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bartley

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  1. Bruce, Those bands on the ends of the draw bar would have been heat shrunk on I presume. Real blacksmith stuff that! John
  2. Steering Mechanism and Haul Bar This is quite a complex piece of woodwork and stars with four laser cut parts 5 mm deep, the curved steering bar, the haul bar and the steering struts: The Haul Bar is cut from 5 X 5 mm stock walnut and the end fashioned to a "knob" The parts are assembled in such a way that the haul bar moves freely between them: Ironwork was then added. In fact these clamps are actually brass, of course, but I don't think there would be much brass on these coaches so I chose to blacken them and then app;y a little weathering to make them look like iron. The side clamps are showm prode of the haul bar but I chose to inset them a litle The sqaew clamps were fashioned from 4mm brass strip and then the ends were silver soldered together: The final appearance of the unit is shown below Wheel Axels The real axel is made from 9 X 9 mm walnut stock and 5mm diameter holes need to be bored in the ends to take the stub axels The length was too long to fit under my mini drill press so the firs method I chose was to use my wood lathe. I have a 4 jaw chuck but it is not self centering and is difficult to set up. I thought I had it correct but with the length of the axel there was some precession and the hole hole turned out slightly conical. For the second axel I mounted my Dremel horizontally, chocked up the alxel and pushed it onto the drill. Surprisingly this made a near perfect perpendicular hole! In each case I stated at 1mm, then progressed in mm steps to 4mm, Here is the front axel: John
  3. Hi Bruce, Early days yet so it is a bit hard to comment on the quality of the kit. I think that the cabin will be the real test. However, so far it looks OK. The hubs are boxwood. The laser cut parts are walnut/boxwood and seem quite accurate. There is quite a lot of "scratch" work such as fabricating the spokes from dowel. This makes it a bit less like "painting by numbers" John
  4. The Main Chassis This consists of three long beams connected to two suspension stabilizers. You will note that these both show "clefts" where presumably narrow planks where joined to make a wider board. These were produced using a mill and a 0.4 mm Kyocera end mill. After painting the two oposing edges, the beams were connected to the suspension stabilizers ensuring that everthing was at right angles: The final result looks like this John
  5. Thanks for the info, Bruce. It sounds like I will need to be careful with an expert watching on! John
  6. Thanks for your interest Bruce, Yes, they are butt-jointed here on the model but on that historical wheel that I showed they are let in at the felloe end as well. In fact, on the model some of the but joints gave way and needed attention so it would not have been a viable system on a "real" wheel. At the Toowoomba museum in Queensland one can observe a wheelwright in action making a wagon wheel. First, all twelve spokes are driven into square holes in the hub. Then "pegs" are cut on the end of each spoke. Eight segments of the rim are made with holes bored at the correct distance. These are hammered onto the spokes. And it all locks together, NO GLUE!! John
  7. Thanks Mark, There's a few finicky bits to do on those wheels yet but I am moving on for the moment. John
  8. As an interlude from ship building I decided to build a Concord Stagecoach. These were originally made by Abbot Downing in Concord, New Hampshire were common through the American wet in the 1860’s but were also operated in Australia and New Zealand by Cobb & Co as mail coaches and also transport to the goldfields. This is a kit by Artesania Latina but will be bashed to achieve a more “Australian” look. This initially seemed to be a quick project but has turned out to be more complex than I first thought. The first task is to construct the wheels. Here is a wheel from about 1900 on display at my local timber merchant. It is probably from a bullock cart not a coach, but it gives an indiction of the mrthod of construction. These wheels have twelve spokes arranged around a rim, which in this case is constructed from four segments. In order to get these as perfectly round as possible I drew a circle of the appropriate diameter and then used the jig shown to make the two halves of the rim. The two halves were then glued together: The spokes are made from 4mm sapelly rod, which were sanded flat on two opposing sides to achieve a final thickness of 3 mm. The hub supplied was sanded smooth and the twelve holes bored at 30 0 to each other A simple jig was constructed to ensure that the spokes were evenly spaced. This consisting of a sheet of ply with a hole in the center to take the hub. the positions of the spokes were marked at the correct angles. Four spokes at rigt angles were added first. Then the rest added in a systematic manner The rims and the front and rearof the spokes were painted with Vallejo Model Colour #79.858. The inside edges of the spokes were left un-painted. And here are the four wheels completed:
  9. Looks great, Paul. The treenailing, the dullish red and other features make it look "authentic". some I have seen from very accomplished modelers look a bit "plastic" to my eye. John
  10. An interesting aside to the obviously brilliant work of Grinling Gibbons is the fact that his signature was a pea pod. If the pod was open he had been paid for the work . If it was closed had had received no payment. John
