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 👍🏻

 

**********************************

 

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 September 7 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 September 7 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

[wefalck]

Work was been interrupted again, this time by some business travel to Tallinn for a few days, where I had also the opportunity to visit the Estonian Maritime Museum. Unfortunately, I came back from there with a sort of bronchitis that bogged me down for a couple of weeks ...

 

Pin-rails

 

Another delay in actual shop-work was caused that I first had to work out were the pin-rails would go and how many pins they have to have to provide the necessary belaying points.

Drilling the pin-rails using the micro-mill as a coordinate drilling machine

 

The pin-rails are 2.2 mm wide strips cut from 0.8 mm thick acrylic sheet. The holes were drilled using the micro-milling machine as a coordinate drill to get the distances right. The outer edges of the pin-rails were rounded as can be seen on many prototype photographs. The inner edges were notched for the bulwark stanchions on the filing-machine.

Cutting the notches for the stanchions on the filing-machine

Cutting the notches for the stanchions on the filing-machine

Collection of pin-rails

Pin-rails loosely attached at their designated location

 

To be continued …

[druxey]

Lovely micro-milling and drilling work. I'm smiling! Great progress in the month I've been away, wefalck.

[wefalck]

Thank you very much for the kind words and the many 'likes' 👍🏻

 

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Pin-rails 2

 

As can be seen on drawings and old photographs, the pin-rails often rested on consoles attached to the bulwark stanchions for added strength. As about a dozen were needed, they were ‘mass-produced’ from a shaped styrene profile.

Milling the profile for the consoles to support the pin-rails

The shaped profile for the consoles

 

A 1.5 mm x 1 mm rod was stuck to a small ‘wax-chuck’ on the micro-milling machine with doubled-sided mounting tape. The rod was then oriented exactly parallel to the axis of the cross-slide and a hollow milled with a 1.5 mm ball-end burr.

Slicing off consoles with the micro-guillotine

 

The edges were rounded with a fine file. This profiled rod was then transferred to the newly built micro-guillotine and slices of 0.7 mm thickness cut off. These miniature consoles then were stuck to the underside of the pin-rails. Once painted, they will be attached as units to the bulwarks.

Collection of consoles

Consoles cemented to a pin-rail

 

Micro-Guillotine

 

The micro-guillotine was constructed around a part-machined cast-iron blank for a staking tool I found on ebay. Originally, I intended to fabricate all parts from steel, but I could not obtain a suitable blank for the rotating table and neither had the right steel bars in stock. So, for the time being at least, the parts were fabricated from 3 mm ABS sheet that I happened to have. 

 

The cutting blade is a shortened chisel-shaped scalpel-blade. It is set into an exactly fitting slot in the 6 mm steel runner and secured with a steel ring. The knob on the runner is an old bakelite instrument knob. The 6 mm wide blade restricts the cutting capacity to 3 mm for 90° cuts and correspondingly less for cuts at an angle. This is a conscient restriction, as this tool is really meant to only cut parts up to 2 mm by 2 mm cross-section. 

 

To cut at an angle, the plate is turned, rather than the cutter as in other designs. The narrow gap between the guides ensures that also very small parts can be cut. Their length can be set by the adjustable brass stop.

 

To be continued …

[BANYAN]

Every time you post these wonderful machines you have created you give me a severe case of 'tool envy' Eberhard.  Nice work on both.

 

cheers

 

Pat

[Jim Lad]

Just catching up, Eberhard. you do magical things with precision machinery.

 

John

[wefalck]

Pat, I used to suffer from 'tool envy' for many years, until I entered professional life and was able to acquire machine tools. And as we know, machines/tools allow one to make more machines/tools. It kind of developed into a secondary/subsidiary hobby then, together with the supporting process and market knowledge. I love in particular the look and feel of pre-1950s tools and machines, before everything became plasticky and boxy.

[BANYAN]

10 hours ago, wefalck said:

I love in particular the look and feel of pre-1950s tools and machines, before everything became plasticky and boxy.

Couldn't agree more mate. A well made 'solid' machine instead some of these mostly plastic offerings like 'choppers', some bench saws and the like just don't feel right.

 

cheers

 

Pat

[wefalck]

Pin-rails post-script

 

When trying to fit the pin-rail with the consoles attached, I realised that I had overlooked a point: the tumble-home of the bulwark. This means that the angle between the pin-rails and the bulwark-stanchions is not 90°, but is a slightly obtuse angle of about 100°.

In consequence, I had to remake the consoles with this angle. As the process is essentially the same as described in the previous post, I am only showing a picture of the final result.

Pin-rail on consoles affixed temporarily

 

 

Another small tool-making digression

 

Milling the above profile required that the stock is oriented perfectly parallel to the X-axis of the micro-milling machine. While orienting the little vice is quite easy with the help of squares, orienting the stock on the face-plate would normally require tramming it in with a lever-gauge. The problem is that the lever gauges are far too big for the little milling machine. So far, I have eye-balled it with a pointed cutter in the spindle and some light test-cut to verify. This has been somewhat time-consuming and unsatisfactory.

Thinking about the problem, I remembered the so-called ‘wiggler’ (https://www.instructables.com/Wiggler-Center-Finder-for-the-Lathe/) and designed a tool based on the same principle. It is basically a stick that is pivoted at some point along its length, so that it can move freely at an angle. There is longer and a shorter end. The latter is brought into touch with the workpiece and any movement is amplified by the longer end.

I miniaturised this to a total length of 33 mm so that it fits easily between the milling spindle and the cross-slide. It consists of a piece of 6 mm diameter aluminium rod, that is turned down at one end to 2.4 mm to fit into a collet of that size. The diameter was chosen, because it is the shank diameter of the common burrs that I often use as milling cutters. That saves changing the collet after tramming.

Mini-lever-gauge and its ‘mechanism’ (right)

 

The rod is bored out 3 mm along most of its length and a 4 mm recess of 1.5 mm depth is turned in. This recess takes up a disc that has been punched out of a section of some polyethylene tubing. The feeler lever is an ordinary clothes pin, the head of which has been turned concentric (the stamping process of the pin production does not lead to completely concentric heads). At the upper end of the bore, a section of the aluminium rod is milled down to half the diameter, allowing to observe the movement the pin in this window.

The polyethylene disc is secured in the recess with a drop of general-purpose glue and the pin pushed through it concentrically until the pointed end arrives at the milled-out section. The flat has a few lines engraved to be able to better judge the movement of the point. With this the little tool is complete

In use the pin-head is brought into contact with the workpiece and the slide moved a tad in until the point coincides with one of the lines. When running up and down the workpiece edge, one observes the movement of the point and adjusts the angle of the workpiece until the point remains steady.

Tramming the mini-vice with the aid of the lever-gauge

 

The tool is perhaps a bit crude and not as sensitive as a commercial lever gauge, but it serves the purpose.

 

To be continued …