wefalck

We had this discussion some place else, I think, already ... anyway, it seems that the friction in the gun tackles also transform a considerable amount of the recoil energy into heat. The breech rope was sort of the ultimate stop, as also the movement of the gun depends on the movement of the ship after the gun is fired. In later times, when slide carriages with different types of recoil brakes were introduced, the breech rope lengths were reduced to a minimum. There is a balance to strike between the maximum allowable strain on the parts of the gun and the breech-rope on one hand and the space for the movement of the gun on the other hand. Also, the further the gun moves away from the bulwark, the more difficult it becomes to control and bring back into loading and firing position.

Anything below the waterline would be, depending on period and location, covered in tar, some white concoction or copper-sheathed. So none of the caulking, if there is any, would be visible at all. One should perhaps also distinguish between caulking, a particular multi-step process using on planking, and covering the end-grain of wood in tar before assembling scarphs and the likes. Caulking on hull-planking could be also visible, when certain strakes for esthetic reasons were scraped clean and then oiled with some light-coloured concoction, which was fashionable in some areas and at certain times.

And, apart from deck-planking, this is only relevant, when you want to display your artisanal skills, rather than showing a 'real life' representation of the prototype. On a real ship, virtually all of that structure would disappear under thick coats of tar and paint ...

The Glowforge ones seem to be relatively serious one with a 40W CO2 laser, requiring proper ventilation etc. They also seem to have a serious price tag, starting from US$ 2500 (not sure about price over here in Europe ...). Perhaps one day I will upgrade, but for the time being I am making do with a cheapo (100 €) 4W diode laser and a 80 mm x 80 mm working area. Limited capabilities and precision, but it helped me to produce some small parts with complicated shapes that would be difficult to make in a different way.

If you use a fast-drying solvent-based varnish or sanding sealer, it is easy to stick parts on with exactly the same varnish. Nearly no need to hold things in place while a glue is drying/curing. I am first (laser-)cutting parts and then soak them in varnish. Resoak them after sanding.

Not at all, no soldering. As I wrote above, the stiles are simply cemented on using the brand cement UHU Alleskleber. Seems to hold on well for several decades now on glass and some five years on the first case I built from Plexiglas. I must admit, that I took the design from McCaffery's book on Miniature Ship models. He uses silicone to cement together the glass panes, as well as to stick on the stiles. At one time I found that I ran out of silicone and because of the weekend resorted to UHU. It is much easier to clean up than silicone, which tends to creep around (which of course is the purpose). Also, although McCaffery is really preoccopied with the longevity and stability of materials, he kind of ignores the issue of acetic acid fumes that form, when silicone cures and penetrate into the case.

(Some) silk has indeed a bad reputation among museum conservators and there are many models with decayed silk flags. It is a question of how the silk was treated after the worm has been killed in hot water and the cocoon unravveled. Some dyes are also acid-producing and lead to the destruction of organic fibres. Man-made 'silk' would not necessarily suffer from these problems. However, as one effectively creates a compound material with the silk embedded in an acrylic paint film some of the problems should not occur or be delayed. The UV-exposure, for instance, would be greatly reduced.

I way curious, as I was not aware of this implement with the two blades working against each other and checked it out. The instructions (https://www.micromark.com/Instructions/81858 sword saw REV 12-16.pdf) are a bit more moderate and state that their transformer is 'recommended'. So I would suspect that any electronically regulated transformer with 12 V operating voltage and 2.5 A output minimum would do.

I am also belonging to the no-sewing party, as any sewing would be grossly over scale on anything, but pond-sailing models. However, if you insist on sewing (for whatever reason), there is a simple trick to make life easier: draw the outline of the sail onto the fabric and then glue the fabric down onto some tissue-paper (of the kind used in the old days to make carbon copies) outside the sail area, but close to it. Both, the paper and the fabric have to be on a flat surface for the purpose. This helps to prevent the fabric from stretching and being pulled out of shape, when running it through the sewing machine. The paper has to be below, of course, so it, rather than the fabric is grabbed by the transporters of the sewing machine.

