wefalck

Wonder what kind of wood it is ?

Not much choice, my work-benches have writing-desk height. I am also like the lorry-drivers mentioned in the initial post: as am working all-day at my computer, I also like to sit down for the modelling work. The bench-height I think it is a sort of compromise. For some types of work, you want to have the desk more or less at ellbow-height, in other cases you would like to look down on the work. Watchmakers and Goldsmith have heigher desks and adjustable fore-arm rests for intricate work. In the old days the watchmakers apparently also put the wooden storage boxes of their lathes on top of their stools so that they could look down onto the lathe clamped to the desk. For rougher classes of work I have a foldable work-bench on which I would work standing. usually outside because of the dust.

Does cling-film cling to epoxy resin ? No idea, but if it doesn't, you may be able to use it like 'peel ply' thing. I gather it works squeeze the resin flat, rather than following the contour of the woven fabric surface. Could be worthwhile some experiments.

Coming .... ************** The milling spindle was disassembled and given a thorough clean and generously oiled before being put together again. I also replaced the slotted worm screws that lock the pulley in place with Allen ones. Not original, but easier to operate. Disassembled milling spindle These milling spindles are intended to be operated horizontally and, therefore, have only a simple oiling hole with no cover. In order to ensure adequate oil supply to the upper bearing surface, I fabricated an oilder that rises to the level of the upper bearing. A piece of 4 mm brass was turned down for a press-fit into the oiling hole. Steps in manufacturing an oiler An 1 mm-hole was drilled part-way from this side and a 3 mm-hole from the opposite side. The resulting tube was cut at a 45° angle and the two pieces silver-soldered together to form a 90° knee. From a short piece of brass a cap was turned and bored for a sliding-fit over the oiler. Since the convex knurling worked so well, I applied this also to the cap. The finished oiler Re-assembled milling spindle with new oiler To be continued ...

I have used it. However, somehow the acrylic started to cure inside the tube (which is black plastic) and I had to throw it away - the shelf-life was less than impressive. This defeated from my point of view the objective, because I bought it to circumvent the limited shelf-life of CA glues. I have a large tube of UV-curing cement from the original manufacturers of Plexiglas in the fridge for about 30 years now and it still works ... perhaps should have stored the Bondic also in the fridge. In a way it is rather strange, that these cements are quite expensive, because actually every dentist today uses such UV-curing cements (ok these may be rather high-spec varieties) and the so-called 'nail artists' too. For making these not very elegant fancy false and built-up nails you can get UV-curing acrylics and UV-lamps quite cheaply on ebay et al.

Not sure, what point you are trying to make ? Aren't we talking about prototype paints from bygone areas ?

It is important to keep in mind, which kind of pigments were available at a given time and which ones were cheap enough to be used on a ship. The palette of an artist has always been richer than what was used for such mundane tasks as painting ships. Cadmium-based pigments are a 20th century invention. According to Wikipedia, the potential for the red and yellow Cd-oxides as pigments was recognised in the 1840s, but commercial quantities did not become available until around 100 years later. Today, Cd-based pigments are being phased out again due to the environmental concern over such dispersive uses (for the same reason Cd-based batteries are being phased out as well). However, Cadmium-Red and Cadmium-Yellow paints for artists do not necessarily contain Cd, but are close matches with other pigments. In fact, I think the discussion on the exact hue/colour and trials are rather futile. While iron-oxide reds are rather stable pigments as such, the exact colour of the paint made with them depends on a number of factors, such as how many waters are in the crystal structure of the oxides, where they were sourced, what other components were used in the paint, etc. The best solutions would be to find an ancient recipe for making the respective paints. But even then, there could be significant variations. Also, until the middle of the 19th century, navies gave their commanders considerable leeway in the details of these matters and there was no centralised supply. Colours did not become standardised until after WW1, when for instance the German army began together with industry to develop a colour table that still is in use today, even outside Germany (the 'RAL' numbers). So I would not get too worked up about this as long as you have a somewaht mute and slightly yellow-brownish red.

With only a few days between the many business-related travels, progresss is very slow ... With most of the machining done, I turned my attention to the finish. I would have preferred to leave the parts in their bright, nickel-plated finish. However, the plating on the foot, for instance, was coming off in large flakes. In addition, the parts fabricated from aluminium have a rather different colour. I wanted to have a unified look. Therefore, I spray-painted most parts in my favourite bottle-green (RAL 6007). Masked Primed Painted To be continued ...

