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wefalck

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Everything posted by wefalck

  1. The mounting of the chuck is not the problem, its the jaws and the mechanism that tightens them - they are not designed for sideway loads, but only for axial loads. Below (left) is a cross-section through a key-operated drill-chuck. The serrated part exerts forces partially axially and partially radially that grip the drill, while the spiral in a 3-jaw-chuck only exerts radial forces. When you apply a radial force onto the serrated part, it has the tendency to splip axially, being a sort of wedge, thus potentially loosening the grip on the part, particularly, if it is not perfectly round. Also, common drill-chucks are not manufactured to the same tolerances (unless you have an Albrecht-Chuck), as 3-jaw-chuck or collets. Source: https://www.mscdirect.com/basicsof/drill-chucks It is better not to perpetrate bad practices, even though you may never experience any problems, say when working on wood or plastics. One day, by way of habit, you will chuck up a piece of metal, the cutting bit hooks and then the whole thing flies around. If you ever experienced how a work piece can be even ripped out of a strong 3-jaw-chuck (as I did once in 30 years working with lathes), when a cutting bit catches, you treat work-holding with great respect.
  2. When you say 'machine' what kind of operation are you referring to ? Depending what your starting material is, there are several options. Assuming that you will be working with sheet material, how thick is the sheet ? One option is to use a circular cutter in the mill. This is a bit like a fly-cutter, but the cutting bit is mounted vertical and the cutting edge aligned so that you can cut pieces with a defined outside diameter. Not sure you find a commercial one for such small diameter, you may have to make one yourself. The second option is to use a 'hole-saw' or disc-cutter, essentially a tube with saw-teeth at the end. The inside diameter is the diameter of your finished disc. If you have a lathe, you can also cut the disc roughly using a fret-saw and turn them down to the right size. To this end you have to chuck two corks, one in the headstock and one in the tailstock and wedge the Plexiglas disc between them. This is the classical method by which watchmakers turned watch-glasses to size. If you have a lathe, you can also start from round stock, face it, polish the face and then cut of the disc.
  3. To be honest, I never use any cutting fluids for turning model parts on the lathe. As pointed out by others, sharp tools are essential to avoid work-hardening. If any material starts to build up on the cutting edge, stop and remove the material or you may ruin your surfaces. Otherwise, I would not be too concerned about working with copper. You may have to try to optimise work-parameters for your special case, so be prepared that the first part may not turn out as desired.
  4. Well, I am sorry to say, but this is bad advice - never use a Jacobs chuck or other drill chuck to hold workpieces in a lathe ! Drill chucks are designed to take axial forces only and the workpiece can work loose, when lateral forces are applied. For safety and precision reasons my personal preference are collets. For larger pieces, of course, one would use the three- or four-jaw-chuck, but try to avoid using hand-held tools (chisels, files, etc.) near such chucks, as they can get easily caught by the jaws.
  5. Thanks, I do have indeed these books. Photographs are rather rare and I wondered, what you might have been able to identify. At some stage I should check out potential French sources for drawings.
  6. Automatic chain-making machines, such as this one (you can see the machine in action from 2:30 forward): The limitation is the tensile strength of the wire,
  7. Just as a sideline: have you been able to collect any information on SMS AUGUSTA and SMS VICTORIA ?
  8. If only the learning curve wasn't so steep ...
  9. Well, sh... happens. I found that I use my ball-turning attachment quite a bit, as I like to have ball handles on my machines. It was originally built for model parts, but mostly got used for making machine parts.
  10. These 'clamps' are not meant to jam the rope (as the modern yacht implement does), but to redirect the pull. For space reasons it would be difficult to have more than two man working a rope that come straight down the mast. In case of yard-halliards it would also be extremely dangerous to work them without any mechanical brake, particularly on a moving ship. If you lead the rope through the notch you can have one or two men heaving down, while one ore more men pull horizontally on the free end; these men then break the rope with the aid of the clamp until the men in front of the clamp have moved their grip higher; and then the same sequence is repeated. If these thingies were brackets for storage, I would expect the notch to face up, not down. Unfortunately, I cannot put my hands on suitable pictures from other ships right now. I seem to remeber having seen such clamps particularly on ships/boats from northern Europe, i.e. Denmark, Sweden and Norway, that were operated with small crews.
