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wefalck

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Everything posted by wefalck

  1. I believe the scuttled ships in Scapa Flow are not only protected was a war memorial, but expressedly as a valuable resource for low-background radiation steel.
  2. Yep, this was a many decade-long experiment to map ocean currents. The Deutsche Seewarte published sailing handbooks for the various oceans with the view to speed up voyages (not only of sailing ships) and to avoid recurrent adverse weather effects. Such experiments are still carried out, albeit with the aid of modern technology, such as radio-tracked buoys or buoys equipped with GPS, that at intervalls report their positions.
  3. There are 0.2 mm sheets of styrene I wonder, whether it would be possible to take a sheet of clear Perspex / Plexiglas and directly 3D-print the pattern of mutins on it, rather than on the usual base. I personally have no experience with this kind of material, but some people draw out over a heat-source waste styrene from kits into thin 'wires'. This might be easier to work with, than wire. It probably needs some practice to obtain wires of uniform thickness.
  4. The size of the window panes would depend on what material/process was available at the respective time and region. If I remember correctly (didn't cross-check on Wikipedia ...) float-glass was invented at the end of the 18th century in France (the glass-maker, St. Gobain, are still one of the biggest manufacturers in the Western world). So, French ships might have had larger panes, then could be traditionally made by blowing a cylinder, cutting it up lengthwise and then flattening it out. Thinking about the problem, I wonder, whether it would be feasible to cut the frame-pieces from styrene strips and assemble these on a drawing of the respective window, as David suggested. If you go for rectangular cross-sections of the strips, you don't need to bother with mitres. However, if you were giving them a profile with a scraper, you would need to mitre them - but this would be quite a challenge in 1:192 scale, I think. In a next step you can cut the individual panes from clear styrene-sheet, fit them carefully and then drop them into the grille with some liquid styrene-cement. A 'cheaper' variant of the above would be to assemble the above grille with water-soluble glue on a drawing and then to cement a clear styrene-sheet onto the back. The drawing then can be removed by soaking the assembly in water.
  5. Zu Mondfeld died some years ago and I think, the series is not continued.
  6. I don't know von Mondfeld's books, but I tended to shy away from them a his coverage is to broad and he surely was not an expert on all the periods. I understand, that there are also quite a few errors in them. The safest way is always to try to dig up primary sources from the period in question. Obviously, there are regional differences in practices, but as ships and people moved around in the Northern European region (Baltic, North Sea), so that practices diffused around it. So, one can look around Swedish, Danish, British and the scantily available German sources (Images, drawings, models, etc.)
  7. The geometry of the movement of the tiller is a bit complicated, as the rudder-shaft is inclined and it does not form a right angle with the rudder-shaft. The outer end of the tiller, of course, will move in an arc around the rudder-head as seen in plan-view. At the same time. looking from the front, the outer end of the tiller will move in arc downwards from the highest point, when it is in the middle. At the moment I don't have the possibility to make a sketch, but I would think that there will a block attached to each side of the bulwark approximately, where the tiller would touch it, when put 'hard over', that is a bit backward from the front edge of the after cabin. Two single blocks would be attached to the front end of the tiller. So the runner of the tackle would be fixed to the block at the bulwark, led to the block on the tiller, run back to the bulwark block, and then from there forward. The arrangements would be mirror image on port and starbord. There could also be a lead-block a bit forward of the rear-cabin edge so that the runner can clear the cabin roof without chafing. Please note that this is purely conjectural and one may need to have look at (contemporary) models, for instance, for examples. Below there are some images from models that were constructed around 1900 by professionals for the Altonaer Museum (Hamburg) on the basis of plans and paintings etc. from the 1820s to 1850s. This is obviously about 100 years later than your example, but the principles have not changed much. I don't have pictures of 18th century examples. Above a schooner model that more or less illustrates the example that I have tried to explain above. The image above shows an arrangement similar to what you have, where the tiller is quite low above the raised after deck ('roof') and does not protrude a lot beyond its edge. No tackle was provided, so I am not quite sure, how the tiller was worked, when the rudder was hard over. As a matter of fact, the area of these rudders is quite small and they were mainly used to initiate a turn, which was mainly affected by taking away sails either before or after the mast to make the ship turn into the wind or away from it. It also served to keep the ship on a steady course, correcting small deviations due to jeering.
  8. Not sure that the downloadable files and those on the CD-ROM have the same resolution. I copied the original book way back in 1978 I think, eventually go the real one and the CD-ROM. I wish someone would have measured up the surviving German boats just after WW2 in so much detail, as Nielsen did for the Danish ones. The book includes also a number of German boats, apart from the Zeesboot also a dug-out(!) used in the Kiel Fjord to transport fish to the market, rowed by the fishermen's wives. While there are quite a few drawings made during the early GDR days (by Wolfgang Rudolph) and in the 1990s/2000s in the same area by Helmut Olszak, there is virtually nothing for the area of Western German Baltic and North Sea coast. Will be following the progress on this project, as Nielsen's book has always been a source of inspiration for me.