  11. Post 65: Construction of the Yards. Work on Cheerful has been slow of late since we have only just returned from a six week holiday to the north of our state. And now we are embarked on some major renovations. Nevertheless, I have found time though to start work on the yards, The yards were turned on my home-made lathe. It may be of interest to know that we did originally consider the Proxxon DB 250 lathe which we were able to assess at our local supplier. However, we felt there were some limitations: 1. There was no provision for a central support. 2. The speed control seems to be a simple rheostat so the torque at high speed was very poor. 3. The bed length is quite short and the much vaunted hollow headstock was, we felt, limited because if the work-piece was extended more than a few centimeters into the headstock considerable whipping occurred even on round dowels. 4. The tool rest is very short and the adjusting handles obstucted the tools. I felt I could address some of these issues andconstruct a superior tool using a simple power drill as shown here. I use a switch mode power supply to control the drill speed and find that this provides quite uniform torque. A colleague has adapted my design by incorporating a belt driven motor and obtains even better performance. A feature of this design is that the length of the work piece is not an issue and the tail-stock (which consists of a roller blade bearing) is hollow and can be clamped in any position. The original idea was to extend longer work-pieces through the tail-stock. I now find that using a central bearing obviates the need to do this and I now only extend the work through the tail-piece in order to turn small diameter ends of spars and masts. The present task is a case in point. Since the central region of the yards is octagonal the central bearing insert was made octagonal using the FF 230 mill. After turning the yard: the stop cleats were fashioned from 1/8" sheet After painting black the stirrups and footropes need to be installed. In his monograph Chuck suggests the stirrups should hang below the yard by 11 /16 “ This equates to17.5 mm. However, the plans show a much shallower distance than this. I spoke to Chuck about this and he said that he obtained conflicting advice on this issue and on the model he “split the difference”. David Antscherl in his book suggests that the footropes should be 3’ below the yard and that this can be achieved with stirrups of 2’ 9” This equates to 17.4 mm at the model scale. This seems excessive since my waist is only about 3' from my feet! In the end I elected to make my stirrups hang 12.5 mm below the yard. The Stirrups are made from 0,63 mm rope by first forming a loop by using a needle to draw the end through the main strand then tightening this around a 0.8 mm drill bit . The loop was sealed with shellac and a small seizing added These are then suspended from the aft end of the yard using a copper wire to keep them at the same length Finally the horse was threaded through the lools and seized to the yard as indicated in the plans.
  12. Post 64: Topmast Stay Chuck points out that these were not always rigged but he chooses to rig one himself and I propose to do the same. I will also rig the topmast back stays as it would seem to me that the physics demands neither or both to balance the forces. Also if the topsail is rigged then most of the time the pressure would drive the mast forward and demand back stays be fitted even if te leeward one is slackened in practice. So the topmast stay starts with a seizing to the end of the bowsprit: this tip of the bowsprit is a pretty busy region. You may recall that four blocks were fitted here much earlier: and there are also two hooks for the bowsprit guys and now this new seizing. (Incidentally the ropes attached to the 3/16 single blocks will form the braces for the main yard. They have been sitting there fro a couple of months!) The stay then travels through a block seized to the topmast: Then down to a tackle block here: This tackle passes through a block hooked to the base of the mast and is finally cleated at the front of the mast, as shown by the red arrows here: The main yard will be next but there is quite a bit of work to do on that. John
  13. Thanks for your comments on the weathering, Glenn. I take your point that the effect here is much more subtle than the applications that I am used to. Even so with the cannons, I weathered hem off the ship and I had to "handle" them later to attach them to the carriages and fit breaching ropes. Not handled with fingers of course I have som3 foam tipped jewelers tweezers. Nevertheless I did give them a spray of Dulcoat. I couldn't see any difference in the appearance before and after. but as you say in cases were the fitting is already installed coating is not possible but thenit wont be subjected to further manipulation. Thanks for the explanation of your approach. John
  14. Great Build Glenn! I would be interested to know if you needed to protect your weathering. In my previous modeling life involving vintage rolling stock and vintage aircraft we made extensive use of washes and weathering powders to simulate rust. We found that we needed to use a varnish such as Dulcoat to protect the weathering powder otherwise later handling would abrade the weathering. Did you feel you need to do this? Unfortunately these models were made for the museum and I am unable to reproduce photographs of these models. John
  15. Yes Allan, I use shellac a lot as well. But this pH scale is not easy to get your head around. It is common to think that the difference between pH 6 and pH 5 is "not much - its only 1 in 5 or 20 %" but the scale is logarithmic. This means that when we go from pH 6 to 5 the acid concentration goes up by a factor of 10 and if we go to 4 i tgoes up by a factor of 100. It also means that going from6 to 6.2, the acid concentration doubles! The message is that a small difference is significant. It is also not so easy to measure particularly close to neutrality and for things that are not soluble in water, so some quoted figures may be questionable. Confusing, I know but the closer to neutrality the better. John
  16. Post 63: Topmast shrouds Ratlines are now complete and all knots sealed with shellac. The topmast shrouds are run in pairs from the top mast They then run down though the cross trees In preparation for the tackle to secure these a 1/4" block needs to be seized to each shroud and another to a hook finally the tackle is then rigged to eyebolts on the chain plates Next up the topmast fore stay. Chuck points out that these were not always rigged but it seems to me that if there were a sail rigged on the topmast yard then some support of the topmast itself would be required. John
