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bricklayer

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  1. Jaager I referred to the image in post #4. I called the patterns No. 5 to No. 10 bulkheads. The words moulds or formers may be more suitable than the word bulkheads. I know the original meaning of the word bulkheads that devide a hull into several watertight compartments. But the word bulkhead is widely used to replace the word mould. Strictly spoken one word isn`t interchangeable with the other. Dziadeczek traced some lines in red and green. I think that two adjacent green lines define the thickness of the pairs of frames (bends) or the thickness of the moulds. The red line in the middle is the actual station line. The moulds No. 5 to No. 10 don`t show the corresponding station lines. They only show the adjacent green lines, the fore and aft of the bends or moulds. I have to admit that I didn`t read Tony`s initial post thoroughly. I thought that he intended to add further moulds, only. E.g. mould 5 1/2, 6 1/2 and so forth. Now I understand that he wants to transform the POB drawings into POF ones. Are there drawings of La Jacinthe other than the ones that Boudriot drew? A set of drawings that shows all timbers, the whole interior? If not then I wonder how to determine the dimensions and the location of the joints of scantlings. That`s a true challenge. Michael
  2. Tony The Station lines themselves aren`t drawn on the bulkhead-templates. If they were drawn, then they`d run in between the inner and outer contour lines (fore and aft lines) of the bulkheads. That`s because the station lines are located at 1/2 the thickness of the bulkheads. The same applies to hight of bulkheads. There`re dotted lines that run parallel to the deck camber. The dotted line indicates the rear, invisible edge of the bulkhead`s deck camber. Two orthogonal views should be suficcient to define the shape of a hull. Station lines + water lines or station lines + buttock lines or water lines + buttock lines. Taking into account a third view may lead to confusion and uncertainty because the views of hand-drafted plans don`t match properly. If the lines of different views don`t intersect, then there`s nothing but guessing and re-fairing the lines. Which one is most true? Station lines, water lines or buttock lines? Once you know how to operate a 3d modeler like Fusion 360, Rhino 3d or Delftship then it will provide most reliable hull shape and lines. Their analysis tools show how smooth and fair lines and surfaces are. Curvature graph for curves and gaussian curvature, shading and zebra striping for surfaces. I modeled the "sea bright skiff" published by John Gardner in Delftship. I strictly followed his table of offsets. The lines, which each represent the upper edge of a strake, look horrible in both top view and longitudinal view. These lines are neither water lines nor buttock lines nor diagonal lines. They show the run of the strakes. The lines and the shape of the hull may satisfy you. After having applied those tools mentioned above they won`t do anymore. It ain`t easy to determine that the fairing or lofting job is completed. Major alignment is done quickly. Minor alignments may take an eternity. You`ll find an appropriate way as you did in your previous builds. I like both boats that you already completed by means of Ancre plans. It seems that the Allege was a real challenge. Michael
  3. Vaddoc The two sample strips that you layed loosely on the hull look good. Their texture and colour is sufficiently uniform. You`re a woodworker. Wood varies from strip to strip and even within a single strip. So what. It`s craftsmanship and accuracy that matters. Your`s is marvellous. Oil it or coat it with clear acrylics, shellac. Just don`t stain it. Stain will uncover the filler in the gaps rather than to hide it. Michael I think that any of the coatings previously suggested here is suitable.
  4. Gaetan Over here in Germany the public electricity network is terminated 3ph 400V, L1 L2 L3 N PE. I think that it`s the same in the Netherlands, Belgium and France. It just isn`t availiable in all rooms of the buildings. The outlet for electric stoves is always 3phase. If I had acces to a 1ph outlet, only, then I`d use a proper VDF. It generates 3 phase output at variable frequency usually between 0 and 400 Hz. Some 20 years ago our rotary phase converter died. It had driven an internal vibrator for compacting concrete. I`m grateful for it`s dead. It`s successor with build-in VDF is lightweight and makes less niose. There`s just one disadvantage of VDF`s. They emit electric noise. Kind of high frequency square waves. So proper filtering and shielding is required. Michael
  5. Hi Scott The paint on the hull of your model should resemble white lead paint. https://en.wikipedia.org/wiki/White_lead Unfortunately its use on vessels is mentioned in a single sentence, only.