  9. These packets or 'postjagten' were used on established routes around the Baltic to transport passengers and mail. At that time what is today known as the Vorpommern region of Germany was under Swedish administration (from the Westfalian Peace Treaty in 1648 to the Vienna Congress of 1815, when it came to Prussia). There were regular connections between Stockholm and other Swedish ports on one side and for instance Stralsund on the other side. These sloops were heavily canvassed for speed and owing to the square-sails presumably required a quite large crew. A much larger one than the comparable commercial 'jagten' had, that were usually sailed with only three or four hands, including the master. As to the tiller, I would assume that it was operated with the aid of tackles, rather than directly by hand. There are a number of drawings of similar 'postjagden' in the archive of the Danish naval yard in Copenhagen: https://www.sa.dk/ao-soegesider/da/other/index-creator/40/3353816/17149179. They may provide additional useful detail. Check out the drawings with these archive nos.: G-4059 to G-4064.
  10. To me these boats look quite 'British'. For instance, Yarrow and Thornycroft not only built boats for the RN, but seem to have a big export business. I believe by 1900, the Russian industry was quite quite capable to produce such items of equipment, but often under design licence from the UK, France and Germany. I think many, if not most, navies contracted out the building of boats to private boatyards, often specialised in such things. The specifications were standardised and products were inspected by naval officers before being accepted for delivery. Boats to some extent were 'consumables' and the navies kept stocks to be able to replace them quickly - see e.g. the still existing boat-sheds in Chatham.
  11. Hey guys, this is building log on the GERMANIA by Keith. Perhaps we should start a new thread on how to blow up things
  12. I would also look into some serious dust protection measures for the (ball?)bearings. Ball-bearing don't lake abrasive grit too much ...
  13. The worst of all was our chemistry teacher at school. He was a poor experimentator and things never worked out as they should have. One day, he wanted to demonstrate the exothermic reaction of 'thermite' (an iron oxide and aluminium metal powder mixture) and did this on the tarmac school-yard - he ended up being summond to the director of the school for burning a big hole into the yard ...
  14. My father was a chemist and I had subsequently more complex chemistry sets ... at that time it was also quite easy to get chemicals, there was a 'technical' drug-store right next to the main department store in my university town. The more dangerous thing were those experiments we did 'off the record', such as trying to make gun-cotton 🥴 ... my father had a text-book on explosives making and testing ... I also made black-powder, but it was not very good. Today I would become arested as a budding terrorist, if I would try to buy the ingredients.
  15. I gather then you were a couple of steps up in the flow-sheet from me. With the British Geological Survey (1987-1992) I worked on contract research for BNFL, NIREX and the EU on the various shallow and deep disposal programmes. Even though I had signed the 'official secrets act', as an 'alien' they would not let me onto the Sellafield site, where we had a research project going on. As I was mainly there to 'computer model' radionuclide migration in the environment, fieldwork was only a minor part and 'entertainment' for me. We had some good trips around the country side on tax payers expenses (but don't tell anyone ...).
  16. Sellafield or Dounray? When? In the late 1980s/early 1990s I worked on the UK RWM (NIREX) programme for BGS.
  17. As there are hundreds or even thousands of plastics around I tend to check their persistance against solvents, alkaline or acid solutions in Wikipedia. There is usually a section or table on this in the Wikipedia on the plastic in question. If not Google helps to find other resources. Acetone dissolves e.g. polystyrene and acetate/celluloid, which is why it is often a constituent in the respective cements. It is usually sold in either metal containers (for mechanical resistance) or in HDPE (high-density polyethylene) bottles. (HD)PE is chemically rather resistant, which is why most chemicals and many foodstuff are sold in it. I am afraid, Nylon is pretty resistant chemically. I think the only solution is to burn it off. And one piece of advice (from a sort of chemist): never mix two chemicals, neither liquids nor solids, unless you really know, what you are doing. There are stories of housewives nearly killing themselves with chlorine gas, because they mixed two toilet cleaning products ... it seems that this subgroup of the population is particularly nonchalant in using chemicals (gues how I know ...).
  18. Ah, Pat, I didn't realise that the Byrnes is one of those 'end-less' machines. That makes things indeed more complicated. However, as you obviously will need a lot of LH rope, it may be worthwile to reconfigure the machine.
  19. Why doesn't the Byrnes ropewalk work not so well for RH rope? I would have that that this is just a question of cranking into the opposite direction. However, I am not familiar with this ropewalk. One may need to unravel commercial thread, if the twist is the 'wrong' way around, but that is not too difficult usually.
  20. ... then you would wish, it wasn't - it would cling terribly to your tools and these are not so easy to demagnetise.
  21. The subject of the colour of copper-plating seems to popping up over and over again. In seawater, copper turns to a dull brownish colour. It is only out of the water that copper turns green - if there is sufficient sulfur dioxide in the air.
  22. Could it be that such gratings above the stove were clad on the under- and inside in sheet-metal of some sort to protect the wood from heat and the steam? You wouldn't see this from above and modellers would not (haved) reproduce(d) it.
  23. Yep, lofting cant-frames on paper or in a 2D-CAD is not so easy, particularly providing the addenda for fairing, when cutting them out of wood sheet.
  24. Watchmakers and jewellers indeed use aprons. Watchmakers generally use cloth, while those of jewellers are made from leather. The latter clip to the underside of their workbenches, so that they can recover precious metal filings. It also protects them when silver-soldering. I have been wearing aprons in the workshop for decades. However, I found that small pieces mostly either bounce off, or just drop besides ...
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