wefalck

Brass can be cut with zero-rake tools. That's probably, why your broken drill works when ground flat ( which is, I assume, what you did ?). As it doen't have a point, it will not wander. I also made tiny end-mills from such broken drills.

Excellent pictures !

Actually, we learned this at school ... additive and subtractive colour and light mixing. I remember having to paint various types of colour wheels using the school-box of water colours. BTW, ochre pigments are not usuall 'made', unlike lead-white, but are mined at certain locations, such as southern France, where the iron-oxhydroxide occurs in a relatively pure state, without an admixture of clays and other silicates such as quartz. The mined lumps are broken down and milled in large calanders (similar to the mediterranean olive presses of old) before being flotation-washed to remove impurities.

The accuracy required is not only that of the calculation, but also in the transfer to the work-piece ... how does this happen then ?

I noted that you further developed your holding gadget. I like the idea of integrating a pin-vice. Also, you got now nice ball- handles !

Hhhmm, just thinking about error addition/multiplication ... using proportional dividers to mark out n equal divisions for planks along e.g. the circumference of a frame requires that you apply the dividers n times, thus likely adding n times an error of similar magnitude, e.g. because the dividers slip a bit on the woodgrain, parallaxes, etc. If you were lucky, you would make as many positive as negative errors, so that you would end up at the desired end-point. You could do the same process from the opposite end again and then middle out the differences. Not sure one gains a lot of time. Today I think I would take a paper strip and place it around the frame, marking the desired end-points. I would then measure the distance with a vernier caliper and take this measure to my drawing programme on the computer, that has been calibrated agains the printer to give a dimensionally correct print-out. I would then draw a long rectangle and have it subdivided into the necessary equal parts digitally and print this out. The cut-out strip of paper is then taken back to the frame. Alternatively, if you was to use paper templates for the frames, the subdivisions for the frames can already drawn onto the templates and no additional measuring on the model itself would be required. There are various other strategies I suppose. This is not to say that I don't find these instruments attractive as instruments. If they weren't so expensive, I probably would have got one myself already ...

Just for curiosity's sake, Druxey, could you post a picture of it ?

These ceramic fibre files sound interesting (put rather pricey) and I have not been aware of them. They say that they don't break easily, but I would be so sure about this for say a 0.5 mm x 0.5 mm file. Have to look into this for my filing machine. Here are the relevant Vallorbe-catalogues on files etc. for downloading. They don't give prices, but show the full programme: http://www.vallorbe.com/umv/ch/fr-ch/file.cfm?contentid=5154 http://www.vallorbe.com/umv/ch/fr-ch/file.cfm?contentid=5182 http://www.vallorbe.com/umv/ch/fr-ch/file.cfm?contentid=5638 In addition to the japanese slot-files mentioned above, you may also want to have a look at joint- or screw-head slot-files as used by watchmakers. They are in the first catalogue above, but can be obtained from other manufacturers as well. I also found a lot of useful abrasive tools at the dental technicians' supply houses.

I can see the uses for it and it may be a nice tool to have for the quality of being a nice tool. However, with computers, pocket calculators, spreadsheet programs, scanners, and (laser) printers around, so far I did not have a real need for a pair. I would rather invest the 100€ into something else ...

Actually, if you look at a real ship, there are only subtle variations from plate to plate, if any. Exposure to seawater tends to level out any original variations in the state of oxidation (which due to the fairly uniform and industrialised production process, even in the 18th century, would have not been considerable). So I don't quite understand what the purpose of this rag-rug appearance is. One should also keep in mind that oxidation colours that result from contact with ambient air are different from the colour that develops under water and at the water-air interface. The presence of sulfates and organic substances in seawater are mainly responsible for this. Rather than using an open flame for achieving oxidation colours, I would use a hot-air soldering-gun, where you can pre-set the temperature of the air-stream and thus have much better control over the process.

Actually, I didn't quite understand Chuck's question. Thought it must be some joke I didn't get. Of course 'pink', which seems to have entered the English (and in equivalent ways other languages) in the 16th century when cultivated roses became popular, became the denomination for a pale red. How 'pinkish' the pale red becomes depends on what pigmente or dye is being diluted by white pigment. The 'cleaner' red the reflected spectrum of the original paint is, the more 'pinkish' the mixture will be. It also depends on the white pigment so some degree, as white and white are not quite the same. Titanium dioxide probably gives most comprehensive reflectance of the whole spectrum of the visible light and, hence. looks 'whitest'.

