases, it is better to leave them longer. I learned it too late, as you can see near the opening for the main deckhouse.
I have tried different types of nailing, but have regretted it. If I could start again I wouldn't attempt it. Perhaps a dot made with a very sharp pencil would be acceptable, or very thin copper or brass wires inserted vertically and then sand-papered.

The work continues... see you next time!
Rodolfo
 
Here we are!
In the previous picture, the portside wall has been glued to the frames along the deck edge in contact with the beams. Now all the plywood sidewalls are glued to the frames and deck:

fianco sinistro.JPGfianco destro.JPG

The lines are drawn in pencil to mark the limit to which the upper beams, 3 - 3.5 mm square, will be fixed.
As they must be aligned with the existing beams in the frames, it is natural that they should be placed close to the top line.
The next steps will be to glue the waterway (not planned in the project) all along with the hull, to cover the bulwark inside with 1x4 mm walnut strips, to add some bulwark stanchions and to plank with walnut strips (0,5x8mm) the visible side of the frame (visible from the bow and the stern)

Ponte poppa 1.pngponte prua 1.JPG000_3939.JPG

Cocca mediterranea 30122019 025.JPG

This is the side towards the bow, with some added stanchions bulwark and the planking of the wall and the visible side of the frames.

See you soon!

Rodolfo
 
Dear all,
here are two images (among many others) that inspired me. Unfortunately, in the beginning, I used to collect everything I found in a rather disordered way and now I don't know the exact sources (very often Pinterest).
f36d7743205bc5d7ef23eceebf2ac5ec.jpgordinate in vista 2.png

Anyway, you can see the different size and position of the high and low beams; it's clear also the most advanced position of hawse holes. The greater number of visible ordinates is also evident in the following image:
struttura nao.jpg
Looking towards the bow, we make the holes for the hawse-holes and the previous ones will be closed; obviously, the holes must be not under the main deck :

fianco sinistro.JPG occhio di cubìa.JPG

See you soon!
Rodolfo


 
Don't shoot me, but the ratlines in the first drawing of you're last post are incorrect. In these years they didn't had ratlines, they came somewhere in 1550 or so on the ships. In those days before that time they use a rope ladder to climb to the top of the mast. (Source R.C.Anderson) Please correct me if I'm wrong.
 
Hi Stephan,
I've already prepared the "Jakob's ladder"! ;)

100_1578.JPG

Anyway, the "Nao of Matarò" doesn't have the ratlines (neither the rope ladder, but nearly six centuries have passed and it has undergone numerous alterations). Therefore I won't be using ratlines either on my ship.
I've studied the problem and it seems ratlines could be older, before 1550. As an example, Xavier Pastor in his marvellous book "Anatomy Of The Ship -The Ships of Christopher Columbus" wrote on page 15: << Ratlines placed on the mainmast shrouds are based on early sources such as the seal of the City of Danzig (dating from 1400)>>.

I've also found some interesting drawings in the wonderful book of Heinrich Winter "The ships of Columbus":
1) The ships of Modon (today Mothoni, in Greece), from a codex of 1486 :
100_1581.JPG 100_1586.JPG

2) a Spanish gold medal of XV century, now in Madrid:100_1580.JPG

3) Altarpiece of "Saint Ursula and eleven thousand virgins" by Joan Reixach (1411-1486), Spanish painter and miniaturist. Dated 15th century:
100_1584.JPG The man cannot climb a rope ladder; the ratlines are just omitted, as are the port shrouds for artistic reasons, of visibility, I suppose.​

4) Finally, the 'Demonic Ships' by François de Cologne in the church of St Nicholas in Burgos (1505):
100_1582.JPG 100_1583.JPG

The first has the ratlines, the second seems to have a rope ladder, even if it's difficult to understand where the sailor will place his right foot...maybe ratlines were erased?

Looking at all this documentation, made me think that it would not be wrong to apply ratlines even before 1500.

See you soon!

Rodolfo
 
Nice research.
And indeed ratlines. That makes the literature inaccurate. There is a lot unknown about rigging in the old days. That was something I discovered first.
 
Last edited:
Hi Stephan
Unfortunately, before 1500 technical documentation is very scarce, builders worked by eye, there were no plans and drawings (I suppose) and no one was interested in transmitting the description of things that were normal at that time and they thought were uninteresting. So we have to look in other areas to get some ideas and develop hypotheses...
Anyway, going back to our Cocca, we have seen that the number of frames is higher than the one set by the manufacturer.
A couple of false frames has already been added to the bow (see post #5).
At the stern, we've also some additional beams that must be added, in order to arrive at a similar structure:

c.jpg

As a consequence, some other false frames must be glued under them. Here the holes for the upper beams have been prepared (3x3 or 3.5x3.5 mm; also 4x4 if other sizes are unavailable):

b.jpg

In this way, we can achieve greater precision in insertng the false frames; the new beam is only inserted, not yet glued:
FINTE ORDINATE.JPG
For bending the strips after soaking them in water:

100_9887.JPG

Here the false frames (made in walnut) have been positioned; in addition, the visible part of the former frames and beams has been covered with a thin walnut veneer:
m.JPG

A particular detail not included in the plan, but visible in many illustrations:n.JPG

h.jpgi.jpg

It must be inserted before covering with the upper deck.