Yes. I think several people did it here on the forum. Check out 'dafi's' HMS VICTORY project for instance. You will have to remove first any moulded-on plating to create a smooth surface. Another question is, what kind of style you want to present your model in. In real life, the copper below the water-line would have been a dull reddish brown colour after a few weeks in the water. Around the water-line, between the water and the air, you would see some green oxidation (copper sulfate) and some white salt-stains etc.

Yes, this is a 1:60 scale model: I had some trouble keeping the boltrope in place, due to the furling, but I think today I would overcome this - the model was completed around 1995.

Sorry, I always thought that silk-span is the American expression for the light-weight silk fabric used for model airplanes ... I was talking about the fabric, not the paper. I have used silk-paper too.

That's why I was looking towards fabric ...

Same problem as for rope, thickness is not easy to define and measure the thickness of fabric. That's why the gauge is usually given in weight (grams or ounces) per area (square metre or yard, depending on where you are). One can make a rough estimate for threads, knowing the density (g/cm^3) of the material and the number of metres per g (given e.g. by the dernier number). Similarly, one can make an estimation of fabric thickness based on the weight per area and the thread-count and a bit of math, assuming that the threads in the fabric are perfect 'rods'. I looked at the silk-screen on ebay a while ago, hoping to find something thinner but more densly woven than my 14 g/m^2 silk-span and more tear-resistant than my silk-paper. I did study some art history at university for the fun of it and also collected a few books on art materials and techniques (before the age of Internet), so I am quite familiar with the variety of them. Useful knowledge for modelling.

I have not used or touched this, as I still have a life-time supply of silk-span that I bought in about 1978, but silk-screen for screen-printing might be another source of very fine silk.

Over the past 30 years or so I wrote/co-authored/edited probably a couple of dozen of books of various sizes for work. I also served on the editorial board of an UN organisation. And I am proof-reading/correcting four times a year the journal of the German equivalent of the NRG of which I am the legally responsible editor (not the technical one) ... Producing a decent book is hard work, though greatly facilitated by modern Desk-Top Publishing (DTP) systems. Getting all the formal stuff right, such as bibliographic references, credentials, permissions, etc. is indeed time consuming and tedious. I can fully understand that someone wants to spend his/her time with more sexy things ...

Actually, the silkspan sails are quite tough. I have used the technique since the late 1970s (in 1980 an article I wrote was published in a German shipmodelling magazine: http://www.maritima-et-mechanika.org/maritime/tips/FALCK-SM-5-80.pdf, see Figure 8 - 10 on the second page). As new materials became available, I switched from casein paints to acrylics. Depending on how much I wanted to have the structure of the silkspan visible, I choose the dilution of the paint. For the grommets I used paint thickened in addition with acrylic gel to give it more 'body'. For metal grommets I just made dots with a soft pencil to simulate the zinc-plated steel. This booklet of David Antscherl, were was it published or is it available as an electronic document ?

Thank you very much indeed for your kind comments ! These boats were not very stable gun-platforms and presumably very wet in any kind of weather up from dead-calm. Both, the North Sea and the Baltic tend to have short, choppy seas. ************************************ Display case – completion The display case was given a wooden plinth or frame from four strips of wood with 10 mm x 20 mm cross section. They were carefully cut to length with a mitre-saw and glued together ‘in situ’ to obtain a close fit. The wood was sanded, slightly watered, sanded again and then stained in a light mahagony colour. I decided to follow a simplified French polishing procedure. The wood was given a coat of sanding sealer and lightly sanded, so as not to sand through the staining. Shellac was applied twice with a soft cotton ball and the surface lightly rubbed in between with 0000 grade steel-wool. A short while ago the mail-ordered brass profiles arrived. I used a 2 mm x 4 mm rectangular cross-section for the bottom frame and 4 mm x 4 mm x 0.5 mm L-profiles for the corners. The bottom frame was first cut to size and the 45° mitres ground on my micro-grinding machine. These allows to achieve a perfect fit at the corners. The four stiles were polished bright with steel-wool and degreased with acetone before glueing them into place using ordinary craft glue of the UHU-brand (it’s solvent-based general glue). The next to go on are the four upper corners. The L-profile are sawn to length, the corners cut away with a side cutter and the precise mitre ground on. During the fitting and re-fitting the stiles are held in place with short lengths of low-tack tape. After glueing these into place, the four vertical corners can be tackled. First the two mitres are fitted into the existing corners, but each stile is cut a tad too long to have material for fitting. It is easier to grind them to length on the square lower end, then on the mitred one. The finished display case The Plexiglas and the wooden frame had been pre-drilled on the two narrow sides for a couple of brass screws that will eventually hold the case to the MDF-bottom. The seascape will be tackled just before painting the hull, so as not to damage the paintwork while sculpting the sea around the hull. To be continued ...