  11. Why don't you show the pictures for everyone's benefit ?
  12. I believe that wooden battens were used on ship operating in polar waters mainly. A wet, frozen ratline could break easily. Sailors would not be barefoot under those conditions, but would be wearing seaboots, which would exert heavy wear on rope ratlines.
  13. No. 2 are some sort of fairleads indeed, or half-clamps. When hauling-down a line, it is not so easy to put it around the belaying pin, while there is pull on it; if you hook the line onto the fairlead, the friction reduces the pull and you can handle the end more easily. No. 3 looks like an 'eyebolt' in which a line is secured with a 'stopper knot' at the end; these were use on the inside of bulwarks in pairs to secure rope-ladders for getting on-board. No. 1 is too blurred, but if nos. 1 are the same on both images, than it would be the same as No. 2.
  14. brunelrussel, could you just put up a link to the picture in question ? I also get assorted unuseful results. In addition to the more common vertical machine telegraphs, in the earlier days also horizontal ones were in use. Machine telegraphs on the bridge are connected by wire to an equivalent device in the engine-room. With the lever you set the desired speed/direction, which is indicated to the engineer by hand connected to the lever; the engineer has to confirm your instruction by moving his handle over the hand, which in turn moves the hand on your device; if both conincide the instruction was received and acknowledged. There were also bells connected to the device to attract attention. The 'thing' could also be a rudder indicator ...
  15. Haven't actually heard of the 'fan' as proportional dividing tool before I used a simple paper strip for each frame/bulkhead to take off the circumference and subdivided the measured circumference into an equal number of strakes/planks of calculated (pocket calculator) width, beginning from the middle of the ship. If the plank width becomes too wide at the end(s), you will have to add stealers and vice versa. There are usually certain strakes that run uninterruptedly along the whole length and that have a fairly uniform width, namely the wales. These planks should be put into place first, dito the strake along the keel. The remaining spaces then are subdivided as appropriate. 'Fitting' the planks is a good advice and follows prototype practice. Trying to shape a priori all planks is likely to lead to frustration and poor fit ...
  16. I have been using silkspan for several models over the past 40 years or so, for both, single-panel sails as well as sails made up from individual panels. I used the lightest variation, 14 g/m^2 I think, but think it is only suitable for scale of 1:60 or bigger. The material is thin, but not very tighly woven. For this reason, the 'holes' in the weave need to filled with paint or lacquer. Originally, I used gouache paint, because it is dull flat, but when acrylics became available I used those. Acrylics remain flexible, while gouache is brittle and might peel off. Rather than using white glue for adding the seams and re-enforcements, I used the same paint as for painting the silkspan. The bolt-rope, however, was attached using white glue. For sails made up from individual panels, I prepare the material in a similar way as in the video and then cut strips of the required width. For assembling the sail, I draw its pattern on a piece of cardboard, which is then covered with clingfilm. The panels are glued together using the paint and the whole is let to dry thoroughly. Seams, re-enforcements and bolt-ropes are attached as before. Furling such sails has to be done with caution, as the narrow line of attachement between the panels can come loose quite easily. It has to be said that such sails are opaque and not translucent as some people like them to be.
  17. Not sure 'bitumen', whatever it really is, is a good solution. I know some of the Russians use it, but there are more easily obtainable paints. It appears, as if indeed various washes of paint were used and some wiped off after application. I would think they were oil-washes, but this technique requires a lot of time, because the oils have to 'dry' (oxidise). No intermediate sealers are needed on properly dried oils. A semi-gloss varnish seems to have been used over everything to blend it in. Using acrylics is faster, as they dry within minutes, so you can apply the next wash fast without disturbing the previous one. One can actully apply oil-washes on acrylics as well. They will deepen the colours. The same happens, when you apply a clear acrylic varnish over matt acrylic paints. Very nice 'muleta' indeed, the model shown above.
