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IronShips

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About IronShips

  • Birthday 07/26/1969

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    Zürich, Switzerland

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  1. Hi Valeriy, Not sure if BLAGOEV had any crew accomodation in the Fo‘c‘sle, although this was on many ships the case or even standard, as Roger said very correctly. Space in the Fo’c’sle on BLAGOEV appears to me as too small for the deck crew of a vessel of this size and on the photo of BLAGOEV you have posted no portholes in the fo‘c‘sle are visible, although both would not have stopped a shipowner to squeeze some crew in there… 😞 More importantly, crew accommodation in the Fo’c’sle are not indicated in the sideprofile of BLAGOEV, whilst all other accomodations are. Engineers accomodation were at the side of engine room casing, as indicated on the profile. Captains Cabins was traditionally located in the fwd Deckhouse on the starboard side. Best regards, Daniel
  2. @ Roger: According to my knowledge, on early ships the hot rivets were hammered from outside into the tappered rivet holes of the shell plating, countersunk rivet heads outside. Whilst still hot, the rivets were formed and finished off inside to form the mechanical lock. The rivet heads (outside) have then been further flattend by hammering. I believe the method you are describing came up with the invention of the air hammers. And you are correct, the picture I posted fits rather in this period. Either way a reason not to show hull plating rivet heads outside a shipmodel. 😌 Always happy to learn more! @ Valeriy: Thearle is indeed a fantastic reference. All his books! The book you are showing and the plates (harder to get) illustrate very well the different types of rivets used in different areas in ship construction in the past. Merry Christmas to all! Daniel
  3. Dear Phil, this confirms others and my opinion, I guess. The look of the rivet heads in the exterior of the shell plating as you are describing was fairly standard and reflects very much the original appearance of riveted hulls dating even back to the mid of the 19th century. The exterior doublers above the waterline are typical for some warships of a certain period and can be easily reproduced in model scale, if wanted, but as you say, hands off of flush rivet heads. I attach a close up photo (white) of the hull of the Danish yacht DANNEBROG, build in the 1930s and very nicely preserved to her original conditions. I don‘t believe such rivets would be visible in a scale of 1:48 or even smaller, but as mentioned before, very open to learn better. (Note: As mentioned in my previous post, talking about standard exterior hull plating rivet heads only.)
  4. Some more considerations on replicating rivets on a ship model hull: I am currently working at a model of a iron brig built 1865. I have decided to try to build the hull of the model from steel (photo attached). Tests are positive and I hope I will be able to publish a build log here one day too. 🙂 The regular hull rivets* of the original brig were 3/4 inch in diameter (Source: Lloyd‘s Iron Ship Report). At the exterior of the hull, the heads of the regular shell rivets were sunk. Let‘s assume the sunk heads were somewhat larger in diameter than the rivets as such. At a scale of 1:48, the sunk heads would have been therefore of a diameter of approx. 0.45 to 0.5mm. (Sorry for switching to metric). Furthermore and although being called „sunk“, the rivets were normally (not always) slightly protruding from the surface of the shell plating for manufacturing reasons. Having been involved in the restoration of classic riveted vessels (at full scale) my „guesstimate“ is that these rivet heads have not been protruding more than 0.5cm (generous assumption). As a result, we are talking about a detail of 0.5mm in diameter and 0.1mm high, prior to the application of any hull paint (min. two coats on the original ship). I am open to suggestions, but I believe such detail would not be really visible on a model hull at a scale 1:48. At 1:96 or 1:100 even less. It might be worth, though, to execute some tests at 1:48 or larger scales. I think we all came across some shipmodels with rather oversized rivets of far too large spacing and pitch. This might be appealing from a decorative point of view, but is in my opinion rather the contrary of a accurate scale reproduction. Also, old worn out iron ships cannot serve as an example for the quality and appearance of the original riveting. To see how fine early riveted iron ships were built, one might visit the website of the State Library of South Australia and search for the bow view of ships such as the CITY OF LAHORE or the PARSEE. I find it astonishing that no rivet heads are visible on the photographs, altough the black and white pictures are crisp clear, sharp and rich in detail. * Note: Rivets connecting the hull plates to the stem, keel, rudder stock were usually 1/3 larger in diameter than the regular hull plating rivets on such ships and also kept a bit more protruding. Furthermore, rivets installed on significantly larger vessels, often in way of sheerstrakes, frequently fitted in combination with double and tripple plating and riveted together with hydraulic means, are of different type and sizes and are a different subject.
  5. Hello all, Truly a wealth of experience and knowledge reflected by the many valuable comments posted here! Thank you all for contributing! At least for me it is a interesting read, and I hope for Valeriy too. Javelin has correctly explained in greater detail the wheel effect, and therefore the reason why I believe the starboard side could have been the preferred location for a single-side sea chest installation. I wouldn‘t rule out that ship designers have taken the preferred side going alongside into consideration when deciding on the location for a sea chest, as it is done for other equipment too. It is also correct that a berth is usually allocated by the harbour master, however, it is usually at the discretion of the Captain or the pilot in which direction the ship shall be moored. Cargo operation, wind, currents, navigational restrictions, the wheel effect, the ability to leave port quickly etc. are factors in this decission making process. With certainty, I can say that sea chests on commercial ships were not and are not to be fitted in the area of a cargo hold, a bunker or a tank. It is the design intend to keep the engine and boiler compartments compact. A sea chest location remote from the engine room would not have been practical and perhaps not even serviceable. In this regard, commercial ships cannot be compared with warships. As mentioned by Roger Pellett, it is surely correct that sea chests are kept close to the condenser(s) as surely one of (if not the) main consumer of seawater onboard the ship. However, a ships propeller is clearly designed for a forward direction, which is the more efficient