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Many people probably don’t realise how much work has to go into even such unassuming parts in order to get them right. Well done again ! Lockdown or not, I would have spent a good deal of Saturday in the workshop anyway. But as parts get smaller, there is only a limited amount of time you can strain your eyes ...

That's engineering ! Could you you show the machine in a tilted configuration ?

I like that 'divide et impera'-method for the chain sprocket. When I was doing it for my current project, I messed around with a tiny spherical burr. Sometimes one just needs to think of a strategy at the right moment ... Sherline doesn't do a compound vice. They only do a tilting table, on which their vice can be mounted. As I don't have enough space under the head of my mill for a commercial compound vice, I made a simple tilting fixture for a 25 mm toolmaker's vice from some 25 mm x 25 mm aluminium bar. The crucial dimensions were milled in situ: The angle is set using angle-templates between the surface of the vice and the spindle nose. I have a set in 5° steps. For other angles, one will need to mess around with a protractor.

So, how did you make the cowls ? Galvanoplastic ?

If I may chip in - I think there are three main limiting factors to working with small parts: Patience - this is up to you; I believe that in many cases when people claim that they cannot do this or that, what they really say is that they do not have the patience to do it (ok, eyesight and manual dexterity also play a role) Materials availability - sheet metal/foil is commercially available down to about 0.02 mm thickness, wires down to 0.01 mm, fibres for ropes down to about the same thickness; this puts physical limitis on the size of parts. Workability - the mechanical strength of a part decreases not linearly, but at the same rate as the volume; you cannot turn a copper wire of 0.1 mm diameter in the lathe; the precision of your tools also puts limits on the size of parts (remember that industry produces twist drills down to 0.1 mm diameter ... but their machines may be a thousand times more expensive than ours); 'touchless' machining techniques, such as etching, laser-cutting, galvano-plastic, or EDM offer(ed) there new possibilities. Working at a larger scale for me doesn't make it necessarily easier, as it means that you just can pack more details into the model - the absolute size of the parts to be worked on stays the same. Again, the level of detail is limited by the materials that are available and how it can be worked. For instance, at 1:350 I probably wouldn't represent door hinges, up to 1:96 scale I would represent it by length of wires, up to 1:48 I may shape the wire on the lathe and above, I may reproduce it in full. Or, at 1:350 I would not represent the rivets on rivetted parts, up to 1:96 I would represent them by surface etching and above, I may to go for individual rivets. We had the scale discussion somewhere else a while ago: I think the problem is that a typical (ship)model is viewed from different distances, unlike the situation, where a diorama (in the real meaning of the term) forces the viewer to preset viewing distance and angle (as for a theater stage). This means, that when you put your nose close to it, you expect to see all the little details, that you wouldn't be able to see say from a couple of metres away. So, for me the question is not the scale of the model, but rather what is the smallest part I have the physical ability and patience to reproduce ...

What can I say ... ?

France is entering an almost complete curfew tomorrow. We've done our shopping, but normal working life from home continues for me, with modelling in the evening. Good luck down under !

Good to hear ! Actually, I would be very much interested to see more about your locomotive pursuits !

There are two issues: not to spread the lead carbonate dust and to stop further corrosion. Just mop up the dust wet, not dry. Covering the lead parts in an impervious layer of paint may help, but there is no guarantee. A dry atmosphere helps. Avoid all acids.

I think we all would love to see photos of the processes, the stages of fabrication, and not only the brilliant products ...

There is at least one quite good book on her foe, which might give some transferrable details: BOWCOCK, A. (2002): CSS Alabama. Anatomy of a Confederate Raider.- 191 p., Rochester, Kent (Chatham Publishing). Rigging practices may have differed somewhat between the RN and USN, but the various books on HMS WARRIOR might also provide insights into warship fitting out and rigging details of the 1860s. Plus of course the huge amount of research Pat has done ...

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This looks like the dreaded lead-corrosion, which is why museums ban its use in new models. Be cautious when mopping it up, not to inhale the dust. It would also be better not to use the affected parts. If you have the possibility, make a mold and copy them in resin.

As a matter of fact, there may be various types of alloys behind what people use as 'white metal'. Today Cd-free versions are common. The composition determines the melting point and the viscosity of the molten alloy, hence the capability or otherwise to fill fine parts of the mold. Unless you are going to work with it on an industrial scale, I would not be too concerned. Depends also what you mean by 'working with it'. Just handling ist not a problem and presumably you would wash your hands anyway, when you get out of your workshop. If you grind or file it to any large extent, perhaps a dust mask might be a good idea, but really only, when you generate a lot of fine dust that could be inhaled.

I would assume this is white metal. I have thoroughly decreased it with acetone and then spray-painted it with acrylics without a problem. Railway modelers tend to use an etching primer, but they handle their models. If you just install the part and don't touch it afterwards, you probably get away without priming.

