wefalck

How true, I know someone very guilty of looking for complicated solutions ... 😊 BTW, I was wondering how these rotating freeing-ports would work, when there is a strut in their way. They would not be able to turn very much.

Way back in the early 1980s I used to program in BASIC, including driving a plotter. However, I think, technology has moved on since and didn't quite keep up with it From what I read diagonally, it should be possible to drive the laser-cutter from vector graphics, but for the moment, I don't really want to get into technology development. Producing parts is the call of the day, in order to get the SMS WESPE project finished - I have been on it now for 13 years, believe it or not ... I have been too often side-tracked by making tools.

Thank you very much for the kind words ! ******************************************** There are some really delicate parts lined up now, such as the frames for the freeing ports along the bulwarks. My original thought was to have them photoetched from 0.1 mm brass. However, given the difficulties I had in creating good, dense etching masks, I thought of trying a different route and something that is less messy. Laser-cutting seemed to be an interesting proposition. So I got myself a new little toy at 100€ incl. shipping. Toy is perhaps an adequate description for these small compact machines that are now on the market. Their design-purpose probably is to mark merchandise with a burnt-in logo etc. For this reason they are mobile, so items of any size can be marked by just putting the little (15 cm x 15 cm x 15 cm) box on them. Their power is limited, 3W. A mechanical resolution of 0.05 mm is claimed, with a diameter of the laser-spot of 0.1 mm. The engraving area is 53 mm by 53 mm. The software driver works by converting the images into bit-maps and then it runs them down line by line. I should try to find another driver that uses vector graphics, which would speed up the cutting process presumably. KKMoon-Lasercutter with a 3W laserdiode The software allows to adjust various parameters, including the contrast of the image, the power output of the LED, and something called ‘cutting depth’, though it is not clear what the latter really does. The focus of the LED can be adjusted manually to allow for materials of different thickness, but it is difficult to judge, whether really the minimum of the spot-size has been achieved. Given the power of only 3W, there are limitation to what materials can be worked with. The cutting resp. engraving effect depends on how much energy is needed to burn or vaporise the material. Paper works well, but a 0.4 mm cardboard seems to be the limit. I did not have much success with white styrene, only some light surface marks resulted even at the highest settings. Hard paper (phenolic resin impregnated paper) would have been my favourite material, but apart from the strong smell (the fumes are also not terribly healthy) a 0.2 mm thick sheet was only cut half-way through. Semi-transparent tracing paper does not take up enough of the energy and remains untouched. A sufficient optical density is required in order to absorb the energy and burn/evaporate the material. Strangely enough, the laser left quite visible marks on the piece of roof-slate that I used as fire-proof protection under machine. Converting a drawing into a cut-out piece is not quite straightforward. I first had to work out a way to scale the bit-map and JPEG images that I created from my CAD-drawings. The solution was to draw a box around the graphics to be exported, measure this box and then to scale the exported drawing in Adobe Photoshop to a number of pixels the resulted in the box of being of the desired size when laser-cut. The resulting scaling factor was 1 mm = 20 pixel, which was indeed the claimed resolution of 0.05 mm. On an image everything that is black will be burned away and everything white will remain. However, simply converting the CAD-drawings into images resulted in too narrow/small parts due to the fact, that the each burnt point has a diameter of at least 0.1 mm. Therefore, it was necessary to adjust the sizes of the areas to be burned away so that the remaining parts have the desired dimensions. The effect depends on the burning parameters and on the material. So, unfortunately, each new material and new part will require a certain amount of trial and error. I tried my luck on another set of very delicate parts, namely the steering-wheels. They have an OD of just under 12 mm. Turning the complex shape of spokes of 6 mm length appeared to be daunting task, even if one could have perhaps made the handles and the spokes themselves in two parts. The laser-cut ones look quite good after a few trial runs, but I have to see, whether I can build up enough thickness from several layers. Cutting them from 0.4 mm thick cardboard was not fully successful. Laser-cut steering wheels of 12 mm outer diameter I just wanted to share the first experiences with this new workshop toy and trials will continue. To be continued soon(?) ...

Normally, (some) maritime knots are designed to allow exactly that, to tie them while the corresponding rope is under tension. So choosing the right knot is the key. In many cases no knots are used to attach ropes, but rather lashings. Running rigging is 'belayed', which involves a sort of temporary knot. So, tightening involves loosenings the lashings or the belayed ropes. I would recommend that you get hold of a modern book on tying knots for yachtsmen, which explaines the basics that would be valid for at least the past 200 to 300 years.

No problem from my IP address in France ...

When I see the acreage and the barn-sized shed and then read the word 'down-sizing', what should I say with a 2 m by 2 m workshop-corner in my study/office ... ? BTW, someone above suggested to put the flooring around cupboard to save flooring material. Not sure that is terribly wise, because you may want to have floor-insulation all the way through and perhaps the flexibility to move cupboard etc. around, if the original design turns out to be not so handy.