White washing, i.e. a solution of lime (calcium oxide, CaO, that forms when you burn chalk in a kiln ) in water that turns into CaCO3 by taking up CO2 from the air was extensively used in a domestic, industrial and also naval context, not only because it made rooms lighter, but also because of its slightly antiseptic properties due to the high pH value of the lime solution. The air perspective mentioned above would only apply, if you were to set the model into a scenic display or the like. Not sure one would use 'broken' or toned-down colours for display-style model, unless you want to simulate age. In fact, if you use the air perspective, strictly speaking, you fix also the viewing distance to some degree - the colour should become more vivid as you move closer to the model. However, one can argue a lot about this subject.

I gather, these cloth-covered hoses are quite flexible ? About 30 years ago I got a butane-oxygen torch, but a bit bigger than yours and found its hoses rather unwieldy. I was also rather reluctant to use it in the confined space of my workshop in an appartment - too much energy coming out of it, which is good for soldering, but not so good, if you accidentally drop it. An additional aspect is that I am mainly working seated, so that the lap is quite exposed to hot parts and equipment. I mainly use the little hand-held torch as shown above and if I have to silver-solder something a bit bigger, I use the electrical hot-air soldering gun to pre-heat it to 450°C. Somehow this feels more comfortable in my 4 m2 (40 sq ft) workshop space.

One cannot argue about tastes ... and colour, but I would describe the colour dafi was referring to rather as 'salmon' (ok, there are different ways of preparing salmon and hence different colours ...) than as 'pink'. Perhaps 'salmon' is more palatable than 'pink'.

Some belated thanks, gentlemen ! ******************************************** I could not refrain from some more toolmaking. I will probably add various small attachments for particular purposes, as I am using the machine. Here is a small clamping table for flat objects. It was milled from a piece of flat steel and the arbor for the 5 mm collet was hard-soldered in. The area underneath the slots is recessed so that I don’t need a wrench for holding the nuts while tightening the screws. It allows to securely clamp pieces of sheet metal etc. for engraving or other types of milling operations. It can also be clamped in the small holder I made for the micro-vise. You will see soon in the SMS WESPE thread, what sparked making this tool ...

Continuing with the barbette: the floor of the barhette is partially covered in planking, presumably to protect the armour-steel deck underneath from the damage that might occur, when the heavy shells are handled. The steel deck underneath and in front of the barbette armour-belt is slightly sloping to deflect incoming enemy-shells from the ammunition storage-rooms. Within the barbette this is filled with timber to make a level floor. Three different contemporary drawings showing the barbette The interpretation of the various items that can be seen in the contemporary drawings is not straightforward. However, one can see a hatch that gives access to the crew's quarters (where also the hand-cranks for turning the gun-carriage is located). Then there is a round hatch for hoisting up the charges from the powder-locker below and a square hatch for hoisting up the shells. From the drawings it appears that these hatches were covered in steel-gratings. There is a further hatch with a double-lid that, according to a hand-written notice on one drawing is a man-hole leading to the ante-room of the shell-locker. However, as it is not drawn in the cross-sections we do not know its height. There are also a couple of racks for shells and some other rack-like features, the purpose of which I do not know - perhaps for tools needed in handling the shells. Unfortunately, there are no photographic images that show the rear of the barbette. Stairs leads down from the bridge into the barbette. In addition two ladders allow quick access from the deck. The barbette with various items of furnishing The floor of the barbette, which apparently did not have any camber, was built up from two layers of Pertinax one representing the steel-plating and engraved accordingly, the second cut out and engraved to represent the wooden flooring. Milling and jig-drilling operations on the new micro-mill The construction of the various hatches gave the opportunity to test the just finished micro-milling machine. The man-hole cover was milled from a small block of Plexiglas. The machine was also used as a co-ordinate drilling machine for getting the holes in the rack in one line and evenly spaced. Collection of hatches for the barbette (the grilles still have to be straightened) To be continued ....

OK. I was wondering why for a model of such quality parts would have been made from plastics. This makes sense. CNC-milling or 3D-printing in wax opens up very interesting possibilities for lost wax casting or making masters ... if you have access to the technologies ...

The green parts also have been CNC-milled, I suppose ?

