Waldemar

First, it should be said that the true line of greatest breadth was not drawn on the profile view or is invisible on the copy I am using. However, it could easily have been reconstructed thanks to the drawn profiles of the three frames in the original plan. This is the arc connecting the top of the sternpost to the quadrant point of the stempost, passing through the level of the greatest width of the frames. The accompanying drawing shows, in particular, the formation of the two quarter frames. The dashed lines show the successive positions of the futtock mould, moved vertically and horizontally according to the floor line coordinates, and then rotated to the point of contact with the arc of the greatest breadth. All the other frames in between the quarter frames could have been designed and constructed in exactly the same way, prior to their actual assembly into the hull under construction. The hollowing curves at the bottom of the frames have a rather careless character of quickly drawn single arcs to save time.

Okay. I guess all the design ambiguities have been recognised, despite the lack of appropriate commentary on this drawing in the manuscript. What follows is a reconstruction of the main frame, featuring two details that have not yet been recognised or convincingly explained in modern works on early English ship design. Firstly, the profile of the main frame in the drawing is slightly wider than the design breadth of the ship, but the quarter frames are already of normal width, in accordance with the plan view. The same phenomenon can be also observed in some other early ship draughts. This is due to the specifics of draughtsmanship and is a kind of a drawing convention. Tracing the frames in full-scale on the mould loft removes this inconsistency with the result of a 'normal' breadth. The second interesting detail is two adjacent arcs of the same radius. This is not a drawing mistake, as one of these arches is part of the floor timber (template) and the other is part of the futtock timber (template). This has to do with the conceptual method of shaping the profiles of the pre-designed frames very widespread in the Mediterranean. In this method, part of the frame profile was moved vertically and horizontally and then corrected by a slight rotation (fr. le trébuchement, span. joba). Baker must have learned this method during his Mediterranean travels and from Venetian immigrants. Ultimately, however, the method did not catch on in England, and no early English source work on shipbuilding describes this method.

No comparison. I am referring to the hull lines. You can immediately see the hand of a skilled boatbuilder. 🙂

And there is no need to wait. The geometric construction of the midship mould on page 35 of the manuscript has already been explained by Johnston Stephen in Mathew Baker and the Art of the Shipwright, 1994. It is different from the midship mould of the ship plan I am analysing, so it cannot be used in this reconstruction: Figure 3.6. Fragments, p. 35 (redrawn). The diagram is a simplified version of Baker’s drawing. There are many more inked and scribed lines in the original, as well as numbers for the calculation of areas. In this example of Baker’s procedures for drawing the midship mould, breadth and depth are given as 36ft and 16ft respectively. dg = 1/5 ed. With eh = dg, draw gh. Then draw ec, cutting gh at i. Through i draw mk perpendicular to ed; ek is the floor for this half of the mould. Mark point l on gh such that hl = 2/3 gh. The first centre n is on mk and has its arc passing through k and l. Extend line ln beyond n; the second centre o is found on this extended line and its arc sweeps from l to c. To find the third centre, first mark the other half of the floor with p. The third centre q is at the intersection of oc and pn (extended). Baker then draws the upper futtock in three different ways.

In fact, I already have the main frame from this plan worked out. But in this particular case things are both more interesting and more complicated than just drawing it out. You'll see. The point is also that I intend to do much more with this historic drawing than has been done in all the modern works to date.

Who came up with this strange hypothesis? And what details contained in the text of the manuscript concerning this particular plan do you have in mind?

Wayne, are you referring to the Baker's drawing I am currently analysing?

The next step is to recreate the lengthwise division of the hull for individual frames (room & space). The original division has not been made in an overly precise manner. However, for the aft section of the hull (i.e. behind the midship frame) the intended spacing had to be 1 foot 11 inches. For the fore section I have chosen the same spacing, but it is also possible to have a slightly different spacing where one of the lines coincides with the geometric start of the keel, as seen in the original drawing. Source works leave not the slightest doubt that the different spacing could have been used independently for the aft and fore sections of the hull. In practice, any rather small difference seemed to make little difference. It is also noteworthy that the division in both directions started not from the midship line, but from the corresponding surface of the floor timber. This means that the midship frame was to be made up of one floor timber and four futtocks, two to each side.

It seems that this observation is perfectly in line with what has been already written about hollowing curves (deadrise) in my thread on Sutherland's hull design methods. Luckily, no need to randomly guess at the particular method employed by Baker, as all the determining factors are already clearly seen on his draught itself.

Before we go any further, I am posting a corrected sketch of the one shown in my post #8. As it turned out, the rising line of the floor (i.e. that in the profile view) was also constructed as a single arc, from bow to stern. This meant that its tangent point with the keel line fell slightly behind the midship frame (shown on the sketch). Alternatively, when drawn as passing through the three points (on stempost, sternpost, keel/midship frame intersection), it slightly cut the keel line. In practice, however, there is little dimensional difference between those two variants. I have sometimes given two values when dimensioning the same element. The second value, given in brackets, is written on the original plan, and is usually not quite accurate. Now it is perfect.

