wefalck

Only after my last comment, shortly before going to bed, I noticed that there were felt-washers between the bobbins and the frames. While such a machine is an interesting engineering design challenge, I think there are too many degrees of freedom to make it really practical - unless you go into industrial production. Many of these variables have to be re-adjusted for each type of thread. For a three-strand rope I count at least eight: for each bobbin the friction and the tightness of wrapping the thread, the rope tensioning device and the winding speed that has to be adjusted as that bobbin fills up. All these have to be re-adjusted each time you start a new cycle. Personally, I would think carefully about the maximum length of rope I need and arrange a batch-type rope-walk for that length. With a proper set-up, there are only two variables to control: the overall tension of the threads, if set-up continuously, and the number of twists for the threads. The tension you can control with a weight and you take note of the weight you used for a good rope. The number of twists you can count and record. Therefore, the settings are quite reproducible, something that I would find difficult to achieve for these continuous rope-making machines.

Don’t know why the manufacturer used these bulky thumbscrews. The parts are commercial hardware, perhaps for that. The bobbin will run on the screw thread which will not allow a smooth running. I would use a bolt with just a short thread on it. There should be a spring washer between the frame and the bobbin. Just pulling together the frame will not allow precision control, but jam the bobbin. The tightening nut either has to have a nylon insert, or there has to be a locking nut to not work lose.

Weren't the bolts for the feed bobbins meant to adjust the tension of the individual threads ? Uniform tension on all the threads is important for a smooth rope.

Boley (or Boley-Leinen) are considered prime makers, as are Levin. For some reason Boley prices are highter than the other (German) makes. Boley is one of the few makers, who are still in business, together with Bergeon (who are more of a distributor) and Levin. The Paulson lathes in the USA were actually made by Boley at a time when labour was cheaper in Germany than in the USA. If you want to know more on what was/is on the market Tony Griffiths in the UK has compiled a very comprehensive Web-site on small lathes: www.lathes.co.uk. If you want to learn more about these lathes, I would recommend to get hold of a copy of this book: CARLÉ, D. DE (1985, 4th edition): The Watchmakers and Model Engineer‘s Lathe – A User‘s Manual.- 193 p., London (Robert Hale). Makes you drool, but unfortunately virtually all of the suppliers have ceased to exist. And yes, 'druxey' is right, you should look for one with a cross-slide. Crosslides alone are somewhere around 250 to 500 €/£/US$ depending on the make, but I have people asking ridiculous prices on ebay these days. For a single collet I would pay between 10 and maximum 20 €, depending on the size and state. In a set they my come cheaper. Sherline sells acceptable 8 mm collets, but I still would rather go for antiques. However, their chucks are good value and I have several of them for 'rough' work. 'druxey' is also right about the collet-holding lever-tailstock, one should have one. The simple tailstocks are ok for supporting the work in a dead-centre, but whatever adapters people offer as after-market attachments, they are not so useful for drilling. It would be not too difficult to convert a simple tailstock into a lever-stock with a runner that has a socket for ER11-collets. If the tailstock is bored for 8 mm runners (and not for 7 mm as many are) than you will be able to find 8 mm diameter ER11-arbors on ebay. ER11-collets clamp down to 0.5 mm and hold drills much more securely than WW-collets.

Indeed. I am writing up my posts first in a word-processor document, which then is really a continuous narrative in which I am able to go back and check, what I have done.

Well, that is true up to a point. I have noticed that prices have gone up dramatically over the past 15 years or so in particular and would not be able to get anymore, what I bought 20 or 30 years ago. If my memory is correct (I am too lazy to pull out my records), I paid for my first quite complete set (a 6 mm Wolf, Jahn & Co. so-called D-bed or Geneva-style lathe) in 1988 around 1300 £ (I burnt a performance prime in my first job for that, at lot of money considering that my annual salary as a civil servant was 12k£ ). While initally this was a somewhat blue-eyed and innocent acquisition (I didn't know anything really about such lathes) with a practical purpose, it has become since a side-hobby in itself. Under today's circumstances one may need to think more carefully about the tasks one wants such a lathe for. For me the bigger (8 mm) lathe is my only 'real' lathe, but one could think of some model engineering lathe for the bigger work and use a watchmakers lathe with a limited kit only for the real small and delicate work. One of the main advantages of a well-kitted out watchmakers lathe is the flexibility and variety of work-holding. I am sorry, that I put the bug in the head of some of you and it may be unfair ...

Watched the whole presentation this evening. Very good and eloquent. Good to see another geologist at work here and putting the technological development into its socio-economic, cultural, resource geology and ecological context. Really appreciated it.

The silicone 'brushes' can be bought in most art-shops and through the usual auction Web-sites. They are meant to be used instead of palette-knives in painting with pastose acrylics and for sculpting in soft materials.

Sorry for that. You would have to register for the Forum. I wasn't sure, whether it would work for 'outsiders'.