Reminds of the old joke: what is better than presence of mind in the case of an accident ... absence of the body. Sometimes guns can be more dangerous to the crew than to the enemy. Nice project btw ...

Too much work going on the last couple of weeks or so and not much time to look at the progress of colleagues ... the tracks have come out well, though I was wondering, like the other Keith, whether they really have been (wrought) iron and not bronze. We had a discussion on this forum a short while back about exactly that subject. I agree, that the photographs are not very conclusive. Personally, I would probably go over them with a soft pencil to give a kind of metallic look, but this depends on the intended style of the model.

The line-width in a (real) CAD system is zero. It is different, however, when we are talking about pixel-based drawing programs, where indeed a line (particularly if it does not run parallel with the axes of the system) can be several pixels wide. It would be bad practice to draw something on a CAD system, print it out and then take measurements from the print-out. Even in the old analogue days I would draw an item in 10:1 or 20:1 scale to reduce the effect of drawing inaccuracies and the problem of line-width. In the CAD-age the drawing itself is only something to orient yourself, the measurements are taken from the information stored within the system. Adding measurement bars in my CAD (EazyDraw) is a little bit awkward and makes the drawing rather 'busy', so I tend to make a print-out and note the relevant distances by hand. This then is the drawing from which I work on the lathe, the mill, or by hand. Lehmann is right in saying that proportions are what matters. That's why one should work 'outside-in' from the overall dimension, as I noted earlier. For many details there are handbooks (now also on the Internet) that give you typical dimensions. The human being hasn't changed that much over the past few thousand years or so, hence the 'handy' diameter of handles, rails etc. hasn't really changed, because hand-sizes haven't really changed. In fact ergonomics as such haven't really changed (though behaviour and use of people may have changed), so that modern dimensioning more or less gives you an indication. In most cases, for our kind of models the 'look' is what counts. If you are into working steam-engines and the likes, of course, exact dimensions to specifications are most important, otherwise the engine may not work. So, in our case we probably don't need measurements to 1/100 of milimetre ensuring the right kind of fit. Therefore, digital calipers are usually an overkill (though you can buy them from 15€ upward nowadays). I find them also too bulky most of the time and it is another item to maintain, i.e. making sure it has a working battery in it. My preferred caliper is a small vernier of only 15 cm length that can be easily used to control the work on the lathe or mill, but also on the bench. It has a 1/20 mm vernier, which is probably better then the working tolerances of most of us. You can estimate 1/60 mm easily, as thirds between two engraved lines can be guestimated. This, however, is better than the mechanical precision of the measurement, because of varying pressure you may apply on the part.

I noted something interesting on above picture: first I thought they didn't fit the floors/frames very well - but then I realised they left a gap between the floors/frames and the upper edge of the strakes so that no water collects in these corners and causes rotting ... Nice progresss !

Nice work on the sails !

Excellent ! I like the scenic setting ! I gather the boats sits on the ground between tides ? Or how is it otherwise hauled out ?

I have a natural science background and grew up in a natural science-househould. So, the natural thing for me was to make measured drawings, cut pieces according to the dimensions on the drawings and then assemble ... but often this did not work, perhaps due to poor manufacturing tolerances. I learned from watching craftsmen, who tend to cut pieces somewhat oversize and then fit them. Not the most efficient way in a production process, but very effective in an artisanal context - and shipmodel building is an artisanal process.