wefalck

There has been a long break in this project, caused by a virus-induced vertigo that began in the middle of March. It made it impossible for me to focus my eyes on small things and to do any work in the workshop. Recovery was slow and could not go back to the workshop safely until a couple of weeks or so ago ... ******************** Two of the ventilators of the crew-quarters in the forecastle have the hollow chain-bollards as their base. These chain-bollards are used to relieve the chain-stoppers when anchoring or being moored using the anchor-chain. They have a couple of protruding 'noses' that keep the turns of the chain apart, so that the links do not wedge-in each other, making it impossible to cast-off the chain. Initially, two rims were turned on a piece of round brass and these rims then were reduced to the 'noses' by round-milling on the dividing head of the micro-mill. The base was also milled rectangular, as required. The ventilator was fabricated seperately, as the bollard will be painted black, while the ventilator will be white. The set of ventilators is now complete, but they still need to be drilled for the handles by which they are turned. For this I need to fabricate an adjustable support for the dividing-attachment of the micro-mill so that they do not give, while being drilled. To be continued soon ...

Yes, that the classical method. But you still have to shape the sheave, so that the rope doesn't make a bent. I have done this on blocks down to about 2.5 mm length, where the sheave is around 0.4 to 0.5 mm thick. But, try to do this, if the sheave is only 0.2 mm thick ... But we are veering off the subject, which is about designing blocks for printing and not finding alternative ways of making them.

As I said, I don't have a lot of CAD-experience. Some packages may be able to generate the complex curves. Generating the shape of the sheave, of course, would not be a problem. Making any number of 1 mm-blocks from wood would be a challenge in principle, including drilling the needed 0.2 mm holes, and it would be very difficult to score a 0.2 mm groove into the sheave in a way that leads to a realistic run of the rope. Not sure, how I would hold them to shape the outside. They are also too small and light to round off in a tumbler. Making one would be feasible, but not many of them. BTW, buying means that someone else can make them - I would be ashamed the to admit, that I couldn't make them myself

Acrylics don't creep due to the rigid cross-linking of the polymer during curing. That the nice thing about Plexiglas.

I am not an artist, I am a scientist Forgot to say something about 'glaze': in artists's parlance thess are thin, (semi)transparent coats of paint. The Old Masters built up their paintings from numerous layers of glazing, which is why the colours are so deep and luminous. Glazing with oil-paint takes time, because each coat has to dry (oxidise) or otherwise it will be dissolved by the following layer. Each coat may take at least a week. With acrylics, the 'drying' takes minutes, but they are not as luminous. There are also 'wood-glazes', which are varnishes with some dye or pigment in them. When they are organic solvent-based, you normally can apply only one coat, as the next coat would dissolve even dried previous coats. If they are acrylics-based, you can apply as many consecutive coates as you like.

I have been toying with the idea of 3D-printing rigging blocks for years, but never got round to master the basics yet, that is 3D-modelling. I gather, one would need to model the basic shape first - for which one needs to refer to period references for getting the proportions right, and then add the roundings etc. with some sculpting software. The nice thing is that one can model the shell and the sheave separately and then combine them for printing, as the sheave would not need to rotate, of course. This would lead the rope through the block without the sharp bents one sees so often in simple wooden blocks. I don't think extrusion printers would be suitable for printing really small blocks, I would go for the technique that selectively cures acrylic resin with pulses of UV-light. With this, one should be able to print blocks down to a length of about 1 mm. The problem will be the bores, but one can always open them up with a drill, if needed.

Directly ? Sure, but then, when you mess up, you have to begin all over. I think it is easier to paint on a flat surface, like the decal sheet. You can also print the pattern to be painted on it before, as a guidance for the shape and spacing.

Using etched parts can indeed simulate carvings or mouldings. I have the feeling that the metal re-inforcements where actually let into the rim, rather than being applied on top of it - they could easily rip of during rough handling and could also cause injuries. I think they would be flush with the surface. At least that is what I have seen on museum pieces. While not looking quite brass-like as the real brass, imitating the re-inforcements with decals might be closer to the real thing. Once could make one circular decal for the rim, rather than applying individual tiny ones.