See you later!

Rodolfo



 
Very interesting build Rodolfo. You are doing thorough research it seems.
 
Thank you Heinrich,
after sixty years of model railroading, I didn't think I would find a universe as immense as the history and technology of ships.
But it's only natural because trains have only existed for two hundred years, while ships are as old as mankind.

Now, beams of smaller cross-section and larger numbers are added in place of some of the original ones. This photo shows their position:
a.jpg

False upper deck beam hanging knees have been glued underneath the beams (yellow arrow), to conform with the existing ones:

b.jpg c.jpg

The new beams are more bent than the previous ones, and the deck above them will rest on them. The pre-existing beams are not a disturbance and can remain where they are:​

d.jpg


Now the false plywood deck is laid and a support is added to help support the rack:

e.jpg f.jpg

Laying of the upper deck (to be covered in future) and of the waterways (detail not included in the instructions, but highly probable):h.jpgi.jpg

The Bulwarks are then planked with pieces of walnut strips:

j.jpg
























Good work to all!

Rodolfo
 
Greetings to all forum friends!

we now glue two walnut strips 4x4 mm on the stern board wall; the upper must be bent like the deck:
k.jpg l.jpg m.jpg

As I wanted to insert a balcony, I glued another strip on top, to have a sufficient base to enlarge the glueing area:

n.jpg o.jpg

Now it is time to planking the deck, adding the false frames as a continuation of those below and to paint frames and bulwark:

r.jpg s.jpg

Now we can also cut the beams for the deck opening and build a border around the edge:

q.jpg

See you next time!

Rodolfo
 
Greetings to everyone!
Now we've to add the main rails. First I've added a strip up to the plank and then the plywood:

2.jpg aa.jpg

1.jpg a.jpg

3.jpg 4.jpg

The stern should now be refined. First the balcony under the deck and then the transom, a little different from the instructions:

dragante1.JPG dragante2.JPGdragante3.JPG dragante6.JPG
specchio di poppa 004.JPG specchio di poppa 021.JPG

x.jpg y.jpg

Next step: The lower beams.

See you later!

Rodolfo
 

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Dear all,
now we have to modify the arrangement of the lower beams. The preexisting ones will be cut flush with the frames and deck.
In the following images, the arrows indicate the added beams:
a.jpg b.jpg

View from above:
c.jpg d.jpg
Now we can start thinking about the first planking.
See you soon!

Rodolfo
 
That is absolutely superb and meticulous work Rodolfo. Not only is this ship a very interesting subject, but your scratch-building is just as innovative! Well done! :)
 
Thank you Heinrich, that's a great compliment for me.
Following the instructions, we have to lay the first planking, then the second and finally place the wales. Both plankings are made with pieces of the strip to simulate the real planks and the result is very nice::
b.jpg

In this way, the wales (glued afterwards) will not be flush with the adjacent planks:f.jpgd.jpg c.jpg

But in real practice, the wales were attached to the frames first and then the planking followed; we'll try to follow the real method in order to obtain this result: a.jpg

Beginning of the 1st planking with basswood laths:
The 4x2 mm strips are great for this work, they bend well on all sides and their thickness will make it possible to correct all imperfections with sandpaper. It is preferable to curve them both lengthwise and upward at the bow (more) and stern (less). The work will be easier if they are curved more than required because then they will be forced against the keel by keeping them pressed against the frames.
I soaked them overnight and then curved them with the iron of my wife on full power. Here is the result:
alfa.jpg beta.jpg

and this is the final result, with the remaining strips:
gamma.jpg

Towards the bow, it's preferable to put two shaped blocks of balsa wood to gently accompany the curvature of the strips, that would otherwise be more straight:

fasciame 049.JPG

That's enough for today...see you soon!

Rodolfo
 

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Hello everyone!
The first lath is glued leaning against the lower beams, at a constant distance from the bulwark, if possible. At the stern the strip ends leaning against the transom:

fasciame 032.JPGfasciame 043.JPGfasciame 045.JPGfasciame 049.JPG

It's very important to maintain as much symmetry as possible and getting off to a good start is the first step:

fasciame 051.JPGfasciame 053.JPG
For the filling strips between the beams, I chose another type of linden, lighter and wrinkled, to be fixed with a spacer to help maintain alignment:
fasciame 057.JPG fasciame 056.JPG

After that, we proceed by putting more strips towards the keel and always trying to maintain maximum symmetry; the first three courses of planking were not tapered:

fasciame 060.JPG fasciame 059.JPG

See you next post!

Rodolfo
 
Dear all,
it is physically impossible for each ordinate to have the same number of strips, even if we must do all the possible.1.jpg 2.jpg 3.jpg

Looking at the model from the bottom, it looks like the planking has a sinusoidal pattern, but looking at it from the side you can see that it's fine. It probably depends on the fact that the frames at the stern are wider than those at the bow:
4.jpg5.jpg

The work will continue...Bye!

Rodolfo
 
Fascinating to watch. This is a REALLY interesting and most innovative build. I am watching very carefully!
 
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