wefalck

These packets or 'postjagten' were used on established routes around the Baltic to transport passengers and mail. At that time what is today known as the Vorpommern region of Germany was under Swedish administration (from the Westfalian Peace Treaty in 1648 to the Vienna Congress of 1815, when it came to Prussia). There were regular connections between Stockholm and other Swedish ports on one side and for instance Stralsund on the other side. These sloops were heavily canvassed for speed and owing to the square-sails presumably required a quite large crew. A much larger one than the comparable commercial 'jagten' had, that were usually sailed with only three or four hands, including the master. As to the tiller, I would assume that it was operated with the aid of tackles, rather than directly by hand. There are a number of drawings of similar 'postjagden' in the archive of the Danish naval yard in Copenhagen: https://www.sa.dk/ao-soegesider/da/other/index-creator/40/3353816/17149179. They may provide additional useful detail. Check out the drawings with these archive nos.: G-4059 to G-4064.

To me these boats look quite 'British'. For instance, Yarrow and Thornycroft not only built boats for the RN, but seem to have a big export business. I believe by 1900, the Russian industry was quite quite capable to produce such items of equipment, but often under design licence from the UK, France and Germany. I think many, if not most, navies contracted out the building of boats to private boatyards, often specialised in such things. The specifications were standardised and products were inspected by naval officers before being accepted for delivery. Boats to some extent were 'consumables' and the navies kept stocks to be able to replace them quickly - see e.g. the still existing boat-sheds in Chatham.

Very crisp and professional work as usual !

Hey guys, this is building log on the GERMANIA by Keith. Perhaps we should start a new thread on how to blow up things

I would also look into some serious dust protection measures for the (ball?)bearings. Ball-bearing don't lake abrasive grit too much ...

The worst of all was our chemistry teacher at school. He was a poor experimentator and things never worked out as they should have. One day, he wanted to demonstrate the exothermic reaction of 'thermite' (an iron oxide and aluminium metal powder mixture) and did this on the tarmac school-yard - he ended up being summond to the director of the school for burning a big hole into the yard ...

My father was a chemist and I had subsequently more complex chemistry sets ... at that time it was also quite easy to get chemicals, there was a 'technical' drug-store right next to the main department store in my university town. The more dangerous thing were those experiments we did 'off the record', such as trying to make gun-cotton 🥴 ... my father had a text-book on explosives making and testing ... I also made black-powder, but it was not very good. Today I would become arested as a budding terrorist, if I would try to buy the ingredients.

I gather then you were a couple of steps up in the flow-sheet from me. With the British Geological Survey (1987-1992) I worked on contract research for BNFL, NIREX and the EU on the various shallow and deep disposal programmes. Even though I had signed the 'official secrets act', as an 'alien' they would not let me onto the Sellafield site, where we had a research project going on. As I was mainly there to 'computer model' radionuclide migration in the environment, fieldwork was only a minor part and 'entertainment' for me. We had some good trips around the country side on tax payers expenses (but don't tell anyone ...).

Sellafield or Dounray? When? In the late 1980s/early 1990s I worked on the UK RWM (NIREX) programme for BGS.

As there are hundreds or even thousands of plastics around I tend to check their persistance against solvents, alkaline or acid solutions in Wikipedia. There is usually a section or table on this in the Wikipedia on the plastic in question. If not Google helps to find other resources. Acetone dissolves e.g. polystyrene and acetate/celluloid, which is why it is often a constituent in the respective cements. It is usually sold in either metal containers (for mechanical resistance) or in HDPE (high-density polyethylene) bottles. (HD)PE is chemically rather resistant, which is why most chemicals and many foodstuff are sold in it. I am afraid, Nylon is pretty resistant chemically. I think the only solution is to burn it off. And one piece of advice (from a sort of chemist): never mix two chemicals, neither liquids nor solids, unless you really know, what you are doing. There are stories of housewives nearly killing themselves with chlorine gas, because they mixed two toilet cleaning products ... it seems that this subgroup of the population is particularly nonchalant in using chemicals (gues how I know ...).

Ah, Pat, I didn't realise that the Byrnes is one of those 'end-less' machines. That makes things indeed more complicated. However, as you obviously will need a lot of LH rope, it may be worthwile to reconfigure the machine.

Why doesn't the Byrnes ropewalk work not so well for RH rope? I would have that that this is just a question of cranking into the opposite direction. However, I am not familiar with this ropewalk. One may need to unravel commercial thread, if the twist is the 'wrong' way around, but that is not too difficult usually.

... then you would wish, it wasn't - it would cling terribly to your tools and these are not so easy to demagnetise.

The subject of the colour of copper-plating seems to popping up over and over again. In seawater, copper turns to a dull brownish colour. It is only out of the water that copper turns green - if there is sufficient sulfur dioxide in the air.