I have not been aware that the dialectric properties have something to do with the reflectance, will have to read up about this, but I gather this has also something to do that metals do not polarise the reflected light, while other surfaces do ... without going into the deeper physics of this, one important point is where on, or rather in, a surface the incoming light is reflected. Many real life 'surfaces' are actually three dimensional structures, albeit thin. Somewhere in this structure the light is reflected and may be bouncing around before leaving again. So, on a microscopic level, not the whole surface may be reflecting, while for metals it is essentially the whole (at least above the atomic level). Yes, I have been aware of the advances in media/paints to represent metal surfaces. The main point there, if you want ot represent a bare, polished surface, is to make the reflecting metal particles small and with the help fo the paint formulation to coerce them to lie down flat, so that they will form a continuous layer of more or less parallel oriented particles. For rough metal surfaces, such as the cleaned-up casting for the engine in the picture, this is obviously simpler. The varying angles of the metal particles in the paint mimic the sand-casting surface. I have achieved something similar by rubbing a soft pencil over a black or silver undercoat. And yes, it is quite amazing what seems to be possible today with products such as the Alclad metal paints, though I have not used them myself yet.

Dito, the crew were kept busy keeping things 'ship-shape and Bristol-fashion' ... of course they would have to be painted according to the materials that were used on the prototype. BTW, I am strong believer in the statement that nothing looks more like metal - than real metal ... where bare or 'patinated' metal was used, it may be a good idea to use the same metal, if possible (keeping in mind that iron and lead are being frowned upon by museum conservators).

N.B. NEPTUNIA No. 284 has an article by the Kriegsteins on "Le modèle d’un vaisseau de 64 canons, construit par Augustin Pic en 1754" in their collection (http://www.aamm.fr/boutique/index.php?main_page=product_info&cPath=67&products_id=522&language=en)

Having learned first about the material - my father was an electronics amateur, and then of the emperor, I always found his name rather strange ...

Another of the many projects I didn't follow (for a long time) - fantastic model ! And at 1:72 scale it come almost into my scale range and provides a challenge ...

Patina is/can be the sign of poor maintenance ... . I gather you refer to the kind of patina that develops naturally on the surface of certain metals. We know the brass cannon resting outside some museum or fortress and tend to think that is what they would have looked like in their active service life. Probably not. Patina refers to a surface layer that prevents further degradation of the metal due to oxidation or sulfurous/sulfuric acid (vulgo: acid rain). It consists of oxides and/or sulfates. It develops naturally on certain metals, such as copper, brass, or bronze, but not on others, such as iron and steel. Iron oxides and oxy-hydroxides (vulgo: rust) is porous and does not passivate the underlying iron/steel. Hence no natural patina develops on iron. One has to convert the 'rust' and bind it together, so that it forms an impermeable layer, preventing humidity from accessing fresh iron. This was done in the old days by rubbing iron barrels with vinegar. This provekes 'rust' but also produces some iron acetate compounds. These were bonded together and made water repellent by rubbing the dried barrel with line-see oil, thus creating a sort of in situ paint that adhered strongly to the iron. This is what is called 'browing' the iron. There are other, more recent chemical processes that are commonly referred to as 'blackening' and that is what they do. Again, the blackening needs to be made water-repellent by rubbing it with a non-drying oil (small arms) or a drying oil (cannon). Another method is to 'phosphatise' iron surface, which is essentially what modern automotive 'rust-converters' do. The technique is also used on hardware. The resulting iron-phosphates (Vivianite) have a very low solubility and form a hard continous surface cover. One can add colouring agents to the process. Coppper-containing metals, such as brass and bronze can be passivated by producing some sort of complex copper-sulfates on their surface. While the copper-sulfate as such has a blueish-green colour, by adding heavy metal, selenium and others to the process, one can vary the colour from a deep black, to brownish-green, to a deep brown. This is what sculptors and producers of metal-ware have done for millenia and when we think of 'patina', we typically think of this. This kind of patina is not very resistant against handling and needs to be renewed from time to time or otherwise the bare metal comes through. A well-maintained gun/cannon would have an even 'patina' over all the areas that are meant to be protected by it. Lack of maintenance for what good or bad reason makes itself visible by the bare metal coming through, or in the worst case by localised corrosion.

I gather Pertinax is one of those trade-names that has become a generic term, such as Hoover for the longer vacuum-cleaner ... In German the generic term is 'Hartpapier' i.e. hard-paper, which is paper impregnated with a phenolic resin and cured between steel-plates or -rollers to give a very smooth sheet of even thickness. The thicker varieties are best know as base material for circuit-boards before epoxi-resin took over the market. It is essentially paper-reinforced bakelite. I like it, because it is much stiffer than polystyrol/styrene and it does not contain softeners that can diffuse out. However, the material is very brittle and one has to careful, when working with it. Its hardness allows it to be sanded easily (as opposed to Polystyrol) and it can even be polished. The downside is also that it gives off phenolic fumes, when it becomes hot during working.