Jaager, it is best to hold off formulating hypotheses and drawing conclusions until the reconstruction is complete, unless you are prepared for quite a surprise. Now it has to be said that this drawing, or generally the Baker's work, has little or nothing to do with the Dutch, but rather with someone else. But more about that later in this thread.

Thank you for your contribution, Mark. Obviously, I don't even have a chance to fill the gap left by the two scholars you mentioned, but I will try my best to at least give a decent technical interpretation of this one iconic plan.

Druxey, please have a look at the zoom below. My measurements show quite accurately 3 inches for the deadrise at this place.

This is followed by the guiding rails, extremely important for this method: those of the breadth and of the floor. These rails have been drawn in the original plan in the simplest possible way as arcs of circles. The height of both ends of the floor line is quite typical for the period. In the middle this line touches the keel. Despite this, it is clear from the midship frame profile featuring a deadrise, that this is a drawing mistake or just simplification. Surprisingly, the position of the midship frame does not coincide with the greatest width of the ship.

According to the most refined scale on the left-hand side of the drawing, the keel length (K) of the ship is 60 feet. The (design) hull breadth (B) is 24 feet. All dimensions are in feet, and in parentheses are given their proportions relating to other parts of the ship, as found in the most logical or expected way. The first step was to define the axial elements of the skeleton. The sketch is self-explanatory, except for the vertical of the stempost rake, which was made double to enable its drawing construction. The upper arc of the stempost is tangent to the lower arc in the point A, and passes through the point B.

Thank you again Wayne. Indeed, I have found most of these studies useful in my reconstructions. I now intend to actually analyze this particular plan by Baker using graphical methods. And no, there will be no comparisons to cod's heads and mackerel's tails in my reconstruction. 🙂

Thank you for your input Wayne, but this is why someone should finally do it, or at least attempt to.

Below is a reproduction of the oldest ship plan of English origin, taken from the manuscript Fragments of Ancient English Shipwrightry by Mathew Baker (British Archives). This drawing is widely reproduced and more or less extensively commented on in numerous modern publications, but so far I have not yet encountered a detailed analysis of it, especially by graphic means. The plan is attractive for at least two reasons: it is complete in the sense that it would have already enabled the construction of the ship's hull in full scale by shipwrights. Secondly, its historical potential is considerable, as it represents a method of design different from the methods known from the later English treatises and manuals such as Harriot ms, 'Newton' ms, anon. ms 1620, Bushnell and Deane ms. Apart from other considerations, this very plan is a further indication of where to look for the roots of the methods then creatively developed by English shipwrights. The drawing contains quite a few inaccuracies characteristic of hand drawing. Reproducing errors of this kind as well as a simple redrawing misses the point, so in the following reconstruction I will rather look for the intention of the designer, trying to find as many regularities, proportions and interrelationships as possible.

It must be done by manual correcting the longitudinal guides ends. This correction should start more or less equidistant from the posts to get decent results. Quite lengthy process, but perfectly possible. And, in a way, just like in real boatbuilding techniques.

Here's my method for clinker strakes. Actually, I have used its simpler variant, as my surfaces were much flatter and more or less vertical. It means that in step 4 I have made even dividing in vertical direction, and not along the frame profile. Consequently, in step 5 my cutting surfaces were horizontal, and not perpendicular to the surfaces to be cut. step 1: two frame surfaces, inner and outer step 2: frames created, outer surface left for the next steps step 3: outer surface offset by roughly the plank thickness step 4: dividing plan for both surfaces (must follow the run of the strakes set beforehand) step 5: creating cutting surfaces step 6: both surfaces split step 7: lofting the inner surfaces of the strakes step 8: inner surfaces of the strakes offset as solids step 9: (Boolean) cutting edges of the strakes (optionally) step 10: (Boolean) cutting of the frames

I think I know what is involved. It's the same with my model. It's just not possible to get the course of the strakes in such a way that they have a perfect course in every projection. But the same effect must have been in real ships.

Kevin, I am about to describe my method of shaping clinker planks, but need some time to prepare the accompanying graphics.

Pipes could in theory be the ideal tool, but in practice they generally do not work well. Those with a fixed radius can only produce rectangular boards, i.e. having parallel edges (not very useful as you know). And those with variable radii are usually generated by software with a less than acceptable shape that is very difficult or impossible to correct. Not a bad disaster. The most reliable method I've found so far is to divide the station/frame profiles by an equal number to get a run of planks. But not all the way through, as this usually has to be done segment by segment, with each segment covering only a few runs of planks. Alternatively, from one wale to another (externally) or from one deck to the next (internally). Still, quite a lot of manual adjustments are usually needed.

Kevin, your boats look gorgeous both painted and unpainted. When it comes to lofting planks in CAD, I find it the most difficult task to do on a regular/systematic basis. Relatively flat surfaces are easy, but with heavily convex shapes insurmountable complications arise. Some improvisation is then needed. Perhaps Tabycz would have something to say....

Better yet, please make it quick so I can peep how you'll handle the rigging. 🙂