Could it be that such gratings above the stove were clad on the under- and inside in sheet-metal of some sort to protect the wood from heat and the steam? You wouldn't see this from above and modellers would not (haved) reproduce(d) it.

Yep, lofting cant-frames on paper or in a 2D-CAD is not so easy, particularly providing the addenda for fairing, when cutting them out of wood sheet.

Watchmakers and jewellers indeed use aprons. Watchmakers generally use cloth, while those of jewellers are made from leather. The latter clip to the underside of their workbenches, so that they can recover precious metal filings. It also protects them when silver-soldering. I have been wearing aprons in the workshop for decades. However, I found that small pieces mostly either bounce off, or just drop besides ...

Pat, are you making your own rope? If so, you could try some 18/0 fly-tying yarn (I found the Danish Veevus a good brand), which should you get down to 0.1 mm or even below, if you split the two-ply yarn and make two lengths of three-strand from three lengths of the two-ply yarns.

Ah RR-apprentice at work - love this filing-button work, that shows the toolmaking approach. I could think of two uses for these strops at the end of the boom: either they are some sort of footropes (well HSE rules apply, when you have a professional crew, but it may depend on the country of registration) or they are sort of bridles to grab and help the boom shift, when going through the wind.

Looking good, Pat! Just wondered, whether you couldn't have used some solid round brass, turned down the OD and drilled/bored out the ID to fit? When parting off with a saw, I would do this on the lathe, running at low RPM. I usually make a first cut with an cut-off tool to provide a guide for the saw and then finish it off with the latter.

Well, now you have the link to maritime subjects In fact, quite a few colours i.e. pigments were available, sometimes since antiquity, but cost variied considerable. Lamp-black was among the cheapest, easy to produce and intensive (meaning the amount of pigment needed to achieve a good coverage) pigments. Earth colours (e.g. the various types of ochres, ranging from pale yellow to a blueish red) were also cheap. White lead is/was also cheap and had a good intensity. Other lead oxides (menninge) were used extensively as rust protection. Chalk or lime is even cheaper, but chemical reasons cannto be worked into oil-paints. However, it was intensively used as white-wash, as lime solutions also have anti-microbial properties (not know as such at the time, but white-washed environments where 'healthier', hence its intensive use on shipboard, hospitals, private houses etc.). I have been researching paints for (German) later 19th century warships quite bit, and it seems that well to the end of that century, paints were delivered as their components to the ships, that is the pigments, the binder (oil), and thinners separately. Paints were mixed up by weight and volume of the ingredients on the spot and would not have had a long shelf-life. Certain paints, however, such as anti-fouling paints, became commercially available from the later 1860s onwards. This means that the actual shades of 'battleship'-grey or yellow for masts and funnels could vary from ship to ship and even across a ship. Grey for warships became gradually the rule from the mid 1890s on, but the greys of the different navies differed a lot. Machine tools were almost always painted black until the end of the 19th century, particularly the bigger ones. Then, indeed, grey became more common to light up dark workshop and to see better what happens. Precision machinery then often became painted dark green or other shades of green. In Germany, for instance, the standard colour became 'Reseda-green' in around the 1930s, almost until today. Some (precision machine tool) manufacturers, e.g. Schaublin, Bergeon etc., choose specific standardised colours, such as blue or pale yellow.

I would like to echo this! And I could have done with a longer log Steam-engines were presumably painted in darker colours (typically dark green, brown or red/vermillion, or even black) because one would not see oil-stains on them so easily.

... which means that you have to make the patterns first. As the colleague only needs one of each, he might just stop there

That’s an ingenious way of making boat-shells. I would not have thought of using galvanoplastics for that. However, as you have the set-up already for e.g. the ventilators it’s logic.

The machine begins to look like one 👍 The fishbelly-shape serves to stiffen the link against buckling, when longitudinal stress is applied, and to reduce the moving mass at the same time, compared to using the same width all along. Reducing these masses is important, as they have to be accelerated and then decelerated at each stroke. At this time engineers had only limited means to calculate the static stresses on such parts and basically no means to calculated the dynamic stresses. As you can often on say connecting rods in steam-locomotives, the interior has been thinned, leaving basically a bar on both sides with a sheet of metal spanned out between - effectivelly like a fishbelly girder-bridge. Such parts would have been moulded and cast. A question: why did you turn the pivot-pins and did not use precision ground 1/8" rod and ream the holes to size? And another observation: I tend to start-tap holes in the milling machine with head in the same position as for drilling the hole. This ensures verticality. I utilise the backlash on the vertical spindle, lowering the head to the bottom of dead move, advance the tap perhaps half a turn, then again taking out the backlash, and so forth. I usually do this only for a couple of threads, until the tap has securily grabbed, and finish off tapping away from the machine.