wefalck

Priming has the purpose of reducing corrosion (probably not relevant in our context) and to increase the adherence of paints. Copper and brass quickly develop a very thin oxidation layer that feels slightly 'greasy' and to which water-based paints do not adhere very well, particularly, when brushed on. In such cases a primer might be useful that makes the surface somewhat porous, improving the adherence of particularly acrylics. However, for small parts that are not handled priming in most cases is not really needed, particularly on models that are put under glass immediately after completion. In the case of working models, the situation may be different. Every layer of paint will obliterate detail and make the appearance of parts less 'sharp'.

We had this discussion at other places I think already. Acrylic paints are dispersions of acrylic acid molecules in water (possibly alcohol) with finely ground pigments suspended in them. The curing of these paints happens in two stages or perhaps parallel processes: the solvent, the water evaporates, and the molecules begin to intertwine, trapping the pigment in between. The first process happens within minutes (when spray-painting) or an hour or so (when brush-painting), while the latter process will continue for days or even a week or two. It is not possible to redissolve acrylic paints without breaking up the molecules, i.e. destroying the binder. You can, of course, grind up the dried paint, but all you get is a slurry, but not a paint. You would need to really finely grind it and then add new binder, i.e. acrylic acid solution - but this is not really worth the effort und almost certainly will not yield a satisfactory product. The same considerations apply to dried out oil-paints. Here the binder is lineseed oil and the curing process an oxidation induced by short-wave radiation, namely UV-light. Once oxidised, the process cannot be really reverted. Again, if you grind up the paint, you will end up with a slurry and would need to add more lineseed oil as fresh binder. Not sure that making your own paints from scratch is really an efficient process. Of course the painters of old did this, but then jumped onto the confectioned paints, as soon as these became available around the middle of the 19th century (facilitating the open-air painting of the School of Barbizon and somewhat later of the Expressionists). You are not likely to arrive at the same level of homogeneity and dispersion of commercial products. The resulting product may be ok for painting by brush of small areas, but probably nor for painting larger surfaces, let alone for spray-painting. This is one reason why the technique of painting, sanding, painting, sanding, and finally polishing was developed.

Was there a specific reason, why you used Novotex (bakelite with cotton fabric) for the drums ?

Varnish essentially is a 'paint' without pigment. The purpose of varnish is to protect (wood) surfaces. Modern acrylic paints are acrylic resin suspensions that have also very finely ground pigments suspended in them. They will form a uniform layer of physically (not chemically) cross-linked and intertwined strings of acrylic resin with the pigment imbedded. So, under normal circumstances no 'varnish' is required. However, if an item is to be handled frequently, an additional layer of varnish will be a sort of wear layer, protecting the actual paint. But this is likely to be relevant only for RC models and the likes. Most acrylic paints dry up with a satin sheen. If you want to have a high-gloss or real mat surface, one could apply respective acrylic varnishes to obtain the desired sheen. It is always wise to stay within one paint/varnish system. If you use acrylic paints, use acrylic varnish for the above mentioned reasons.

Funnels were double-walled from about the middle of the 19th century on. For two reasons: in order to keep the flue-gases hot to provide a better draught and to prevent the burning of adjacent materials. The internal flue was held concentric by spreaders.

Such rings would only be needed, if the covers actually sit completey inside the hatches. It they are designed to overlap the coamings, one can lift them off by just reaching under the edge. I seem to have seen this design at least in the second half of the 19th century. This would not prevent the tarpauline to be battened down smoothly.

Shellac is being used, e.g. by watchmakers to glue parts for turning operations onto flat discs, so-called wax-chucks. It is quite strong, as long as you don't jerk or bang it. It has the added advantage that you can take it off with a drop of alcohol, if you are not happy with the result.