I gather, you are talking about the mast-fish, this massive piece of wood the Vikings et al. used to step their masts in. I would suggest to carefully degrease it with acetone or similar and then to (spray-)paint it in acrylic 'wood' colour. This light coloured 'wood' colour can be found in the range of several paint manufacturers, such as Vallejo. The next step would be to apply washes of burnt umbra acrylic with a brush. This has to be done in several layers with a lot of water as a diluant. With these washes you simulate the wood structure, so don't try to get an uniform coverage. You can also use black washes to deepen the colour. If you want to have weathered look, you might give a light wash with white. I have shown this example from my own production in a similar thread a short while ago (apologies for copying it again): Base coat After washes with burnt umber and weathering with white

Messis, could you post a picture of the piece you are referring to ? It seems strange that a kit manufacturer should use solid copper pieces. Copper is expensive as such and not so easy to machine or cast ... Metals (and plastics) can be quite convincingly painted to represent wood. There are various examples here on MSW (including my own ). More difficult it would be to match existing wooden parts. Show us the part and we can give you more detailed advice !

Depends what you are doing, but I couldn't live without a lathe anymore. With a vertical slide you can even do small and light milling jobs. Apart from the hand-held power-drill that costs very little these days, a lathe (with collets) would be on top of my list, if I would start out fresh.

I just bent and soldered the rods and links from brass wire on this 1/60 scale model: The purchase arms were made from three layers of brass soldered together, as they have to sort of clamp around the ratched wheel. It is a bit fake, however, as the ratched wheel does not have grooves on the side into which the brackets of the purchase arms would link. There are also no ratches

As I suggested above, perhaps the administrators start a sort of permanent file, where one can compare the different capabilities and capacities. I agree, for making jigs and attachments for your machines, a bigger machine would be handy. But you will find that is always a 'catch 22' - you always better have a bigger machine for making attachments for your smaller machine. But, how did they do in the old days, when there were no bigger and more precise machines ? Sometimes it just need ingenuity and patience and you can turn out good stuff with smaller machines. As said earlier, if you can't have a range of machines, you have to make a trade-off between your needs. In principle, a big machine is more stable, has less vibrations and, therefore, the potential for higher precision. This, however, requires that it is well-made and well-adjusted. The problem is that adjustment costs time and, hence, money. This is were the Chinese makers cut corners in order to be able to sell their products at competitive prices. Compare a modern-day Chinese mill or lathe with a precision machine of the 1940s or 1950s (the pre CN- and CNC-age) coming from Switzerland. On the latter the slides move like silk in spite of the large masses involved, because the ways have been scraped-in and not just milled. In order to get equivalent handling for working on small parts, you have to opt for a smaller machine - unless you are a master in machine adjustment. BTW, I am working steel on my watchmaking lathes and mills. It is a pain at times and takes a long time because I can only take light cuts, but with perseverance I manage to most things I want to do. The same machine, on the other hand, is ways better than a big Chinese machine will be, on small parts. With careful adjustment, the Sherline or Proxxon machines are almost as good.

Again this is a recurrent discussion ... the epical dock-yard models were made without power-tools available, they were simply not invented then. (Almost) everything can be made with hand-tools, given the necessary dexterity and patience. Power-tools (not the hand-held ones) have the advantage of controlled movements - you work in a Carthesian space and need to worry only about movements along one axis at a time - much easier for many of us. Often power-tools also save elbow-grease, of course. OK, this was rather philosophical. On a more practical level, you need to know what kind of materials you anticipate to work with. Wood, metal, and plastics all have quite different machining properties and require (often) specific tools. Wood requires much higher cutting-tool speeds than metals. This can be a serious limitation, when thinking of using a metal-lathes for working on wood. Most mills run only at around 5000 rpm, which is too slow for the small cutter you are like to use. The only mill I know of that has rpms adequate for wood is the smallest PROXXON. There you run into capacity problems, because the slide travels are rather limited. It would be ok for making small parts, but could pose a problem, when you want notch keels or something like this on largeish models. There will be alsway a trade-off.

This seems to be a recurrent topic. Perhaps the administrators could/should create a permanent space, where the pros and cons of different types (not makes !!) of machines can be laid down.

More capapable in what respect ? Size ? But then you talk about capacity, rather than capability.

'Securing' a knot with glue/varnish means that you overcome the springiness in the thread that has a tendency to unravel knots by some sort daub. This something very different from glueing two materials together. In the first case the process of knotting forms an interlocking, mechanical connection, that is not there in the second case. When your knot does not form this interlocking connection, then something is wrong with your knot. Seamen's knots are always secure. I use a fast-drying clear varnish for the purpose that is very similar, in fact, to nail-varnish. The advantage of varnish is that you can loosen the knot (or belaying) again by putting a drop of solvent on it. Comes handy when you discover mistakes, or when you need to tighten/loosen something.

