Round-tuck sterns in 15-17th centuries

[Martes]

Round vs. square tuck, an omnipresent issue that probably deserves a separate thread.

It should be stressed that the round tuck is in no way a new technology that appeared in England in the beginning of 17th century, and the square tuck is also in no way an obsolete technology that was eventually replaced. Both have their advantages and disadvantages and existed alongside each other for quite a long time, and in a sense - still do.

Alexander McKee in his book on Mary Rose mentions that she was initially built with a round tuck and only during her first rebuild the tuck was replaced with square one, as it was - at the time - considered better suited for mounting stern-facing battery.

Softwood-built frigates and even British royal yachts sported square-tuck sterns as late as during Napoleonic wars.

Apart from the Swedish ship Mars of 1563, mentioned here, whose wreck exhibits a relatively classical round tuck stern, there are several other depictions of ships with round tuck sterns alongside ships with square tucks, for example:

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File:Portuguese Carracks off a Rocky Coast.jpg - Wikipedia

en.wikipedia.org

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File:View of Amsterdam.JPG - Wikimedia Commons

commons.wikimedia.org

 

[Martes]

To summarize the differences between the tucks.

Round tuck:

+ Strong structure
+ Hydrodynamic form
- Difficult to implement
- Expensive and requires specific shape of timber

Square tuck:

+ Easy and cheaper to build
+ Offers less restrictive space for tuck-level battery (on carracks, mostly)
- May be hydrodynamically problematic, restricting flow to upper parts of the rudder
- Noted as being prone to leaks (especially at anchor) and difficult to caulk
- Vulnerable to stern-on fire and stoving under severe pressure of water

 

[-Waldemar-]

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An apt summary, many thanks. If you'll allow me, I'll add another disadvantage of square tuck sterns, namely the exposed cross sections of the planks, particularly destructive in the warm tropics.

Below is probably a fairly well-known photograph of a section of the wreck of Batavia 1628, with what appears to be a rather makeshift, but at the same time well-conceived and effective, attempt to remedy this very flaw by applying in a second, protective layer, the planks already suitably profiled, laid at least in the underwater part of the hull. Precisely so as to cover those exposed cross sections in the first layer, from which the damage most readily started (especially by the easy entry of harmful worms).

Photo taken from an excellent work by Wendy van Duivenvoorde – Dutch East India Company shipbuilding. The archaeological study of Batavia and other seventeenth-century VOC ships, 2015.

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[Roger Pellett]

I wonder if Alexander Mckee’s description of Mary Rose originally having a Round Tuck stern is a mistake? Instead, did he mean a round stern? The planking of a Round Stern fastens to the stern post. The planking of a Round Tuck Stern twists and is fastened to the wing transom. Round Stern carracks were the usual construction prior to introduction of the square stern.

Roger

 

[Martes]

Instead, did he mean a round stern? The planking of a Round Stern fastens to the stern post. The planking of a Round Tuck Stern twists and is fastened to the wing transom.

Both above images are dated around 1480-1490

 

[Roger Pellett]

I stand corrected!

Roger

 

[-Waldemar-]

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I was also going to post here a few more extant graphics of ships from the earlier periods, but quite by accident I came across an excellent quality reproduction of the Battle of the Île de Ré 1627 by Jaques Callot, depicting a fleet of English ships (reproduced in an equally excellent work by Peter Kirsch, Fireship. The Terror Weapon of the Age of Sail, 2009).

It is only now, with a sufficiently high quality reproduction, that I have noticed a detail previously overlooked, namely the additional, rather irregularly arranged planks (or maybe better: of unevenly arranged upper edges), laid in a more or less vertical position on the lower part of the square stern. This is not the kind of detail that an artist invents on the basis of artistic license, but rather shows an authentic feature of the ships.

At this point, somewhat tentatively, I interpret this detail as a kind of additional, rather makeshift cover for the lower part of the stern. This not entirely recognized problem with the square stern (maybe leaks?) must have been quite common, since this additional overlay occurs on the majority of visible ships. In these circumstances, it is reasonable to assume that the direct cause of the widespread reintroduction of the round tuck stern on English ships in those very years may have had some very specific reasons related to these additional shields visible in the illustration.

Or in other words: the ground for the general reintroduction of the round tuck stern was already well prepared for this reason.

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And a close-up of the ships' sterns.

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