By chance someone just posted a picture of such boat-cover made with silk-paper and white glue on our German forum:

Thanks for the friendly comments. As to sources for watchmakers lathes, there are several answers to that. Second hand ones: - by word of mouth and 'connections' - the usual auction sites - certain used tool traders There are very few makers these days and most would be out of reach for hobbyists: - Schaublin S.A. and Bergeon S.A. in Switzerland - Levin in the USA (but for these you really have to take a loan on your house) - there is one Chinese manufacturer, who makes lathes similar to the old ones

Silkspan, either in Northamerican understanding (silk paper) or European understanding (silk cloth), would have also been my suggestion. Military modeller use for tarpaulines in the likes also tissue paper: steam-iron out all embossments and stiffen it with acrylic or other varnish. Cut out the pattern and drape it over the boat. It may be better to use solvent-based varnish, as this can be softened for more compliant draping. Paint as required. These boat-covers had usually triangular flaps with eyelets sewn on, through which a rope would be roved to tie down the cover.

Maybe his workshop wasn't big enough ?

Speed is not so much the point, but regularity is important. For this you need a constant pull on the serving yarn and regular feed along the rope being served. This is on a model scale difficult to achieve by other means than a serving machine. Essentially, a serving machine is nothing else but two hooks that are driven synchronously so as not to impart a twist onto the rope being served. On of the hooks needs to be adjustable in position so that the rope can be tensioned. So, you need two identical sets of cog-wheels. Plastic ones are the cheapest, brass ones more posh and durable, but also far more expensive. Plastic ones can be found in model shops. There are also speciality suppliers, such as hpc-gears in the UK, who sell gears in brass, steel, nylon and delrin (https://www.hpcgears.com/). I gather cheapo plastic ones can be had for a couple of quid. Then you need some steel rod for the connection and the axles cum hook. That you get in DIY stores. You also a crank or something to turn one of the cog-wheels into a crank. Finally, you need some sort of base-board and two pieces of wood as brackets plus some screws to keep everything together. You can improve the machine by adding some self-lubracting bushings, rather than just drilling holes into the wood. They can be found on the Internet or in some model shops. For added sturdiness, I would probably make such machine much lower than the ones offered commercially. Not sure why they choose such spidery design. On the other hand, a high clearance under the rope being served allows you to use a self-travelling spool of yarn, as per the design by 'archojofo' here on the forum. If you had an old meccano set, you could fashion such machine also from those parts. Lego might work as well.

Not so difficult to build one oneself and it is always satisfying to make oneself the tools one needs. Some bits of wood, a steel rod as axle, four spur-wheels and some hardware - if you don't want for industrial production. There are some good examples here on MSW. There was even a thread on their construction a couple of years or so ago.

I think the knee-switches on home-sewing machines also contain a speed-control, as do many of the foot-switches. I used one for many years, but would not recommend it for most machines. It can be very tiring to hold the foot/knee at exactly the same position in order to keep a steady speed when drilling, milling or turning. I prefer a separate speed-control that allows me to pre-set the rpms.

Boat-davits – Part 2 The davits lock into the mounting plate on deck and are fixed to the rail of the bulwark with a bracket. This arrangement is entirely conjectural, as there is no suitable photographic evidence. The mounting plate is a simple piece of turned and drilled brass. The brackets started as thin discs with a slightly raised hub in the centre. From these discs three sides were milled off on the micro-mill to arrive at a rectangular plate with the raised hub at one end. Nothing spectacular either. The boat tackle is belayed on a clamp that is fastened to the davit. The clamps were milled from a piece of 3 mm x 3 mm square brass rod (because I didn’t have 2 mm x 2 mm in stock ...). They are so tiny, that it would have been difficult to take pictures of the process. Again this was really only made possible now that I have the stereo-microscope in working order. First, the profile of the clamps was milled along the whole length of the brass, while it was clamped horizontally in my micro-vice. Next the piece was mounted upside down and a groove milled to fit onto the davit. The vice then was clamped vertically in the dividing head of the mill and the clamps sawn off. The clamps and the bracket were soldered to the davit. For some reason I always struggle with soldering such parts whatever materials and tools I am using ... wanted to use soldering paste, but somehow mine didn’t work. In the end traditional solder did the job. The eye-bolts were bent from tinned 0.15 mm copper wire. Tinned wire was used to make soldering it into the pre-drilled holes. First I formed the eyes around the shaft of a 0.25 mm drill, but then found that I can form them just with a pair of fine tweezers equally well. The wire ends were cut off flush with a pair of cutting tweezers, but a scalpel on a glass plate would have worked also. Using a Novotex-clamp to hold the davits for re-drilling Soldering the eye-bolt didn’t quite work out first for the same reasons. I then tried to cement them in using shellac, but the joint wasn’t strong enough (I don’t have CA around and don’t like it anyway). It took a while until I developed the right strategy. Also, I didn’t dare to drill 0.2 mm right through the spheres, but with control under the binocular it can be safely done. It turned out that I had to re-drill various holes, because they became filled with solder. Holding the davits for re-drilling caused some head-scratching at first, but then I remembered that I had made clamps from fibre-reinforced bakelite (Novotex) for the third hand and took one into a 4 mm collet in the dividing head. This proved to be stiff holding arrangement and watching the drilling under the binocular, allowed the check for any dangerous deflection of the drill. The finished boat-davits So on the bottom line, the following strategy would have been best (and was put into practice for some of the davits): - drill the axial hole first on the lathe, bend the davit and the solder the eye into it; - then cross-drill horizontally; - insert an eye-bolt with a long leg and form the other eye with a pair of tweezers, so that both eyes are pulled tightly against the davit; - solder the pair of eyes; - cross-drill the vertical hole for the eye-bolt into which the boat-tackle will hook. - insert an eye-bolt with a long leg and squeeze the leg flat, so that it cannot slip out. - solder this last eye. When the soldering is done fast and the other eye are not touched by accident in the process they will stay put. Boat-davits temporarily installed To be continued ...

