Pomeranian Rahschlup 1846 by wefalck – 1/160 scale – single-masted Baltic trading vessel

[Keith Black]

 That's great work, Eberhard. Many a time I've wished you and your milling machine were sitting next to me when tackling small pieces. 

[wefalck]

… but we are sinking slowly into technological obsolescence, considering what can be done with 3D-printing already.

[Keith Black]

56 minutes ago, wefalck said:

… but we are sinking slowly into technological obsolescence, considering what can be done with 3D-printing already.

 Sure but... I've got nothing against 3D printing. I buy 3D parts but I wish I didn't have to, I wish I could make those parts myself. I think there's something to said for building a model totally by hand. I can't do it but for those that can, I admire them and their skills greatly.  

[BANYAN]

Nice made parts Eberhard.  People may be able to buy them sure, but I only resort to that if the part required is beyond my skill level or capacity to make them.  A hand-made part is still preferable in my mind.

 

cheers

 

Pat

[wefalck]

I probably wouldn't buy-in someone elses parts, I was thinking of kitting myself out to do 3D-printing - or at least do the designs myself. On the other hand, as for my laser-cutting, parts usually do not turn out right at first shot. As @dafi knows well, there are usually several runs necessary to get the dimensions right for printing - unlike for substractive machining, where one in most cases ends up with the correct part.

 

However, I love this late 19th to mid-20th century manual technology of substractive machining and those old machines. In addition, I am already spending a good deal of my wake hours in front of a computer, so manual workshop work is a pleasant diversion.

 

[wefalck]

The shipyard had been closed for much of August, only the drawing office stayed open to prepare work for autumn ...

 

********************
 

Anchor-winch 4

 

The remaining item for the winch is the pawl-bit against which also the bowsprit rests. It is surprisingly thin, only 240 mm square, according to the original drawing, which conveniently translates to 1.5 mm on the model.

 

A strip a tad wider than 2 mm was cut from a scrap of 1.5 mm thick acrylic glass. Care was taken to cut it parallel to a manufacturing edge, which is clean and square. In this way, only one edge needed to be machined and the manufactured edge provided a good datum for this.

 

The pawl rest in a cast-iron U-shaped frame that is bolted to the front of the post (updating the design a bit from the older style wooden pawls drawn in the original drawing). Rather than adding this part to the post, I decided to mill it from the solid. Hence the 2 mm strip.

 

Originally, I intended to drill 0.15 mm holes for the axes of the pawls, but my drills turned out to be too short for that. This would not be really necessary at this scale anyway, but would have later, once a wire was inserted, facilitated the positioning of the pawls. I have to eyeball it now.

Milling the groove into the ‘cast-iron’ frame

 

The post was milled to size, letting material for the frame for the pawls standing. The shape of the frame was then milled out and the ends rounded with a safe-edge file. In the final machining step, the groove was cut.

Shaping the head of the pawl-bit

 

I don’t have square collets (I plan to make one day a set of square insert collets for precisely holding square stock), so a round one had to make do for the next operation, namely shaping the head of the pawl-bit with different burrs. Because of the relatively soft acrylic glass and with light cuts, this is not a problem.

 

Shaping the head of the pawl-bit

 

The pawls will be short lengths of 0.2 mm x 1 mm styrene strips, but will be made only later, when everything comes together so as not to lose those tiny bits.

 

To be continued …

 

[wefalck]

Thank you very much for the continued interest in this project 👍🏻

 

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Developing the Rigging Warrant

 

It may seem strange to talk about the rigging warrant at this stage, but as much of the supporting fittings have to be reconstructed from sources and certain fittings, such as pin-rails or cleats, have to be put into place before painting, now is the time to develop at least an outline for it.

Spar-dimensions as per table on original drawing by Möller

 

The original drawings comprise a sail-plan and a spar-list with dimensions, which is a good start. However, as this is the builder’s and not a modeller’s plan, there are no details on the actual execution of the rig. These have to be reconstructed from sources from around the middle of the 19^th century, notably

 

BIDDLECOMBE, G. (1848): The Art of Rigging.- 155 p., Salem, Ma. (Reprint 1990 by Dover Publication, New York).

 

BOBRIK, E. (1848): Handbuch der praktischen Seefahrtskunde, Schiffgebäudekunde, Zurüstungskunde, Manövrierkunde, Ankerkunde, Tafeln zur Schifferkunde.- 604 p. + plates, Leipzig (reprint 1978 by Horst Hamecher, Kassel).

 

Costé, F.-A. (1829): Manuel de Gréement ou l’art d’équiper les vaisseaux et autres batimens de mer, de tout ce qui est nécessaire a leurs mouvements.-  282 p., tables, Paris (Dezauche).

 

Jaÿ, . (1860): Études sur le Greément d’après les réglement du 25 avril 1857, révisé en 1858.- Atlas du Génie Maritime, 2éme Serie, Annexe No. 1: 55 pl., Paris (Ministère de la Marine et des Colonies).

 

KIPPING, R. (1853): Rudimentary Treatise on Masting, Mast-Making, and Rigging of Ships.- 150 p., London (John Weale).

 

MIDDENDORF, F.L. (1903): Bemastung und Takelung der Schiffe.- 401 p., Kassel (reprint 1977 by Horst Hamecher). – this is a bit late, but has useful tables with dimensions of parts

 

While these works contain many useful tables and sometimes beautiful detailed drawings, I realised that they are of limited use for this project as they mainly deal with larger ships. Only occasionally they give information on rigging practice for single-masted vessels. In some cases information on the foremast and bowsprit/jibboom of topsail-schooner was useful, as their rigging layout is similar.  

 

The popular secondary literature on, e.g. British or French naval cutters, that have at a first glance a similar sail-plan, also is only of limited value, as they typically have a running bowsprit, and not a fixed one with jib-boom.

 

So, much had to be interpolated, also from secondary sources covering earlier or later periods.

 

I also studied numerous images of German, Danish, Swedish, and Norwegian sloops operating in the Baltic with respect to the arrangement of stays, shrouds, backstays, topmast-shrouds, -stays, -backstays, and the bowsprit/jibboom. A considerable variability in layouts was observed.

 

Although the models of sloops and topsail-schooners in the Altona Museum (Hamburg) were built and rigged at the turn of the 19^th to the 20^th century, the model builders included older professional riggers, who presumably were aware of the earlier practices. These models give a good overview of the variability of rigging layouts and the supporting structures at the hull and on the deck.

 

With this information it has been possible to develop a draft warrant for the standing and (part of) the running that will help to dimension and locate the necessary pin-rails, rigging cleats, bollards, etc.

Reconstructed dimensions for the standing rigging

Reconstructed dimensions for (part of) the running rigging

 

To be continued …

Edited Sunday at 05:39 PM by wefalck

[JacquesCousteau]

Nice research work! 

[archjofo]

Hello Eberhard,

I was a little surprised when I read that you also cited F. A. Coste as a source.
But, as always, excellent research.

[wefalck]

Johann, Costé has a number of tables at the end that give the proportions of different parts. However, they are mainly useful, I think, when you have to reconstruct a sail-plan from scratch. In my case, I had the original sail-plan and spar dimensions. In fact, much of the literature is concerned with the preferable proportions of the spars, which in my case is given in sufficient detail. 

 

For the dimensioning of the standing and running rigging I mainly worked from Biddlecombe, but compared his data with those from the other sources.

 

Edited Sunday at 05:50 PM by wefalck

[BANYAN]

I understand the problems you have experienced in establishing such a Rigging Warrant.  I was lucky enough to have that document but, as you have experienced, the implementation is a whole different issue.

 

Nice bit of research

 

Pat