My knowledge of shipbuilding practice in the 17th Century is close to nil. However, looking at sketch B above, it appears to be that a simple triangular chock would be forced inwards on any bending movement of the futtocks. This would constitute an inherent contructional weakness. When the chocks have shoulder, the bending movement of the futtocks would compress the chocks on the shoulders. Similarly, that sort of scarph in sketch C would lock the two parts of the futtocks together, thus reducing somewhat the squeezing-out effect on the chock. Mechanically, the solution C seems to be even better than A, as the outsides of the futtocks are locked together.

I know, some people use this material, most notably 'Doris' and Ab Hoving, but one has to remember that soft plastics, such as vinyl, will become brittle with age due to the plasticisers gassing out.

There could be other practical reasons: stowed sails, when humid, will rot, or when trying to shake out frozen sails, they may break ...

I am still wondering what, objectively speaking, the purpose of the sealing is ? Unless it is an operational model, there is not really a need to toughen the surface.

They look good indeed - apart from the price: six hooks for USD5 plus shipping 😳 I wonder, how they achieve the rounded effect, etching and then sandblasting ?

Well, that's a difficult thing to say. I gather, I have always been drawn to intricate things, in museums to the small highly-detailed models. Of course, I admired the big (board-room) models with their metal-work etc., but knew that I would have never the space for such a project - I hate giving away models, so I need to find the space to keep them. My first ('semi-scratch') model was in a 1:60 scale and then I continued in the same scale with the following scratch-built project. Then I realised that this was an unusual scale - it would have been better to go for 1:72 or something like that. Large scales, of course, are much more impressive for the casual observers. At some stage, I decided to go for scales in which figurines from the railway-community would be available, here on the European continent these are 1:87 (HO-scale) and 1:160 (N-scale), HO-scale for small boats and N-scale for larger vessels. The kind of limiting criterion was, that the overall drawing should fit onto an A4-sized paper. The challenge at these scales is not so much the machining as such (large-scale models could have also very small and intricate parts), but the availability of suitable raw materials. There is a limit down to which you can get wires, sheet-metal or -plastic or paper, or threads for making ropes. Sometimes also it would be geometrically possible to machine the parts, but the material just becomes to flimsy at small dimensions. Of course, it would be nice to also have larger machines - particularly for making attachments for the smaller machines However, my 'carreer' involved moving every few years, so I decided to keep my workshop mobile in the sense that the machines can be easily dismantled and crated or packed. The smaller watchmakers lathes come in fitted boxes anyway and for the milling machines I made solid crates. The appartment we will be retiring to in a few years time hopefully will have dedicated (small) workshop cum display room, but somehow my wife still tries to convince me that I won't really need it, as we would be out in street-cafés anyway, as the locals do in southern Europe ...

Future and similar 'self-shining' floor products are essentially dispersions of acrylic resins. So they are safe to use on acrylic paints. The curing of acrylic paints is a mixed process of forming cross-links of the dispersed acrylic resins and dewatering. The dewatering is a relatively slow process based on diffusion. This is why acrylic paints dry up rather fast, but stay somewhat soft for a considerable amount of time. When you apply a relatively thick layer of varnish (e.g. 'Future') over a relatively thick layer of acrylic paint, the latter will be prevented from diffusing out the water. In other words, the varnish might cure faster than the paint, resulting in shrivelling and cracking of the paint underneath. The same can happen, when you apply layers of oil-paint too early onto acrylic paint. Spray-painting of several thin layers of acrylics with some time between coats, give the paint enough time to cure thoroughly.

I am geochemist with many years of experience at the lab-bench ... on my work-bench there are no potentially corrosive chemicals, only paints and organic solvents (denatured alcohol, acetone, white spirit). When pickling or like processes are to be done, then away from the work-bench and near somewhere, where the parts can be thoroughly rinsed. Never use any cleaning 'products' of unknown composition on a model itself. It will be very difficult to remove any residues and they may creep into joints etc., where they can create havoc over the years. On copper I only use fine steel-wool and acetone. Don't use 'kitchen recipes' for patination etc. They may give more or less the desired effect, but it is important to create a stable patina that does not continue to eat into your metal or react with other components of your model. There are handbooks on patination/browning/blackening for metal workers, sculptors and the likes. Follow their procedures and recommended materials.