  6. There`s an Englishman who seems to be laser-addicted. You`ll hardly find a better teacher. It takes several hours or days to watch and listen to the videos attentively. After having done so you can take a sound decision whether a laser cutting/engraving machine is the right tool for your workshop or not. Be aware that those cheap chinese machines are class 4 lasers. If you want to operate a machine that complies to european and US laws, then you have to get a class 1 device. Only a class one device guarantees save operation. The DC excited laser tubes have a limited lifetime that varies from some hundred to some thousand hours. If the cutting job requires 50 to 60 W power then you`d buy an 80 W tube. The CO2 in the tube degrades less when it`s runs below maximum power rating. The laser tube has to be water cooled by means of an external chiller and tubing. There`s got to be permanent air flow through the nozzle. Fumes and smoke have to be extracted from the machine and led outdoors with a blower or led into a three or four stage filtering device. It takes some effort to run a laser cutting/engraving machine save and properly. Bill, I don`t want to scare you. I advise to obtain knowledge before to take a decision. A laser cutter makes sense, only, if you create the cutting/engraving files yourself by means of any software that generates vector graphics. If you depend on third party files, only, then you`re lost. My incomplete contribution to this subject. Michael
  7. If someone gave me one of those Sixis or Aciera (watchmaker?)-machines, then I`d put it in a sealed showcase to protect it from dust and humidity, I wouldn`t dare to touch it without wearing cotton gloves. If I did any damage to such a machine while operating it, then I`d have seven sleepless nights in sequence. I think that one shouldn`t recommend these swiss precision tools to a beginner. Michael
  8. Vaddoc I`d plank the hull entirely before to apply force to the stem post. The assembly of molds, keel and stem looks too fragile to me to do any machining on the stem post at present state. I`d glue the planks to the molds and stem one by one rather than to attach them all with screws temporarily. A glued or welded structure is more rigid than a screwed, riveted or nailed one is. If the stem post is tapered prior to sanding or scraping the hull smooth, then minor scratches on the planks won`t do any harm. That`s my opinion. I may be right or wrong. Michael
  9. Ron If you want to run the drum sander at high rpm with low vibration, then you have to balance the drum, I suppose. There should be equal distribution of mass around the longitudinal axis. See balancing vehicle`s wheels. The drum should be balanced with abrasive paper mounted, like a wheel is balanced with tire mounted. Nonetheless I like your simple design that you can modify according to your needs. What about a conveyor belt to ensure constant feed of material to be sanded? Michael
  10. Point, I just found a link to a free nesting soft on a german forum for cnc-machining. https://deepnest.io Yet I havn`t installed and evaluated it. I read the brief description, only. I think it`ll do the job. I don`t know whether parts are rotated during nesting or maintain their original orientation. Rotating them may not be desirable because it changes the run of wood grain. Michael
  11. Eberhard I think that hyw - unfortunately he didn`t tell us his name - built the winch strictly according to the drawing released by ANCRE. So there`s got to be a different way to lock the gears to prevent the winch from spinning reverse. A gear that`s shaped like a circular saw blade with a pawl, that engages at the steep side of rhe teeth, is self-locking indeed. But I think that self-locking of the winch on this particular ship is obtained in a different way. Moving the long two-sided lever seems to spin the winch. Perhaps friction prevents it from spinning reverse. E.g. you turn a rotary table by turning it`s worm gear. But you can`t turn the worm gear by turning the table. It`s self-locking without a pawl to be engaged. Michael Marvellous work on Gemma.
  12. Hi Spyglass I ran into similar trouble when I sanded a hull. There`s a remedy, that works fine. It`s two layers of cardboard laminated to the inside of the hull with pva. Note the variation of plank thickness along it`s way. Even in those areas, where the sheer strake has half of it`s original thickness, only, it`s sufficiently rigid. I applied pva glue to the cardboard abundandly. When being attached to the hull the excessive glue fills the gaps between the planks and provides contact on the entire surface. The cardboard was pressed firmly against the plank strips. Michael I
  13. Hello Carl What about domestic cheese like edamer and gouda. don`t they contain enough gas bubbles? We should return to the original topic, I think. And I think, that you`re the one, who lives closest to my home town. I live some 20 km south of the place, where the rhine divides to waal and oude rhin. Maar ik spreek geen nederlands. Michael
  14. Hi Tony You got to divide the hull surface into longitudinal sections, first. They represent the plank strakes. Each strake is a sub-surface on it`s own. Then you apply the develop or flatten command in your CAD application. This command doesn`t just project the selected entity on a plane. Rather than that it straightens the entity. Be aware, that the thickness has to be taken into account. By default surfaces don`t have thickness in virtual modeling. The development command may only work, if the surfaces (plank strakes) are straight or flat across their length. So the station lines should be polylines rather than arcs or curves. Development works best on stations, that have knuckles and straight portions. I`ve never done it myself, but I know that Rhino 3d, the CAD I use, provides this feature. I can hardly await to see more pics of your Chaloupe built. Michael
  15. Hi Ben Your second approach to lofting the hull seems to be the right one. Now you have a single surface. Before it looked like a "pile of patches". There`s no bad intentions in telling you that. Does fusion 360 have analysis tools other than zebra striping? Can you apply gaussian curvature to the hull? It shows the amount of curvature all over the surface in colours. It shows the direction of curvature, too. Inward or outward. Is there a tool called curvature graph in fusion? It`s a set of "needles", that point perpendicular to a curve or surface. Or rectangular to an imaginary tangent at a given point. The length of the "needles" indicate the amount of curvature. In your post #31 two control points are close to one another. At midships. One of the points is located inside the curve. Does the curve bend inwards over there? Is there a hollow? I`m curious, because I lofted hulls in Rhino. Finally I discarded those lofts. After having applied analysis tools, none of them satisfied me anymore. My findings are not meant to disencourage you. Not at all. I`ll follow this thread. Michael
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