Looking at the hull, as it emerges, I slowly begin to understand the difficulties in planking it. The bottom is rather flat, particularly aft, which means that there is a sharp turn into the planked deadwood. I have seen other such hull forms, where the deadwood was not actually planked. I should think that from now on the planking should become somewhat easier to fit.

I am running all of my machines from foot-switches - they have momentary switches, not the ones that switch on and off with a 'click'. Lifting the foot immediately stops the electricity. I set one in front of the transformer from which I run all the low-voltage equipment.

Thanks to all. The tailstock-mounted steady, Keith, is a bit of a compromise, as it is difficult to put a travelling steady onto a watchmakers lathe. On them it's the top-slide that does the x-movement and a steady as whole would move with every movement in the y-axis. For work in confined spaces I made myself another steady that fits into the same tailstock holder: I am not entirely happy with the arrangement, as it is not so easy to precisely set the finger. One day I may make a micrometer feed mechanism.

Just realised, that I had made the same comment already earlier on. Apologies for the repetition ...

This is a thought that occurred to me as well earlier on, when you had problem fitting the garboard to the rabbet. I believe in real life boatbuilders let the planks cool down and dry before the final fitting, leaving them a tad longer and wider for the purpose.

Polyurethane varnish diluted, so that you can wipe it on with a rag. Very popular across the pond, but less so in Europe. I guess people here prefer either nitrocellulose varnish or shellac solution. When you say mast-colour, do you mean the colour of a mast after a certain treatment or the colour of paint that was/is used to give (metal) masts a sort of yellow colour ? I am asking this because I have the suspicion that you are looking for the right colour for your Imperial German yacht, right ? This paint was some sort of ochre. The problem is that ochre can have a wide range of colours, from almost blueish red to a pale yellow, depending on where it comes from and how it is processed. I did some research for the Imperial German Navy, but did not get very far. The German Navy refers to it as 'Mastenfarbe', i.e. mast-colour, but there were no standards at the time. I made some enquiries at the Chatham Dockyard Museum as to what they used during the restoration of HMS GANNET, which has the typical later 19th century yellow masts, but due to COVID, I didn't get very far. Photographs can be misleading, but according to the picture I took some years ago, this ochre has a light pinkish tint. Otherwise, masts treated with oil or pine tar will look somewhere between your samples 1 and 2, depending on the type of wood. I gather, if you used unbleached shellac, you would get about the right colour, which is slightly orangy. After applying the shellac, you can rub it down lightly with a humid cloth and some pumice dust or with very fine steel wool until you have the desired depth of colour. Rebuff to a light sheen with a cotton cloth or felt buffing wheel. This surface treatment doesn't add a visible layer of varnish, but gives a depth of colour.

Well, I used to run 20 turns around the shaft of a drill, not too tight, not too loose and then measured the distance. Divided by 20 gives you the thread diametre. We had the discussion recently in another thread: using the bulk density of the material, say polyester, the den or tex and a bit of geometry, one can also calculate the diameter. For instance, vor Veevus 16/0 fly-tying thread, which has 50 den, I calculated 0.04 mm and a colleague here measured 0.038 mm - so a pretty good match.

In fact, various details changed, for instance in later models (or only vor the 2CV6, i.e. the one with the bigger engine) the headlights became square. Also the metal radiator grille, which was chromed, was changed into light-grey plastic. I vaguely remember that other parts that were chromed were changed into plastic. There were also different colours of the roof. Mine was originally the colour of the car, but the replacement I got after it had been vandalised (someone thought it funny to cut it open ...) was grey. In addition, over the years they produced various 'special editions', e.g. the one with a two-colour paintwork in bordeaux/black was called 'Charleston'. These also had chromed wheel-cups on two-cloured rims. I don't remember the colour of the wheel-nuts (the paint seemed to wear off), but the the special washers were light grey as the wheels usually were.