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Mathew Baker's early concept of ship hull design, ca. 1570


Waldemar
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Good Morning Waldemar;

 

You may find the following description of the construction of a mid-ship mould, by Matthew Baker, to be of use. This is from a contemporary document in the British Library, which I transcribed several years ago.

 

All the best,

 

Mark P

 

 

Matthew Baker How to draw Mid section MSW.pdf

 

Edited by Mark P
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Thank you very much, Mark. My guess is that this is an early document, as the form of master frame shown seems to be quite archaic. Especially the extreme tumblehome and the bulbous waist. On the other hand, the geometric construction is simple, indicating a later period. Anyway, I don't think there are any two master frames designed by Matthew Baker in the same way. Each has a different geometric construction.

 

By the way, better Mathew or Matthew in this case?

 

 

image.thumb.jpeg.256e39da2c5d6f86b1413ebf2c76e2ef.jpeg

 

 

Edited by Waldemar
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@Mark P

 

... almost forgot. It is possible that this document contains an anomaly (or maybe a transcription error?) – in the text description the half-breadth is 90, but in the drawing it is apparently 93, so I had to choose. And there are plenty of such anomalies in the Baker's drawing I am scrutinizing...

 

 

Edited by Waldemar
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Thanks Mark for checking, that was much helpful.

 

As another check (if of any value), I have also taken a look at the Mer Honour dimensions as given in the sources (beam 37, depth in hold 17). On the graphics below, her proportions are represented by the yellow rectangle. As it happens, the fit is much better with the design grid drawn according to the text.

 

All of which suggests that one should go by the numbers Baker has provided rather than his all too often inaccurate lines.

 

image.thumb.jpeg.4c9a9619e9c7007eb7654ef56dc81cd0.jpeg

 

 

Edited by Waldemar
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13 hours ago, Mark P said:

Good Morning Waldemar;

 

You may find the following description of the construction of a mid-ship mould, by Matthew Baker, to be of use. This is from a contemporary document in the British Library, which I transcribed several years ago.

 

All the best,

 

Mark P

 

 

 

 

Mark -

 

By any chance do you have the source information on this document? I am searching on the site but haven't come up with ths one just yet. Many Thanks!

 

 

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Another anomaly is shown below, which is difficult to interpret conclusively. Perhaps it is simply a Baker mistake?

 

Normally, design grid should be above deadrise. However, in this case, it is placed very unusually on the keel line.  But the frame contour falls almost perfectly 13 feet above deadrise! ... and it well may be that that this height was actually used to construct the shape of the master frame.

 

But how can this kind of inconsistency be credibly resolved!? Most likely, it also has to do with the incorrect run of the rising line of the floor, which should certainly not touch the keel.

 

image.thumb.jpeg.fc36748314959d13e84dbe8a0c6f553f.jpeg

 

 

Edited by Waldemar
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This is probably one of Baker's most confusing designs to guess at, further considering the inaccuracies of the original and copy and the absence of some working lines. So many traps here...

 

Yet, I think I have finally found the correct geometric construction of the master frame, although the outline of its contour has hardly changed from the previous iteration. The change is that the height of the floor, rather than the length, has been used to establish the extreme points of the floor. It is also important to note the key role of the inner design grid, with an aspect ratio of 2:1.

 

 

image.thumb.jpeg.8abcda80cbb639665d069b3468577af9.jpeg

 

 

Edited by Waldemar
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One consistent challenge in utilizing modern methods to reimagine old drawings is the urge to ignore the technological capabilities of the time.  A modern CAD program and basic calculator bring levels of precision and accuracy unattainable to the contemporary worker.

 

Using Baker as an example, a large part of his manuscript us concerned with finding the best proportions to allow the scaling of the midship mould from one tunnage vessel to another. The math was teduous - logarithms were not available until after Wells had assumed responsibility for the manuscript around 1600ish.

 

Interpreting this drawing as somehow flawed ignores the history of the item and the intended use. It is a scale representation, but not a construction drawing. It was most likely not intended to be 100% accurate but rather illustrative of the process.

 

I think the important question is whether using the modern tools, one can create the shape by replicating the radii of the arcs as described by Baker, then if these arcs can be adjusted using the rising and narrowing lines to derive other frames fore and aft.

