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wefalck

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Everything posted by wefalck

  1. This problem has been nagging me for decades actually. So mentally at least, I probably have been through most of the ideas: - making a set of dies to shape a block from soldering tin around a wire - inspired by the lead seals you see on electricity meters and the like; could work for larger sizes, but it would be difficult to pull out tiny wires, even when you use tungsten or NiCr. - same idea but using the dies to shape a ball of two-part expoxy (Milliput or similar); same problem with releasing the wire when set or distorting the block, when pulling it out while the epoxy is still soft. - casting in some resin using silicone moulds with wires embedded to keep the hole open; again releasing the wire is the problem. The last two methods would allow to imbed internal strops relatively easily. Somehow, I came to the conclusion, that some rough-machining with good old hand-work in some reasonably hard and dense material (I prefer bakelite) is the solution - unless ... - I have tried to entice a colleague for some time now to design some blocks and print them in his UV-curing resin 3D printer, but he hasn't got around to do it yet. Even if the printing doesn't keep the space above the sheave completely open, re-drilling it is much less work. All the grooves for the rope strops etc. would be formed on already, of course. Making rope-stropped blocks is much less of a problem than internally stropped ones. However, one could 3D-print them, then add the wire-strops as per Wingrove's method and fill/seal the grooves with a tiny blob of UV-curing cement.
  2. Been down that road, but it turned out to be a cul-de-sac ... when you are working on 1 to 1.5 mm long blocks, this means that the strop is 1/10 the diameter, i.e. 0.1 mm. If you flatten that not much of substance is left ...
  3. The idea is that the solder fills any gab between the wire and the slot, so silver soldering may not be ideal and one may actually burn away thin wires …
  4. Thanks, Roger, that gives me indeed some more ideas 👍 Internally stropped blocks are particularly difficult to make. I think I would mount the rod excentrically in the lathe, as the sheave sits a bit closer to the bottom end of the block. However, grinding such form-tools is probably the most difficult part. The key idea probably is to wrap the wire around in a groove, solder it in and then file the cheeks of the blocks flat. Could be perhaps also done with (super)glueing, using some highly-viscous CA. As I said, gives ideas.
  5. I love this filigree and intricate appearance of such small-scale models. Good job !
  6. A tank is a must for a useful compressor - otherwise you will have constant pressure fluctuations.
  7. As Roger said, when contemplating on of these air-erasers, one has to carefully consider the modelling environment. They were developed originally for professional draughtspeople, so a sandblasting-booth is not necessarily needed, but the resulting dust would not be welcome in a domestic environment. There are, however, also shoebox-sized sandblasting boxes that are sold together with them. Railway modellers seem to use them quite frequently to prepare their etched-brass kits for painting. When buying a compressor to use in a domestic environment, particularly in an appartment, the noise and vibration generated can also be an issue. Cheap models may be a problem in this context. Also, an air-eraser needs more pressure to be effective, than an air-brush.
  8. That's kind off-topic, but during the first colonoscopy I had (in Austria they do without general anaesthetics, unlike here in France), the doctor asked me, whether I would care to look on the screen at what he was doing - provided me with completely new insights into myself
  9. That looks all like rather complicated pieces of hardware - I hate these parts that stick out at oblique angles that can only be determined on the object itself - difficult enough in full-size and a challenge on a model. Well done !
  10. As an add-on: delicate parts often cannot be treated mechanically and the application of acetone might dissolve glued joints in composite parts. Brush-painting using acrylics typically is not successful, put building up thin layers of spray-paint works without de-oxidising etc.
  11. The subject has been covered indeed in several threads in recent times. In a nutshell: brass forms a sort of 'greasy' oxide layer with time to which paint, incl. primer, does not adhere very well. Brass should be brightened before painting. This can be done mechanically, e.g. by rubbing it with fine steel wool, using rubber-bonded fine abrasive wheels, etc. Pickling is also a solution, as discussed in a quite recent thread on pickling material, the availability will depend on your region. In any case, I would wipe the pieces with acetone before painting to remove any possible traces of grease and not touch them again with bare fingers.