  17. For what its worth I have done a quick chemical analysis of Super Phatic. For those in the know I used Attenuated Total Reflectance Infrared Spectroscopy (like most exclusive clubs, we scientists invent this special language to keep out the rifraf!). This technique is quick (ten minutes). It cannot usually unequivocally identify a substance but can eliminate some possibilities. So, It is not CA and it is not PVA. It looks like an acrylic modified with polystyrene. There are other techniques which could confirm this but not really worth spending my time on really. John
  18. Make your own is, in my opinion, the answer to many of the issues raised. To a certain extent you can control the appearance to suit. Gutermann Mara comes in such a range of colours that dyeing is unnecessary, and, as I pointed out in my Cheerful build, you have matching seizing thread in sizes from 0.1 to 0.3 mm. John
  19. Seizing revisited My Cheerful has been on hold for a while since we have just taken our annual holiday. My other hobbies have also interfered with my shipbuilding. In the past I have used various threads (16/0 fly tying line, 50 wt sewing thread, etc). However, since I am now making my own rope it suddenly dawned on me that it makes more sense to use the Mara thread I use. It obviously matches perfectly and comes in a variety of sizes. For example: Mara 220 has a diameter of 0.109 mm Mara 150 has a diameter of 0.135 mm Mara 120 has a diameter of 0.14 mm Mara 100 has a diameter of 0.17 mm Mara 70 has a diameter of 0.19 mm Mara 30 has a diameter of 0.30 mm For comparison: Gutermann C Ne 50 Cotton has a diameter of 0.128 mm Here is an example of its use in seizing: 16/0 fltying line is still thinner. The diameter is hard to measure accurately. The old technique of wrapping 10 or 20 turns around a dowel is difficult with any thing less than about 0.3 mm in diameter. It is quoted in one source at around 0.05 mm. although my calculations based on the Denier given by the manufacturer produces a value of 0.105. Even so for small rope I might keep using it. John
  20. Yes, Glenn, I had a conversation with Chuck about this and in the end it turned out to be to do with my scan of the plans. I don't know why. It has never happened before or since! Anyway my grid turned out to be exactly the same as the plans anyway so I went with that. By the way your rope coil method is very elegant. Interestingly enough I had that method of Peta_V in my files but had forgotten about it. The idea of using two pegs of different sizes is a good one . This is how I modified Tom Laura's. method in the end rather than use pins as he does but I still had to use two pins at the top to get the loop to work. John
  21. Brass is an alloy of copper and zinc while bronze is an alloy of copper and tin and sometimes other metals. So, both will react with pickling compound but it is designed to remove oxide coating. However, as Mark says the contaminant may simply be wax and if so a bit of heat is worth a try before going with a chemical treatment.
  22. Brass is an alloy anyway so "alloy of brass" is a kind of funny term. Anyway if it is brass, you might try a pickling compound like Sparex but be careful it does etch the surface if left to long. Maybe try brushing it on and then stopping the reaction with bicarbonate of soda. John
  23. Hi Glenn, Looking good! Your faking down (rope coils) looks good. How did youdecide to do these in the end? I used a modification of Tom Lauria's method but it is a lot of fuss and a smpler method would be good. John
  24. Post 62: Ratting Down For some this is a tedious job but there are only a few to do on this ship. The first issue is that there is some kind of perspective distortion on the plans which results in the spacing of the ratlines decreasing towards the top. I spoke to Chuck about this and he agrees that the spacing should be the same all the way to the top. It is a ladder after all. Therefore I drew my own grid in Illustrator with a spacing of 12inches which corresponds to 6.32 mm at this scale. In order to avoid the "hourglass" effect I did two things. First I camped the shroud to the card grid neat where I was tying. I discovered this technique somewhere on this site but I can't remember where to give proper credit for the idea. The second thing I did was to first tie at an interval of twelve then six then three. As we know on the real ship eye slices were used on the outer shrouds. Ed Tosti's book on Young America illustrates this well but it is difficult to do at this scale. The essence of this technique is that the line on the outer shrouds travels inward towards the middle shrouds. I simulate this by using a cow hitch on the outer shrouds and clove hitches on the inner ones. The problem with a cow hitch Both exit stands need to be held under tension. If only one is under tension the knot slips. Indeed this is the purpose of the knot as I well know from using it as a leg rope on cows art milking time. I digress. So, on can make it more stable either by following it wit a half hitch or by passing the free end back through the coils, This is what I have done here. The port side is nearly complete. Only the starbord to go John
  25. I agree wholeheartedly, Bob. I have worked in the chemical industry and so know a little about these chemicals. All acrylics are made small monomers which are derivatives of acrylic acid. However, as members of the general public we do not meet these because we only see the polymers (in fabrics, paints, plexiglass etc). It is generally only the workers in the industry who are exposed to these acrylate monomers. However, CA polymerises by contact with moisture in the air and the bottle actuually contains the acrylate monomer. These acrylate monomers are highly volatile, have an unpleasant odour, are lachrymatory (make us cry) and about 5 % of the population have an allergic reaction to them. Others develop an allergy after a period of exposure. I agree avoid CA as much as possible. John
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