A different, though perhaps somewhat more expensive route would be to have them etched. Perhaps there are other parts you could do at the same time. Perhaps you could share the cost with other builders by having several copies done. Drilling into sheet brass can difficult with helical drill can be difficult, as the standard drills tend to 'catch'. There are special drills for brass that have a steeper helix and are ground differently. Another option are spade drills as traditionally used by watchmakers for the purpose. They can be obtained from watchmakers and jewellers supply houses. Watchmakers also used to make spade drills themselves, but this needs a bit of practice (which they would have acquired during their apprenticeship).

Trying to keep up standards **************************************** Some time ago I purchased a 12V motor from a Chinese source that is supposed to run at a nominal speed of 3000 rpm. Considering is length of 71 mm and a diameter of 51 mm with an 8 mm drive shaft I expect it to have sufficient torque for the purpose. The data given by the seller were rather cryptic. The mounting of the motor caused me some head-scratching. The original intention was to use a bracket similar to the one used on the lathe toolpost-grinder shown below as the mock-up. Self-contained drive unit as used on the toolpost-grinder This would have resulted in a self-contained drive unit. However, the motor would have fouled the cross-slide, when the y-slide is fully run out. Making the bracket longer would have solved this problem, but I was afraid of the vibrations this long lever might transmit and the distortions to the y-slide. Another possibility would have been to mount it upside-down over top of the y-slide, but this would have raised the centre of gravity of the whole machine considerably and transmitted vibrations to the system. In the end I make, for the time being, a simple bracket that uses the two screws with which the extension of the y-slide is screwed down. Motor mount The lathe and grinding spindles were meant to run at maximum speeds of around 4000 to 5000 rpm. Therefore, a slight stepping-up compared to the motor speed would be permissible. As the motor bracket does not provide for any adjustment of the belt-tension, I copied the pulley on the grinding spindle for use as a motor pulley as exactly as possible. It will be put upside-down onto the motor, so that the belt can be shifted for stepping up (1 : 1.4) or stepping down (1 : 0.7) speeds without the need for adjusting the tension. Most of the speed control will come from the electronics in the power-supply. The pulley on the grinding spindle has a 75° V-groove for 3 mm round belts. A V-groove can be cut by either setting over the top-slide, or using a pointed tool with the appropriate angle. I had to grind a HSS-toolbit with this angle, checking it against a template. The two grooves were cut using a stepping method. Cutting it full depth would not be possible. I order to ensure concentricity between the pulley-bore and the groove, first the step in which the set-screw is located was turned and then the piece turned around for drilling/reaming the bore and cutting the grooves in the same set-up. For cutting the grooves the pulley was supported with a revolving tailstock centre. Steps in machining the motor pulley The finished moto pulley The two drive pulleys To be continued ...

Breaking 2 mm drills ? Sounds like brute force ... OK, done this as well, but it was in steel ... Personally, I prefer collets. Don't know the Dremel products, but the Proxxon ones are pretty good concerning run-out. The tightening nut is smaller than the chuck and, therefore, you can see better what you are doing.

I found this question - which seems to pop up from time to time, a rather odd. Divide the real size of the hole you want/need to make by the scale - in your case 48, and you will get the diameter you need. Normal CV or HSS bits come in 0.1 mm graduation, but can be also obtained from watchmaking suppliers and other speciality suppliers at 0.05 mm intervals. In practice the 0.1 mm step should be sufficient. Sizes below 0.3 mm are not so easily obtained and are rather fragile. Watchmakers suppliers also have drills with straight flutes that are much more rigid, but rather expensive. Another option are surplus carbide drills that are available on the Internet at reasonable prices down to 0.1 mm diameter. Beware these are even more fragile than HSS drills and may not be suitable for hand-held drills.

Thanks again, gentlemen *********************************** As for the other dial fabricated earlier, a pressure pad provides for an adjustable friction stop. The outside rim was also given a treatment with the concave knurling tool described earlier. Knurling the rim of the dial The engravings on all dials were filled-in with black paint and when the paint was dry, the dials were slightly rubbed-over with fine wet-and-dry paper to leave crisp black engravings on a satin surface. The finished dial at its place Finally, the cleaned cross-slide was re-assembled with the new dial. Re-assembled cross-slide To be continued ....

It was a joke ...

'Red Oxide' paint should be the right track. Lead-based pigments have been around for centuries, but were much more expensive then the iron-based pigments. You have to turn the lead first into the oxide, while the iron-oxide only need to be refined. I would think that there was a certain variability in the hue due to the variability of the natural pigment. Howeever, it should be probably more brownish than orangey. Cadmium-red (which does not contain Cd anymore today) would be too bright. I would assume that the paint was based on lineseed-oil, rather than on animal oils. Lineseed-oil, the classical verhicle for 'oil paints' is a drying, i.e. oxidising, oil.

Excellent crimping tool for the metal rim around the shields !