.
(Because then you get) less harmonious surface.
Please also note I have used the term "surface", as opposed to "curve".
.
Samuel 1650 – a Dutch mid-17th century trader
- Thread starter -Waldemar-
- Start date
- Watchers 11
(Because then you get) less harmonious surface.
Please also note I have used the term "surface", as opposed to "curve".
Often (in my opinion, very often) you see narrowing sweeps like the one above, which come from the dead wood with a slight curvature, gradually becoming more curved and stretching again towards the bilge arch.
So there are no circular arcs.
.
In my opinion, you have just shown a modern reconstruction, not a source plan. Can you demonstrate this with a period plan?.
.
In order to verify the soundness of the conceptual method found in terms of the correctness of the resulting shapes, a check in the form of waterlines and diagonal lines can and should be applied at the end of this (often iterative) process. To repeat – this step is for verification purposes only, and in no way can these lines be used to modify the shapes of the leading frames. Or, in other words, any modification of conceptual bends can only be done by historically appropriate methods, as shown above in this thread (and others).Apart from reverse engineering, the same applies to the design (meaning reconstruction) of ships of the period, i.e. from the era of the use of non-graphical or partly graphical methods.
.
The shape looks very familiar to me.
.
I am very happy that you (probably) like it. You are arguably the harshest critic/reviewer for me.I now have a great desire to tackle the Dutch 72-gun ship plan you kindly provided me with recently. Any news on its dating?
.
Haha, I had the impression that the clashes you had with other critics were much harsher than with me. 
I sent several letters to international contacts of which I hoped they could help me to some information about the drawing, but so far it has brought me nothing.
Sorry.
I sent several letters to international contacts of which I hoped they could help me to some information about the drawing, but so far it has brought me nothing.
Sorry.
.
I meant: in the category of substantive discussants . Returning for a moment to the placement of the master frame on the Samuel 1650, I forgot to specifically write at the proper time that it is primarily derived from the run of the wales as drawn on the documentation of that wreck. This is a rather easy element to measure on the wreck, so I assume no mistake was made in this. Besides, this particular placement of the master frame makes for a very harmonious structure with all the other pieces of this geometric puzzle, as can be seen in the diagrams.As for the Dutch 72-gun ship, I now provisionally date it to the period of the War of the League of Augsburg (1688–1697), in which ships of this particular class participated in a rather great numbers. Admittedly, 72-gun ships had already started to be built/used by the Third Anglo-Dutch War (1672–1674), yet, still in much smaller numbers, and the concave shape of the fashion piece does not quite fit into this earlier period. The specifics of the design rather rule out the 18th century, except perhaps the first two decades at the most.
.
.
.
First, it is probably worth using an example of tracing the stempost taken from van Yk's 1697 work, which demonstrates that geometric design methods were indeed used.
In the description to the engraving above, on page 58, there is a thorough explanation of how to obtain the circular curve of a stempost, knowing in advance the height and rake of the stempost; the final shape of the arc of the stempost being obtained with a compass. This could have been a normal compass for drawings made to scale, or a string compass for real scale tracing.
Indeed, as you point out, in many cases it would have been inconvenient or even impossible to use a radius and a compass. Particularly in such cases, the designer could easily measure on the drawing (or calculate mathematically if he was proficient in calculations) the so-called deflection arrow. After scaling it to the actual scale, he could use this value when collecting timbers, for making a working templates or for giving instructions to carpenters. To give a simple example: we want to buy 52 timbers with a length of 9 feet and a deflection (in the middle) of 1 foot.
In this way, the two approaches, the geometric and the practical, combine and complement each other in a harmonious, even essential way.
It occurred to me later that I could have shown this graphically by drawing a sketch explaining the essence of this conversion, but I no longer need to, as Martes has just pointed out an incredibly valuable album of ship drawings from the very early 18th century (about which in subsequent threads) which shows such a conversion, i.e. from design convention to carpentry convention, and in an extremely didactic way.
Briefly, the designer/draughtsman used the engineering/design convention to define the arc (that is, using the radius) and then converted a section of that arc to the 'carpentry convention', for the purpose of purchasing materials and as a guide for the carpenters to work with (that is, using the length of the timber and its bend/deflection).
.
I have been looking for Martes's posts, but no luck so far. This is for me what it is all about, because of the 'carpentry convention' as you call it. What I would like to see is an example. Why not taking the 134 foot pinas as a test case. You showed the basics of the design, but how exactly did the shipbuilder do the math? For me that is the link between the theoretical approach with sweeps e.a. and the shopping list.
.
I have to admit that Martes, by pointing me to this album, has completely ruined my immediate plans. It is a magnificent collection of ship designs, drawn up personally and collected by none other than the Russian ruler Peter I in the late 17th and early 18th centuries.
It's 'all there', and everything in there has state-of-the art status: deep-water capital ships, coastal shallow draft warships, auxiliary units (even including camels). Designs à la anglaise, designs à la hollandaise, designs based on the diagonals as praticed already in France, even a copy of a Danish design by Ole Judichær and plans of galleys of presumably Mediterranean origin, etc. And almost all in engineering, design convention.
What may interest you, at the moment I'm taking 'inventory' of a plan of a Dutch yacht that was designed in a quite analogous way to Witsen's pinas, i.e. featuring hard chine (only slightly softened). But above all, it's further evidence of the engineering way Dutch ships were designed and built in this era.
.