  18. 'dafi' is not a full-blown commercial tradesman, but rather a fellow modeller, who shares some of his developments. I gather some 'real life' issues, such as a house move, got in his way. I made him aware of the problem and I am sure, he will react soon.
  19. For exactly that reason, that I couldn't find small enough chain, I put off a project for years, because it has stanchions with chains all around at 1:160 (N-scale). What I will be doing probably is to first twist two wires of suitable thickness together, but not too tightly and then twist two strands of those together, but into the opposite direction. This looks quite convincing like a somewhat twisted chain, at least better than any other solution I have come across so far. The thickness of the wire should be the scale-thickness of the wire from which the individual links of the chain in question would have been made. As you can get easily wires down to 0.05 mm diameter, that should cover at lot of needs in small scales. The colour can be a problem, but there are tinned Cu-wires (representing galvanised chain) or black wires at least down to 0.1 mm diameter. I would probably give them a light black wash or some silver dry-brushing to give more plasticity, but be judicious. Leaving details out at HO-scale is not really an option, particularly not chain-stays and the likes.
  20. Absolutely right. I had downloaded Ordnance Instructions years ago and forgot about them. However, they do not contain many drawings of the different types of guns and their carriages. It is mostly a verbal description.
  21. I don't have specific information on US Civil War practices, but the 1840s to 1870s have seen many attempts to improve the controlling and handling of guns as they became heavier. A particular problem was the control of the reoil and balancing the efforts of running the gun out against destroying the recoil in some way. These are two opposing requirements. The recoil on a gun on four-wheeled trucks is partially destroyed by its inertia, partially by the friction of the wheels on their axles, partically by the friction in the running-out tackles, and largely by the elasticity of the breech-rope. An additional problem is, that in a heeling and pitching ship, the direction of the recoil can be rather unpredictable. In order to catch two birds with one stone, a wooden bar with iron re-inforcements was laid underneath the trucks and pivoted on the deck; the truck was lifted onto the bar with an early form of compressor in order to turn its rolling movement into a sliding one with higher friction; also, the bar directed the recoil as it formed a sort of internal rail; the bar obviously could be trained. For similar reason the two-wheeled carriage was developed, as the hind-pads rather than -wheels increased the friction; the two-wheeled carriage was also combined with the above directional bar. It seems that such systems where particularly developed in France. I have some offcial naval artillery handbooks that cover the period from 1850 to the late 1870s, where these systems are shown in great detail. The French used them even in conjuction with 'modern' breech-loading rifled guns before they become supersed by pivoted carriages. Given that the French naval and weapons industry supplied at least the Confederate forces, it is not surprising to see such systems on ACW ships.
  22. Recently I have come across very thin, down to 0.05 mm molybdenum wires that can be had from Chinese sources for little money. Apparently they are used to separate the (broken) glass from the displays of mobile phones ...
  23. Preiser, in my view, makes the best figurines. However, they focus largely on 'railway' scales, namely 1:220 (Z), 1:160 (N), 1:120 (TT, limited range), 1:87 (HO), 1:43 (O, limited range), and 1:22.5 (LGB). There is also a military range for 1:72 scale aircraft. The availability of these figures made me choose 'railway' scales for my shipmodels. They do large sets of unpainted figures that are cheaper per piece and a good starting point for conversions. There also 'academy' sets in various scales, which are naked figures broken down into body-parts that can be assembled to your gusto and 'dressed' using the usual sculpting techniques. An example of using Preiser-figures is given here, for instance: http://www.maritima-et-mechanika.org/maritime/models/botter/botter.html#Creating_the_Staffage
  24. See my response above ...
  25. Tea is acidic and will bleach with time as most natural organic dyes. You would have to look for a permanent, synthetic dye or ink.
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