Thanks, gentlemen, for your kind words. @Roger Pellet - from the early 1860s on, the experiments by various gun manufacturers to produce a gas-tight breech lock slowly bore fruit, notably those of Krupp in Germany. They constructed a lock that was based on a cylinder in a cross-bore that wedged the actual lock part in place. The key to success was a gasket made from hardboard. In the mid 1860s this principle was replaced by a system, whereby two wedges in a square cross-bore were pulled against each other, thus safely closing the chamber of the gun. The Danes, the Austrains, and then the French found that out to their detriment in the wars between 1864 and 1871 how effective these designs were. The French company Schneider began to develop breech locks in the mid 1860s, based on a segmented screw, which was the design kept for heavy guns and until the drop-block locks for cartridges were introduced for QF guns, based on a design by the German company Gruson. Krupp continued their developments and developed what is called a 'round wedge' lock (Rundkeilverschluß). Hereby a sligtly tapered lock-block is pulled into a correspondingly tapered cross-bore using a thin transport screw, while a short, coarse locking-screw pulls the block tight. The gas-tight seal is provide by a copper gasket that has to be replaced every few shots (while the hardboard gasket had to be replaced during loading for each shot). This remained the Krupp-design until WW1 for heavy guns. The 30.5 cm RK/l22 had this kind of lock and you can see the locking piece in the picture below: The screw that moves the block into place is the thin one on top, while the heavy locking screw is on its back.

A belated thank you ! *********************** Completing the upper carriage 1 With the lower carriage basically ready for painting, I turned my attention back to the upper carriage. The structural elements made from photo-etched parts had already been constructed many years ago. Dito some of the details had been fabricated more than ten years ago, or at least partially. The previous state of the upper carriage I had also turned and cut the gear wheels for the elevating mechanism, but they had not been finished. The back side, after parting off had not been shaped, which was done now and they were also chemically tinned after degreasing and pickling in citric acid. The gears as cut The elevating mechanism consist of a double reduction gears and is driven by a deeply dished handwheel with six spokes. These reduction gears are duplicated on each side of the carriage. The last wheel in the drive has a pinion on the inside of the carriage, which acts on a gear segment that is attached to the gun barrel. How the gear segment is guided is not clear from the available drawings and the model in Copenhagen. On the Russian Krupp-clones the arrangement is slightly different. The elevating gear train in GALSTER (1885) The elevating gears on the instruction model in Copenhagen The gear segment and its attachment to the barrel on a gun in the Suomenlinna fortress Krupp factory photograph of the same gun, but in coastal mount (from the collection of the Architekturmuseum TU Berlin) There is a friction-brake on the axle of the last large wheel of the gear train, which is worked with a cross handle. How this functions is not clear, but it presumably just pull the gear onto the frame via a short thread that is cut onto the end of the axle. On the starboard side of the gun there is a brass disc and an indicator lever that somehow shows the degree of elevation and presumably the range of the gun with different kinds of projectiles and charges. Again, how this indicator disc is coupled to the elevating gears is not clear, as I do not have any suitable photographs. In any case, the respective gear train will not be really visible on the model. The dished handwheel started life as parts photoetched from 0.2 mm brass. In order be able to bend each spoke into the dished shape, a former was turned from some round steel and set up on the watchmakers ‘staking tool’. The spokes were pre-bend by hand and then finally pulled to shape using a hollow punch. The parts then were chemically tinned and soldered together with the aid of some flux. The step-wise forming of the dished handwheel The remaining parts, such as the axles, are simple parts turned from steel rod for strength, as they are quite long compared to the diameter. (Almost) all the parts of the elevating gear laid out The elevanting gear provisionally assembled To be continued ...

OK, this is replica, but I think dark decks, at least for ships built in non-tropical areas, are quite unusual and often a sign of poor maintenance. Most decks are made from some sort of pine or perhaps teak. If not 'holy-stoned' regularly, the wood will attain a sort of greyish colour the older it gets.

Many people don't appreciate how much time and work goes into a job well-done. At least the community here does

In Germany and France at least there are nitrocellulose- or shellac-based sanding sealers that are 'filled' with pumice dust. The idea is simplify and speed up the traditional process of 'french polishing', whereby the wood was 'sanded' with a pumice stone and then shellac was applied, which consolidated the pumice dust in the wood pores, thereby evening out the surface. When you rub the wood down with steel-wool, it just takes away the excess sealer, but does not actually cut into the wood itself, as when you are using sandpaper. You immediately get a shiny and smooth surface without scratches. I have been using this process for at leat forty years now in furniture- and model-making. BTW, shellac is not really water-proof, as anyone knows, who put a wet glass onto a french-polished piece of furniture. Alcoholic beverages obviously are even worse. However, when you spray-paint with acrylics, the water (and the alcohol, if your paint also uses alcohol as thinner) evaporates so quickly, that no harm is done.