 

Lastly, what where the proportions used in this specific drawing to establish the radii? As I recall, in some instances they were not mathematical but geometric points, unlike the 1620 MS where tge radii were a mathematical derivation of some dimension.

 

 

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1 hour ago, trippwj said:

One consistent challenge in utilizing modern methods to reimagine old drawings is the urge to ignore the technological capabilities of the time.  A modern CAD program and basic calculator bring levels of precision and accuracy unattainable to the contemporary worker.

 

Using Baker as an example, a large part of his manuscript us concerned with finding the best proportions to allow the scaling of the midship mould from one tunnage vessel to another. The math was teduous - logarithms were not available until after Wells had assumed responsibility for the manuscript around 1600ish.

 

Interpreting this drawing as somehow flawed ignores the history of the item and the intended use. It is a scale representation, but not a construction drawing. It was most likely not intended to be 100% accurate but rather illustrative of the process.

 

I think the important question is whether using the modern tools, one can create the shape by replicating the radii of the arcs as described by Baker, then if these arcs can be adjusted using the rising and narrowing lines to derive other frames fore and aft.

 

Lastly, what where the proportions used in this specific drawing to establish the radii? As I recall, in some instances they were not mathematical but geometric points, unlike the 1620 MS where tge radii were a mathematical derivation of some dimension.

 

Wayne, you clearly do not understand the essence of this project. To find the proportions, you first have to find the values that are not written in the drawing (also, read the last paragraph in my post #1). They have to be reproduced by graphical means in this case, and idle, demagogic talk doesn't help. If you want to do it by hand, be my guest, I prefer the computer as a working tool.

 

I am fully aware of the drawing techniques used at the time. And I was the one who had to explain to you not so long ago that arcs with many feet radii were not drawn on plans with a compass, but with other devices.

 

You are also contradicting yourself. First you suggest that the old drawings could not have been accurate, and then you smoothly accuse me of taking this circumstance into account while examining these drawings.

 

Finally, for your information, sometimes the dimensions were the result of an intentional application of some proportions and rules, but sometimes as a result of arbitrary choices.

 

Wayne, is there anything else I can explain to you?

 

 

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You assume a distance of the stern post overhang using an estimated overall  85' 0", or a measured 6' 9". The ratio of 6' 9" to 18' 0" is very close to 1:2.5 which is what I suspect Baker used in his construction. That angle produced by that ratio is 22 degrees. See how that fits, Waldemar.

Edited by druxey
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56 minutes ago, Waldemar said:

 

 

Wayne, you clearly do not understand the essence of this project. To find the proportions, you first have to find the values that are not written in the drawing (also, read the last paragraph in my post #1). They have to be reproduced by graphical means in this case, and idle, demagogic talk doesn't help. If you want to do it by hand, be my guest, I prefer the computer as a working tool.

 

I am fully aware of the drawing techniques used at the time. And I was the one who had to explain to you not so long ago that arcs with many feet radii were not drawn on plans with a compass, but with other devices.

 

You are also contradicting yourself. First you suggest that the old drawings could not have been accurate, and then you smoothly accuse me of taking this circumstance into account while examining these drawings.

 

Finally, for your information, sometimes the dimensions were the result of an intentional application of some proportions and rules, but sometimes as a result of arbitrary choices.

 

Wayne, is there anything else I can explain to you?

 

 

You are a tad aggressive there, sir.  You have not explained anything to me but rather argued why your view is correct. I am attempting to point out alternative explanations based on published works and theories which you disparage.

 

I am fully aware of the use of bows and splines, for example, yet the shipwright would still need to define that arc.  Just one example.

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30 minutes ago, trippwj said:

You are a tad aggressive there, sir.  You have not explained anything to me but rather argued why your view is correct. I am attempting to point out alternative explanations based on published works and theories which you disparage.

 

Wayne, just collecting bibliographic items may not be enough, but honestly good luck with your project. And I won't comment anymore on all the insinuations in your post. I'm simply wasting my time on it, aren't you?

 

🙂

 

 

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19 hours ago, druxey said:

You assume a distance of the stern post overhang using an estimated overall  85' 0", or a measured 6' 9". The ratio of 6' 9" to 18' 0" is very close to 1:2.5 which is what I suspect Baker used in his construction. That angle produced by that ratio is 22 degrees. See how that fits, Waldemar.