  12. I am rather surprised to read about double-planking for a kit of an open boat. The rough first layer of planking would be very visible on the inside, doesn't make much sense.
  13. Good to hear. Take your time and don't give in to forum pressures I hardly dare to say that we are just back from tasting Italian food in Italy ... spent a few days in Venice. Took also the opportunity to visit again Gilberto Penzo (http://www.veniceboats.com) to get a copy of his latest book: http://www.veniceboats.com/libro-Il-trabaccolo.htm.
  14. This is indeed a dilemma that makes me shy away from kits, as attractive as they may be: I am afraid that I would throw away half of the parts ...
  15. ... however, in fair weather, they were left open to aerate
  16. On the topic of replacement parts: I was actually wondering, whether it would not be better to replace parts that would have had machined surfaces on the real thing with machined parts - thinking of axles, piston rods, bearings, bushings, the crankshaft parts etc. I would have probably done that, as the machined surface is so much more precise than the cast surface. Oh yes: the model is coming on very nicely !
  17. Actually, I have seen quite a number of models with hammocks in their boxes/netting and people discussing ways to make them, from rolled toilet-paper to epoxy putty ... The hammocks were tightly packed against each other - storage space was precious and not the whole crew's hammocks could normally be stored that way. Here is an image of a contemporary model of the French BELLE POULE (1834) in the Musée de la Marine in Paris, as fitted out to retrieve the remains of Napoleon I:
  18. The 1847 edition is available on-line, the 1860 one not, as far as I know: https://archive.org/details/elementssailmak00kippgoog Didn't have time to check on the issue ...
  19. Pat, just a couple of comments on your questions in the last two posts: - you wouldn't need to worry about showing individual mast-wedges. They would normally be hidden under a painted/tarred sail-cloth cover that is nailed down to the deck and to the mast. The upper edge may also be fastened to the mast by winding a thin rope around it, that would also be painted over. - the eyelets/cringles for the mast hoops are usually set into the seams between two sail-cloths. Sometimes there is an additional in the middle of the cloth - this depends on the angle with with the cloths run against the mast and, hence, on the effective distance between the eyelets. The sail-cloths would normally run parallel to the after edge of the sail, so the angle at which the cloths intersect the mast depends on the angle of the after edge of the sail. - the hoops are normally strips of flexible wood that are thinned out at the end to overlap. The overlapping ends are 'sewn' together. At this point the hoops would be lashed to the eyelets/cringles of the sail.
  20. I don't know for the RN boats, but he German ones were originally painted black and later in the War in dark grey. I would assume that the decks assume after a short while a dark grey colour, similar to older tarmac, due to weather and wear.
  21. Yes, I have had such a slide since the early 1970s for my SLR (Novoflex, together with the bellows and all that gear), but getting the iPhone focus to stay at the place where you want it to is not so easy, as it tends to adjust itself all the time ...
  22. One problem I have with close-ups and 'macros' using the iPhone is that it is very difficult to target the focal plane - there no really good manual focus.
  23. Cutting thin(!) copper sheet with a steel ruler and a cutter on a cutting-mat should not be really a problem. Don't try to cut through in one go, but in several passes. A pair of old(!) scissors should also work. Straighten out the strips/plates by rubbing them softly with a cork on the cutting-mat. You may also need to sand the edges slightly with very fine wet-and-dry paper to remove burrs. If you have a table-saw, you can also stick the copper sheet with a glue stick to some thin MDF or plywood and then cut the strips with a fine-toothed saw-blade.
  24. I am virtually always seated when working, but then I have only miniature machines. When considering the height of benches for machines, one has to consider from which angle you would be mostly looking at the work, so that one can watch both, the surface worked on as well as the cutting tool (this being a lathe tool, saw blade, abrasive disc, etc.). When working seated on details, one may want to consider also arm-rests as e.g. jewellers use in order to relieve your back from bringing your hands up to eye-level for prolonged periods of time.
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