Shellac is a traditional glue, used by many trades ...

Try to find some nitrocellulose-based sanding sealer. Sand the wood, wet it, sand again (as previously mentioned by Jaager), let dry thoroughly and then apply the sanding sealer. Rather than using sandpaper, rub down the wood first with 000 steel wool and then with 0000. This gives you a nice surface without appreciably adding thickness, as you basically rub down to the wood and just leave the sealer in the open pore space. Such wood surface can be buffed to get a nice satin sheen, or indeed it can be spray-painted with any paint, preferably one that does not contain organic solvents, such as acrylics.

Shellac, lineseed oil, or acrylic varnish would be options. It depends on what degree of shine you anticipate. You may want to give the wood a treatment with wood filler, rub it down with steel wool and then put on the bands. The final treatment then could be any of the previousl mentioned or, indeed, nothing.

Planking thickness on the real ship will vary around the hull. Some of this is visible from the outside, namely the wales. You would need to check the thickness of the planking on the real ship from appropriate resources and then adapt it to the scale of your model.

I think the best thing would be to get some background information on her or the J Class in general. There are also some textbooks on yacht-building and rigging. I am quite sure that double-blocks would have also been used, say on boom-sheets.

Not sure you can see the pictures in this German forum, but a colleague there is just doing that, he uses down branches and trims them to shape: https://www.segelschiffsmodellbau.com/t7885f20-Slawenboot.html Or lamination from many thin layers (plane sheavings) over a former.

When I look at the linked picture, I don't think that any structure of the the aluminium? lining inside the hangar would be perceptible at a 1:350 scale. I would spray the internal structure in silver and then modulate the silver with a soft (e.g. B8) pencil to simulate the folds etc. in the lining.

I have not doubt that it works. The point was that there are cheaper materials and that there is a risk that the alloys change their properties due to contamination from the plating metals. So they may or may not be re-useable. But one would need to try.

There are many low-temperature alloys that could be used for this purpose, such as Wood's Metal, Rose's Metal etc. Melting points are somewhere between 50°C and 90°C, so that they could be liquidised by boiling in water. However, I am not sure, whether they wouldn't be contaminated by the plating metal ions and then change their melting point. They are also rather expensive compared to jeweller's wax for instance. I think I would rather go one of the above mentioned methods, than using one of the alloys.