 

Rightly, this needs some clarification.

 

I have given the total length (i.e. between posts) of ca. 85 only as an indication of the overall size of the ship, so that others do not have to calculate or measure it anymore.

 

As for the stern, certainly both approaches were possible, though typically in early English texts the sternpost rake is given in degrees (in the range of 18–22.5 degrees). In this particular case, I'm pretty sure that the reading of 20.5 degrees is correct, but I've also included the graphic below for you to judge for yourself.

 

As for the bow, the reason for the actual lengthening of the keel by 0.30 (or to 60.80), remains open to interpretation. For now, I think it has to do with the value of 0.35, which I have also marked in the graphic below.

 

If the wale is drawn through the point at the stern and the quadrant point marked in the original drawing with a radius of 263 1/4, then its fit on the stempost is perfect, in contrast to the actual run of the line. This gives an idea of how draughts were then made in practice.

 

Overall, having now a better copy with more visible notations, a numerical approach can be better applied where possible.

 

image.thumb.jpeg.9ae63a8bcb21972b594072e665f4e685.jpeg

 

image.thumb.jpeg.55c270566a46a24f51b5d87abe29e4c4.jpeg

 

image.thumb.jpeg.8290168489ec4d6e6f58aeb8a6b67576.jpeg

 

 

Edited by Waldemar
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@Mark P

 

It was only later that I noticed that on the back of the document with the Mer Honour (Merhonour) master frame, the date 1600 appears.

 

This may mean that at this time English ships were still being designed and built using the Mediterranean (i.e. non-graphic) method as well, at least by Baker. Firstly, the contour of the master frame is built from the bottom up, precisely as in the Mediterranean methods, and secondly, its shape is not quite suitable for the hauling down/pulling up method known from the early English shipbuilding texts.

 

Such an interpretation can also be associated with the scanty number of surviving plans from the first decades of the 17th century, but this is perhaps more the domain of general historians...

 

 

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This was easy and quick to check, so below I still give the specific values of the sternpost rake as given in the early English texts, for comparison with Baker's drawing. 

 

Newton ms.: 18°–22.5°
anon. 1620 (Salisbury) ms.: 18°–22°
Harriot ms.: 22.5°

 

In general, I have tried to dimension and find proportions in such a way that those interested can easily make their own comparisons. Quite a lot of work has been put into it so far, and in fact the results may be needed mostly by those very few who make reconstruction plans today.

 

And I will say again that the greatest satisfaction for me was to discover the general method and some of its details that Baker used to construct this plan.

 

If one considers that in the early days the English hauling down/pulling up method was also at best only partly graphic, the almost total lack of plans from this period becomes more understandable.

 

 

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Comparisons of the more or less theoretical proportions of English ships of the period can be started with these two tables:

 

image.thumb.jpeg.d8bc0bbcc563a851229a6dc5579c4e25.jpeg

source: F. Howard, Sailing Ships of War 1400–1860, 1979, p. 96

 

 

image.thumb.jpeg.0d35108f2900a9c4419e1440e1620acf.jpeg

source: M. Bellamy, David Balfour and Early Modern Danish Ship Design, The Mariner's Mirror 2006, Vol. 92, No. 1, p.10

 

 

Enjoy

 

 

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I'm sorry to say that your post #75 and #78 to Wayne is, to put it charitably, unkind. Perhaps - assuming that English is your second language - you did not intend it to be a sharp as it reads, but that is the way I took it. Please be more careful. I take this thread to be an academic exercise of enquiry for respectful discussion. 

 

Now, I've looked at your range of stern post rakes and find that 18 degrees has a ratio of 1:3, and 22.5 degrees is 1:2.5 within experimental limits. I still think that you might consider the validity of constructing angles by ratio.

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2 hours ago, druxey said:

I'm sorry to say that your post #75 and #78 to Wayne is, to put it charitably, unkind. Perhaps - assuming that English is your second language - you did not intend it to be a sharp as it reads, but that is the way I took it. Please be more careful. I take this thread to be an academic exercise of enquiry for respectful discussion. 