In Germany we used the funnel-pens directly with the templates. The templates had sort of rails above and below, which lifted them a bit above the paper and also allowed them to be aligned precisely on the horizontal ruler of your drawing machine. There is an ISO/DIN norm for the lettering and this standard lettering was mandatory for technical drawings. I think this 'font' is still used in CAD programs. For free-hand lettering there were/are also a wide variety of pen shapes. One form had small plates at the end, so that you were able to write with a defined line-width, but unlike the Barch-Payzant lettering pens, they cannot be run along a straight-edge. In art-class in my first year of secondary school we learned a bit how to work with such pens and ink. The area around Nuremberg specialised in making drawing instruments and materials. The Black Forest area was another area of instrument makers and precision machine tool makers concentrated also there. Many, indeed, seem to have produced not only their own branded products, but unbranded ones for the US American market, where they were labelled by the importers. This ended particularly with the on-set of WW2. This is an interesting piece of trade and manufacturing history ... but we begin to veer away from the subject of painting stripes ...

However, I would be rather hesitant to use any such chemicals on plates that are already on the model. It is impossible to prevent the solutions from creeping between the plates and there they may create havoc with the cement ... otherwise yes, oxalic acid is a good complexant for divalent ions, such as Cu(II), and will bring bring any CuSO4 into solution. I gather you meant to use the descaler 'CLR' as an alternative to oxalic acid not alternating between the one and the other ?

I would always be very hesitant to mix two paint systems. You may be lucky, but it can also spell desaster, depending on what the products actually are made of. Why would you want to put varnish over a painted surface. I would carefully reflect on the reason. Perhaps, acrylic paint isn't the right paint for the job, if you think you need to further protect it. Perhaps you should use a different paint system - there are also many different acrylics-based paint systems. Depending on the type of model, I personally also like the different sheens of different paints for different parts. A real ship would not be all over glossy or matt or satin.

I knew most of the drawing instruments presented above and have several sets, one was given to me, when I started in secondary school and it is still in mint condition, the others I inherited. However, I never came across the Barch-Payzant lettering pens, they must be an US American speciality. In Germany we used for this what would be translated as 'funnel pens'. They are indeed tiny funnels that can be attached to a penholder in a way to keep the pipe of the funnel vertical on the paper. They were made in standard diameters to fit lettering templates. A thin wire ran through the pipe to keep it from clogging. They were essentially the forerunners of the technical drawing pens with an enclosed ink-reservoir or cartridges.

OK, it's sure choice, but I wouldn't want to have bright plating .... having said that, if your copper turns green, you have a serious corrossion problem somewhere. Green means copper sulfate or copper acetate, usually. You may have not done yourself (or rather the model) a good service by using vinegar (acetic acid) on the copper. If the green appeared before you applied the vinegar, you should investigate, where the sulfur/sulfate may be coming from before doing anything else. Or perhaps you cleaned the copper with vinegar before applying the plates and did not neutralise and rinse it properly ? Normally, copper in a household atmosphere just becomes a dull copper-brown. At the seaside or in heavily polluted industrial areas this may be different, but Colorado is neither, I believe.

Gary, chromatography 'columns' are always stainless steel. Albion Alloys in the UK sell brass tubes from 0.3 mm OD up with a wall thickness of 0.05 mm. In fact they sell tubes that are slide-fits into each other, so the next sizes up would be 0.4 mm OD with a wall thickness of 0.05 mm and so on. They are quite expensive though. Not sure what they are normally used for, as I don't think they are made just for modellers. Hypdodermic needles are also stainless steel tubes essentially. The thinnest ones are those used for insulin syringes. Not sure about the size, but they could be below 0.3 mm OD. The raw material for the syringe manufacturers presumably are coils of such drawn tubes, but I don't know, whether one can come by this material as normal mortal.

Thank you to you both for your kind words. Unfortunately, the path is not so straight. Which is, in addition to frequent interruptions due to business travels, a reason for the long intervals between postings ...

I had the same thought about grounding, but these tubes would be difficult to solder - they are used as chromatograpy ‚columns‘ and therefore must by of highly corrosion-resistant stainless steel. There are on the market also brass tubes of a similar diameter, I believe.

Knots are actually a bit of intuitive engineering, meaning that people over the millennia realised what knot with what material gave the best holding power, while still being able to be loosened (which is a key property in marine knots!) if and when required. Originally, these knots where developed for twisted/laid rope. There, the holding power derives from two properties: the locking of the strands of the rope and the friction between the different parts of the ropes. For this reason, some traditional knots do not hold very well with modern braided ropes. For the same reason, these knots may not hold very well with straight or only slightly twisted threads. The surgeons use catgut or similar, more modern materials, which is only slightly twisted and quite smooth. Hence the overhand knot does not hold very well and the surgeons added more twists to it. The modeller faces a similar problem, when simple threads instead of a properly laid model-rope is used. One day, you may move to making your own laid rope or buy some ready made and you will see that the mariner's knots will hold much better with this material.

Didn't follow this thread so far, as it is not really 'my' period. However, looks like an interesting approach with the shop laser-cut parts. Just got myself a little toy laser-cutter to play around with ...

Instinctively, I would have glued the brass sheet to the wood, say using some CA or even a glue stick, but taking them up together sounds like a good idea.