direction of the propeller. Standard is a clock-wise, or right hand direction (looking at the propeller from the aft of the ship). If a propeller can be directly fitted to the engine shaft without gearbox is a matter of engine rpm’s, possible propeller size and a few other factors. However, a direct installation was the case with most steam engines as well as it is the case with large commercial ships fittes out by slow-speed two stroke diesel engines nowadays. It was therefore irrelevant if the design of a ship steam engine was a twin, a compound, a tripple or even quadrouble expansion engine. Also steam engines have a preferred forward direction. This is usually the direction in which the crossheads push against the slideguides when going forward. In the meantime, I have consulted the website of the Lloyds Register Foundation over the last couple of days, trying to find some drawings answering the matter currently under discussion. (Information on SONGA can be found there too.) All historical drawings of sea chests installations on single screw vessels I found on the website show starboard side installations. However, the drawing of UHENFELS Valeriy had published shows installation of the sea chest on port side. Some correspondence published on the website dating back to the 1920s is suggesting that not all commercial ship at that time were fitted with sea chests. There is a drawing of the vessel ALIOTH built 1937 in Germany on the website, showing a detailed sea chest installation, upper and lower sea chest fitted on starboard side of the vessel plus a a side profile. As both drawings show the frame numbers it can be easily determined where in relation to the main engine installation the sea chest were fitted in the engine room of this vessel. A seawater piping diagram of s similar sized commercial vessel of that period would probably answer many questions. Not sure if anyone can help here. Best wishes, Daniel
  6. Hello Valeriy, The following is purely speculative: Taking the sideprofile of BLAGOEV (ex. SONGA) profile as published into consideration, a logical location for a sea chest would have been between frame 69 and 72. The boiler seem to have been fired from forward. The manifolds were probably located at the forward end of the engine room compartment and in addition, some space was needed to service a sea chest, therefore a sea chest was unlikely located forward of frame 72, if fitted. Somewhere aft of frame 69 the engine foundation must have started and would have collided with a crossover normally (at least for the last couple of decades) fitted in combination with a sea chest. Hence between frame 69 and 72 as a proposed location. Again in the realm of speculation: Assuming the steam engine of BLAGOEV was turning right hand (clock-wise) going forward, the prefererred side to go alongside would have been portside. It would have therefore been logical to install a sea chest on the starboard side of the vessel, usually facing the waterside when laying in port. Model makers might follow different philosophies when it comes to speculative details. I understand you want to fit a sea chest to make the ship look more real and therefore not to ignore such a important detail. Good luck with your project! I love these old steamers 😀 Daniel (As mentioned previously, I feel uncertain when sea chests have been introduced to ship construction. Any hint from any member on this forum would be much appreciated.)
  7. Dear Valeriy, My interpretation of the drawing is as follows: The hull plates are overlapping for riveting purposes (lap joints, no butt joints). On the port side of the vessel and as strengthening, the underlaying plate is extending more forward to serve as a doubler for the installation of the sea chest. As a result, the extra extension of the overlap is not visible from outside. It is also correct that on large, modern ships usually two sea chests are installed. One is fitted to the bottom of the ship (in German „Tiefsauger“) whilst the second one is located above the turn of the bilge at the side of the ship (in German „Hochsauger“). The deeper sea chest is used in open waters, so that the flow of the cooling water suction is not effected by the state of the sea. When the ship is approaching port and is entering shallow waters, the engineers switch over from the lower to the upper sea chest to minimize the vessel picking up sediments through the lower sea chest. Sea chests are usually used for sea cooling water inlets. Inside the chest, a filter system is installed. You are correct that a sea chest is usually protected by a steel grill fitted to the hull. (I would assume that the bars of such a grill were made from flat iron bars, mounted vertically and perhaps with a spacing not exceeding 4“ or approx 10 cm.) Sea Chest are centralized locations to collect cooling water from the sea, serving various consumers of the vessel. Condensers are large consumers amongst them, as mentioned above. Sea chests are usually fitted in the vicinity of the „pump station“ in the engine room, where the main seawater cooling and fire fighting pumps are installed. Cooling water outlets are usually not combined in sea chests and are located in various places in the ship, often passing the hull shell above the waterline to minimize backpressure. I was also wondering when sea chests have been introduced. Prior to the introduction of sea chests, cooling water was picked through various inlets in the shell, which was not ideal from a maintenance and a safety point of view. I have been dealing with two medium size vessels built approx. 1930 which were not fitted-out with sea chests, which I found rather strange as sea chests are a effective whilst relatively simple concept. Regards, Daniel
  8. Roger, I understand how you are feeling. For me like many others it is the same, just the other way around! ☺️ I have grown up with the metric system. However, during my restoration projects (some of them in scale 1:1), I have found out that it helps to stay “imperial” if the original ship was build “imperial”. We never have all dimensions on our plans and shipbuilders have always been trying to use simple, straight forward measurements and dimensions. Reverse engineering some details of a ship, no matter of the scale, it helps to come closer to the original.
  9. reading the other comments, I believe it is indeed better to leave it as it is 🙂
  10. Hi Jonathan, Let us know what you did and how it worked. D.
  11. Dear Jonathan, I never done this, and other members of the forum might have better ideas. It wouldn‘t be my preferred method how to treat such delicate turned parts, but how about putting a tube over each tail, always same distance with every cannon and then bending the tail using the tube as a lever? Warming up the end of the cannon with a torch before bending might assist in the process. You might have to be careful that the edge of the tube does not leave a mark on your cannons. Best regards, Daniel
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