I actually do have quite a bit of experience in doing the drawings for etching and have done some reasonably successful etching at home. The drawings as such are not the problem. My main obstacle was always to produce masks in which the black was sufficiently dense and uniform. The wet process part can be mastered, but is a nuisance (though I am actually a sort of chemist by training). I try to begin with that side of the drawing that has most details on it. For instance, the 'outside' of parts with rivets and such surface detail. I complete all the drawings that are going onto one fret. I arrange the drawings and then draw the fret together with register marks (a white dot with a cross-hair) in each corner. All this is 'grouped', as my CAD software calls it. The group then is mirrored. After ungrouping I can edit out all the detail, or add more detail, for the opposite side of the parts. By proceeding in this way, I ensure a (theoretically) perfect register of the drawings. The problem could be in practice, that the cutting software does not align two drawings perfectly to the zero point. Or the somewhat flimsy construction of the cutter does not ensure that the carriage with the laser returns to the same origin within a 0.05 mm. With the small parts I am producing, I need such close tolerances. I have no immediate intentions to try this out, as my needs are more or less satisfied with the pieces cut from paper. The problem with building from original drawings is that you have to develop all the model drawings and in order to keep track of things, this is done in an iterative fashion, iterating between drawing and building. Hence, I have been trying to turn etching into an ad-hoc process, as you would use say a lathe or mill. Otherwise, etching becomes very expensive, as you might not get it right in the first try.

The problem is that the cutting software does not allow to superimpose images, it does not have 'layers', as CAD software would have. Therefore, I am afraid it would be 'eyeball MK1'-registration ... If you do surface etching, it is not just mirroring the drawing. You will have to produce two different drawings that have to register perfectly. A very laborious procedure with a lot of scope for error. I usually make one drawing, mirror it and then change it.

Thanks for the kind words and the 'likes' ! ******************************************* The hydraulic recoil-brake The 30.5 cm gun in pivot-carriage C/76 was one of the first guns in the Imperial German Navy that was fitted with a hydraulic recoil-brake, at a time, when compressors and brooks were still the standard. The recoil-brake consists of a long cylinder with screwed-on cylinder-covers at both ends. The covers are pierced for piston rods and are sealed with packed glands. The piston rods are fixed at the front and rear end of the carriage respectivly. The piston is designed as self-opening one-way valve. The cylinder is filled with glycerine through a valve on top. The front-end cylinder covers acts also as cross-head and the upper carriage is linked up through two short forked connecting rods. The cross-head runs on a kind of slide to support the weight of the brake. The two piston-rods are only connected by the short piston, which also acts as valve, and that would not be able to support the weight. Working drawing for the parts of the hydraulic brake When the gun is fired, the upper carriage slides back and the piston is pushed through the glycerine, converting the kinetic energy of the recoil into heat. The valve in the piston prevents the upper carriage from sliding back into firing position. In order to bring the gun forward, the rear end of the carriage is raised by turning the excentric bearings of the rear wheels and opening the valve in the piston. To facilitate this, the rear piston rod is hollow and a spring-loaded valve-rod extends beyond the piston-rod. The valve rod can be srcewed in and out by the aiming gunner using a long lever. In this way he can let the gun roll back into the firing position in a controlled way. Unfortunately, not much of the hydraulic brake will be visible on the finished model, so that it was reproduced in a somewhat simplified way. It consists of five parts. The individual parts of the hydraulic recoil-brake (the grid of the cutting mat is spaced 5 mm) The piston rods were fashioned from clothes pins of 0.6 mm and 0.7 mm diameter respectively. Clothes pins are very suitable for piston rods, as they have a nicely polished surface. The eye of front piston rod was milled/filed from the head of the clothes pin. The cylinder was turned in one piece together with the covers from a short length of 2.5 mm round steel. On the micro-mill a hole was cross-drilled for another short piece of steel that had the cross-head pins turned on. This piece was soft-soldered into the cylinder cover. The packed gland is compressed by a hexagonal nut, for which the hexagon was milled on in the dividing head in the same set-up. The forked connecting links were laser-cut from paper and consist of three pieces each. The bronze housing for the valve spring was turned from 1 mm brass rod. The valve lever will be added at a later point. Dry-fitting of the recoil-brake into the lower carriage. It’s kind of a pity that the recoil-break witll be barely visible once the upper carriage is in place. Two grills for the guns crew and a protective tunnel over the rear end will hide most of it. To be continued ...

Indee, I could make a jig to locate both, the cutter, as well as the sheet metal, but the problem I expect is with the alingment of the images on the screen. One has to load the left and the right sides consecutively. However, with a carefully designed procedure it should be possible.

I hope my wife doesn't see this ! She keeps telling me, that I should apply my tools to something more useful, such as jewellry-making 😱

I didn't get around to give this a try, but I have the idea of covering some brass with a thin layer of black paint and then burn it away for etching. This would do away with the step of having to create masks. It should work for single-sided etching, but getting the brass aligned properly for burning on both sides would be a bit of challenge.

Brilliant !

I gather specific rigging plans and details are difficult to find, as they were to a great extent ‚shop practice‘. However, there are various textbooks and seamenship manuals that cover mid-19th century practices also for steamships from which one could reconstruct the rigging.

I have just added to the original post a screenshot of the cutting software user interface

Actually, it is not a K40. The 40 stand for 40W and this is a completely different anyímal. Once I had it hooked up to my wife's old MS Windows XP mini-laptop and downloaded the driver, I was seriously working on it within minutes. The learning curve was not with the machine itself, but hitting the right cutting parameters for the material and drawing in question.