One has to distinguish between 'plating' and 'galvanoplastic'. Technically the processes are similar, but the product and the set-up is different. Plating is, what is called a redox-reaction, whereby a metal is reduced from its soluble salt-form (broadly speaking) to the solid metal and deposited onto a metal or conducting surface. The redox-reaction can be purely chemical, then we talk about chemical plating, or it can be induced or supported by an electrical current, then we talk about electroplating. In the latter case most of the metal to be plated onto a conducting surface or another metal is dissolved from a solid electrode of that metal. The solution is thus continuosly replenished with that metal. Chemical plating can be done with a variety of metals. I just googled and there are many commercial kits available on both sides of the pond. The process can be done as a dipping or a brush-on process. It normally requires a metal surface and with the right chemistry, most metal can be substrate for chemical plating, though aluminium probably not, due to it quickly forming oxide layer. I regularly tin-plate etched or machined parts to give them a silvery look and to facilitate soldering. Often only the addition of flux is needed. Self-tinning solutions can be bought either ready made or as dry mixtures of the salts. They are also used by the fraternity that produces home-etched printed circuit-boards. Electroplating also can be done with many different metal. The surface to be plated can be a metal or any other conducting surface, e.g. a graphite lacquer. Not all metals can be plated on every other, so nickel-plating on steel requires a first plating in copper. Again kits are available on the market for doing this in a bath. For repair purposes also so-called tampon-plating kits are available. Here a felt 'tampon' is soaked in a solution containing the metal to be plated with, a cable is clipped to the part and the tampon pressed onto the surface to be plated. These kits are availble easily from jewellers supply shops for copper, gold, rhodium, silver and some other metals. Galvanoplastic is similar to electroplating, but a thicker layer (up to several miliimeters) of metal is deposited, with a corresponding need of electrode material. The model normally is non-conductive material, such as wax, plaster, wood or plastics that is made conductive by a graphite or silver lacquer. The process can be done as positive or negative. For the positive one a model of the object is made and then covered in the conductive lacquer. The final object is slightly larger than the model and some of the surface structures will have been evened out during the process of plating. Alternatively, a mould can be made from the object to be reproduced and the inside of the mould is covered with the conductive lacquer. The metal electrode and the salt solution is put inside the mould. The process reproduces every detail of the mould. It has been used since the 1840 to reproduce coins, statues and other metal objects. Today, CNC machining opens up new possibilities of model and mould making. Models can be milled or 3D-printed from jeweller's wax for either lost-wax casting in brass or for galvanoplastic. I German colleague now prints 3D-models in wax and has them cast. And @Valeriy V here on this forum CNC mills cores for ventilators for his cruiser VARYAG from wax and deposits copper on them to form the ventilators. The wax is removed by heating. One can do this also with acrylic glass or styrene and dissolve the plastic in acetone. The negative process with a mould has the advantage, that several copies can be drawn, while for the positive process you need a new core every time. As a kind of curiosum I should mention another process. I know an octogenarian in the UK, who sculpts the decoration for his model of the ROYAL OAK (1769) in Z-brush, has them 3D-printed in acrylic resin and then vacuum-plated with gold. This process, called 'sputtering' is a preparation step normally used in electron microscopy, when you want to examine fine surface details. In EM only a one atom layer of gold is required, for plating you need a bit more, of course. He is lucky that his sun is a researcher with access to the facilities. The process is not cheap because of the machine-time and the amount of gold needed. However, the results are just phenomenal - beats every carving with respect to detail and definition ... well, not exactly a low-cost option, which was, what this thread was about

At the very beginning I also thought that these structured acrylic glasses might be a good idea, but at least the ones I found at the time didn't quite look like waves, but rather than water droplets on a glass pane, so I gave up that idea. Unless the sea is dead-calm, it is probably better moulded or carved. There would be swell/waves of different heights and lengths. In most cases the sea would be translucent at best and you can see only through a top layer of a few centimeters, when you look sort from above. So one doesn't really need to have something that is completely translucent. Hence, the sea can be moulded say from plaster of Paris or carved from wood or hard foam and then covered with 'gesso' (essentially Plaster of Paris). The changing colours of the sea then are painted on. Finally one gives it a cover of glossy acrylic varnish. Splashes, wave crests etc. can be modelled using acrylic gel medium. As the sea is never really that glossy, except again in a dead calm, I stipple on with a bristle brush gel medium to simulate the wind effect on the water surface. I have described the process in more detail on my Web-site: https://www.maritima-et-mechanika.org/maritime/tips/makingwaves.html Here one example for a tropical lagoon using an acrylic sheet as the basis:

Interesting way to build the deckhouse around the furniture, inside-out 👍

Parrel beads is what you are talking about now. Here is my comment on that subject a couple of years ago: "Although I inherited a box full of antique very small seed-beads (at some stag,e embroidery using these glass beads was fashionable), I have been constantly hunting for them, as they never seem to come in the right colour ... The keywords to look for are seed-beads or rocaille (beads). Their size is given in either millimetres or fractions of an inch, i.e. a size 16/0 would be 1.58 mm in diameter. They seem to have been made traditionally by the Bohemian glass industry and in Venice. However, new stock seems to go down only to 18/0. If you need smaller ones, you need to hunt for antique stock. The smallest I have seen on Web-sites are 26/0 and my antique stock (unfortunately ivory coloured) falls into that size category. See also: https://en.wikipedia.org/wiki/Seed_bead" For beads of any size and description, just look around ebay, in the ladies' handycraft sections as well as in the nail 'art' section.