I had indeed looked into the possibility of having the wheel printed in 3D, but the required materials diamaters push the current technology to its limits. Besides, I have not mastered yet the 3D-modelling techniques that provide the input for the printing process. I don't really like buying-in things that I think I can do myself - it's like dodging the challenge

Pat, I was rather thinking of fabricating something from hard wood that would fit onto the bench. One can make the moveable jaw in two pieces, the main part flush with the bench-top and then having the holding actual jaw plugged/screwed onto the top of it. In this way, the jaw doesn't get into your way when not needed and you can have differently shaped jaws according to needs.

The keyword to look for is 'wood-graining'. Used to be a trade of its own until about WWI. A lot of faux materials were in vogue from around the middle of 19th up to WWI, including imitating wood, bamboo (e.g. on cast-iron garden furniture), and marble. I have a modern book on the subject. However, I am not sure that I would use these techniques on such a small item. It is not very likely to see wood-grain on a steering-wheel, which would have been fabricated from the best quality mahagony probably. The different section of the rim may have had slightly different colours though. I would just apply glazes. Some people also use artists' oil to good effect for this, but drying times are very long, particularly between coats. When you use acrylics, the next coat can be applied quickly and does not dissolve the coat underneath. From the photograph I see that the wheel did not have a continuous facing of the rim in brass, but single re-inforcements, where the spokes penetrated the rim. So my idea of masking doesn't work in this case. One option to reproduce the re-inforcements would be to paint their shape in brass-paint on some transparent decal material and then apply them as decals. One of the next jobs for me to tackle on my SMS WESPE-project will be indeed to make two sets of double steering-wheels - the wheels will only have a diameter of about 10 mm and the spokes will have to be 0.3 to 0.4 mm thick - causes me some head-scratching, but I have ideas ...

I would spray-paint the wheel with a sand-cloured paint - there is also Vallejo-paint called 'wood' I believe. Next you can brush on e.g. some mahagony lacquer, either water- or organic solvent-based. Do this in thin layers to have control. You can also mask e.g. the rim, if the wheel had a brass one.

Hi Pat, Indeed completely misunderstood you. However, perhaps the design of these toolmakers vises could perhaps be adapted to your problem. Have a block running in a slot in the bench and tie it down with a bolt that screws into round bar, which in turn is pushed into horizontal holes in the bench.

Thanks, I thought so, but wanted to have it confirmed. Good thing that I don't have this book

This is an image of a 19th century boeier, which were rather different animals from the subject of this build-log. These boeiers were used for commercial passenger traffic around the (Noord-)Holland and also as (private) pleasure boats. For those, who read Dutch, there is a comprehensive book on the subject with a lot of lines drawings etc.: VERMEER, J. (2004): De Boeier.- 528 p., Alkmaar (De Alk & Heijnen Watersport).

What you mean actually by 'set into and flush with the top of the bench' ? Not sure then that would help you, but you may want to look into so-called toolmakers insert vices. They don't have a horizontal spindle, but the loose jaw is tightened with a bolt from above. The bolt screws into a horizontal bar that is held by either notches in the underside of the vise, or the bar goes through horizontal borings (in this case you need access from the side). They came from 25 mm jaw width upwards. Here a sample picture: I have several of them for use on my machines. It is strange, but the brand name Zyliss conjures up in me not exactly the image of a precision tool, as the company seems to be mostly known for its hand-driven kitchen implements, such as meat-grinders, onion-choppers, salad-spinners, and the likes ... I have seen these bench-vises, but thought they were made from cheap die-cast zinc.

BTW from which book did the contested drawing actually come from ?