 

Well, I have long since come to terms with the idea that people have different views, priorities and follow different authorities. It does not bother me. But if someone wants to forbid me from thinking for myself, strenuously imposes their point of view, and finally tries to undermine the very essence of my efforts without any concrete arguments but only through rhetoric, I find it difficult indeed to tolerate. On the other hand, I am happy to befriend anyone who respects my pluralistic principles. He does not even need to apologise anymore for such unfortunate attempts, reasonable statements in the future will suffice.

 

 

2 hours ago, druxey said:

Now, I've looked at your range of stern post rakes and find that 18 degrees has a ratio of 1:3, and 22.5 degrees is 1:2.5 within experimental limits. I still think that you might consider the validity of constructing angles by ratio.


Yes, you may be absolutely right that this is indeed the real source of these angles. But in doing the dimensioning, I decided to be consistent with the convention used in the early texts, i.e. using degrees. I guess it is important to maintain such uniformity not only for comparisons, but also because these angles were also defined in other ways. For example, in Fernando Oliveira's text from the second half of the 16th century, the sternpost rake is defined as 1/7 of 90 degrees, or about 13 degrees. In addition, there is a rule in engineering that you don't close dimensional chains, or in other words, that you don't dimension one object in two different ways, and I try not to break it without good reasons.

 

Perhaps I should have written about all this on a regular basis, but then it would have created a text monster that is not inviting to read.

 

 

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I understand and thank you for your participation so far. Anyway, that's the end of it now. Maybe others will show their research inquisitiveness and make some interesting new discoveries or findings.

 

Specifically, I would suggest here, for example, an examination of the 16th century wreck of the Basque whaler San Juan from Red Bay in terms of the conceptual method used, with particular reference to the Mediterranean method. 

 

Thank you,
Waldemar Gurgul

 

 

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Nolens volens, one more item of the utmost conceptual significance has yet to be clarified. In passing, as it were, the question of the apparent lack of deadrise is also clarified, as well as Baker's working methods themselves revealed. Specifically, it concerns the manner in which the run of the rising line of the floor has been determined (green arc on the graphics below).

 

Most probably, in the first instance, the height of this line aft was set at about half the height of the sternpost, which is a fairly typical value for the era (see the sketch below for more details). Next, the height of this line at the bow was determined by taking a multiplier again close to half (specifically 5/9), which also appears to be quite standard for the period, judging from early manuals and contracts.

 

Baker then mathematically calculated the radius of this arc in a fairly precise manner, with the height of the deadrise (4") evidently taken into account. However, for some reason he actually drew this line in an inaccurate and also misleading way, i.e. as if he had forgotten about deadrise. Or perhaps he simply did not want to waste time setting up the adjustable curve-drawing device accurately, being content to record the accurate value of 117 feet on the drawing.

 

The rising line of the floor being the same radius both for the aft and fore part of the ship, it is also quite possible that it was only then that the stempost was drawn, and in such a way as to intersect the point marking the height of the rising line of the floor at the bow (see figure below). Which would at last explain quite neatly the rather complicated geometrical situation in this part of the plan.

 

image.thumb.jpeg.0752490e730e2b07e8afcf8d1cce3673.jpeg

 

image.thumb.jpeg.55ac984cb2cc8f6763902fa24c6a48d3.jpeg

 

image.thumb.jpeg.c1158f11f9af79bfa6e04e05012ca150.jpeg

 

image.thumb.jpeg.b7d2de98c553e49f6a7d6988652eff34.jpeg

 

 

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Interpretation of Baker's universal ship drawing would perhaps not be entirely complete without at least attempting to establish another issue of conceptually capital importance, namely the position of the two quarter frames. If the fore quarter frame is clearly located at the keel and stempost junction, how did Baker determine the position of the aft quarter frame?

 

Early Mediterranean shipbuilding texts use the term 'ferir' or 'fiero' to denote the distance of the two quarter frames from their respective posts. However, none of these texts specify this in sufficient detail and, in particular, which points on the posts were taken into account. The following interpretation explains how Baker might have done this and, within drawing tolerances, fits very well with the lines drawn by Baker's own hand.

 

First, the master frame was placed at 1/3 of the keel length. Then the horizontal distance between the master frame and the height of tuck was divided into five parts. At 2/5 from the sternpost, Baker placed the aft quarter frame.

 

As it happens, the value of the 'ferir' thus defined is the same for bow and stern.

 

image.thumb.jpeg.bcf19c6775c7f335ea5e24848011dc7e.jpeg

 

 

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