I don't know the book, from which the drawing came, but looking at made me scratch my head Mechanically it doesn't make any sense ... I was going to comment that whipped blocks, i.e. from which the running part cannot be detached, would be rather uncommen in real running parts of the rigging. In case the running part becomes damaged from use, one would have to unstrap the block and replace the whole splicing, serving etc., rather than simply replacing the running line. On backstays it would, however, make sense, as the movement of the running part is only limited, with not so much wear. For blocks with eyes at both ends, I think there would be long splice alongside the block and the eyes tied off with yarn at both ends. I think either Lever or Steel have drawing that shows that, didn't check.

Well, you partly answered yourself your question: the key point is particle size or rather the absence of particles. For this it is important to recall the difference between the different media: Paint essentially is a suspension of pigment particles in a solvent and film-formers; the objective is to create a covering layer of paint made up from the pigments and the film-formers; in the case of acrylic paints, the acrylic monomers will also undergo some sort of chemical reaction, by which they cross-link to form a layer into which the pigment particles are embedded. Dyes are molecules dissolved in a solvent; the dyes either adsorbe to the surface of the material or may undergo also some chemical reaction with the material to be dyed; in consequence, they do not form a continuous layer on the surface of the materials. Inks can be either paints or dyes; in the former case they are called pigmented inks; acrylic inks fall into this category; like paints they form a more or less continuous layer on the paintes surface albeit their particle size is much smaller than in paints, allowing them to be used with e.g. pens. Simulating the tarring etc. of ropes presumably can be done with inks, as on the prototype the tar only partially penetrated and part of if acted as a dye and part of it as a paint. Paints on the other hand would stay on the surface and form a layer. I gather paints could be used to simulate the tarring with coal-tar of later periods, but would be less suitable to simulate applications of wood- (Stockholm-)tar.

The separator is a good idea - it is easier to search through a small pile of debris than across the whole workbench (which unlikely is as clean as in a clean-room ). I gather the rentention capacity would depend on its length, so a long, narrow jar might be safer than a shallow one, or you would need to put a bit of foam in front of the internal suction pipe.

I have not been suggesting that a 1/72 or 1/48 scale resin model would be the solution for your problem.

If you have CAD-program and the skills to go with it, you could develop a virtual 3D-Model and have it printed ... trawling the 3D-printing companies, such as Shapeways, might also be worthwhile. Wasn't there even a Chris Craft with an egine here on the forum, or was this a Riva ? I have been tossing with the idea of a model of an early run-about or speedboat with one of those huge marinised surplus aero-engines that they used in the 1920s or so. There various WWI resin engines in 1/72 and 1/48 scale available.

One probably needs several sizes of vise ... the best small bench vises are those for jewellers/clockmakers, but they can be very expensive, even second hand. Brands are Bergeon, Leinen or Boley over here in Europe. It is a good idea to have one that can be turned. For precision work a jaw width of 40 to max. 60 mm seems a good size. If you cannot buy one of the above brand ones, it is always a good idea to check the one you intend to buy, whether the jaw close neatly and parallel. There is a lot of cast-iron scrap being flogged to undiscerning customers. For really small work, you might also want to look at so-called toomakers insert vises. They come as small as 25 mm jaw-width and are (usually) very precise (at only around 35€). They are mainly used in EDM-machining, but come hand for other purposes. You can use them on the bench, but may have find a way to fix it to the bench - they have normally two M4 threaded holes at the bottom.

I kind of suffer from the same disease: not enough space ... one soution I decided upon some time ago was to tackle only projects that can be drawn on an A4-sheet ... for bigger projects I would scan the plans and correct them for distortions as mentioned above. You then can print out (again checking for distortions) as many working copies as you need. For individual parts I usually print them out even at a magnification (say 10x) and add measurements by hand. This allows you to correct for additive errors due to line thicknesses etc. The overall part has to have the correct size and you can correct your measurements to fit into the overall size. In other words, you arrive at a sort of graphical cooking-book from which to work. I have either the sheet flying around my work-table or fix it to light-weight clip-board.