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    Thames barge Champion class model building report
    12 Posts ยท 3 Followers ยท 101 Photos ยท 52 Likes
    Began 1 month ago by
    Midshipman
    Czech Republic
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    Latest Post 19 days ago by
    Midshipman
    Czech Republic
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    ๐Ÿ“ part13
    19 days ago by ๐Ÿ‡จ๐Ÿ‡ฟ tomarack ( Midshipman)
    โœง 16 Views ยท 4 Likes ยท 1 Comment
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    When I finished the model, I was very excited and immediately took it to the lake in the park to test it out.
    I didn't even have a fin with a 3 kg lead bomb at that time.
    The model looked very good on the water, but it didn't want to respond to the rudder at all when it was powered only by sails. Fortunately... I have an auxiliary motor in the model, so it was no problem getting it to shore.
    I finished the fin keel and thought it would be fine - but it wasn't. In a short time, a friend took me to a regatta at the Vรฝrovice dam near Znojmo. After arriving, I completed the model and the next morning the race in the free category started.
    The model swam to the start, and instead of starting to race, it just drifted sideways away from the start. First run - 0 .
    Now all my construction mistakes were added up. I had to come up with something quickly. The easiest thing seemed to me to use a large outer jib sail on the bow instead of the original small one. After this modification, my Capricorn finally went out on the race course - even though it had no chance against the others. During the last run, the battery failed, and I only managed to reach the shore from the starting point. This time it was a bitter end...
    At home I put the model on the shelf and devoted myself to building other models. I only occasionally took the model to the water.
    Gradually, however, I adjusted the rigging of the front sails. I left only the fore sail and only one - the big one - jib sail. Because there was little space to pull the sails when tacking, I made a new bowsprit 50 cm long - 10 cm longer than the original one. The model now behaves as expected.
    I wondered why the model didn't want to sail under sails the first time. The answer was probably the simplest...my mistake when building the model, when I placed the fin right behind the main mast. According to experienced modelers
    it should have been at least 3" ( 7.5 cm). The center of gravity of the sails was thus above the center of gravity of the side surface, instead of being a little in front of it.
    There was probably another option - to lower the mizzen sail, but that didn't occur to me at the time.
    As an attachment, I am attaching photos of the model on the water...how it has progressed over the years.
    If anyone has any questions, I'd be happy to answer them.

    ๐Ÿ’ฌ Re: part13
    19 days ago by ๐Ÿ‡ฌ๐Ÿ‡ง luckyduck ( Sub-Lieutenant)
    โœง 15 Views ยท 2 Likes
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    A very beautiful model Tom - but even the beautiful models don't always behave themselves!!๐Ÿคฃ
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    ๐Ÿ“ part 12
    29 days ago by ๐Ÿ‡จ๐Ÿ‡ฟ tomarack ( Midshipman)
    โœง 28 Views ยท 7 Likes
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    Anchor winch barrel I made from wood and gear wheels from the alarm clock.
    To ensure its functionality (which was offered here), so bearings for shaft I made from brass tubes ร˜ 5/4 mm.
    For the pinions, I made a "housing" of brass plate thickness 0.4 mm, soldered to the copper strip 5 x1 x 60 mm with required spacing .This strip it is glued and riveted to the back of the wooden winch knees on the bow.
    When compiling the winch, I glued the reel in wrong way , so winch thus not functional. On the front of stem post of the model, I'm stuck copper stem band (with a cross-section 5 x 0.8 mm) and riveted it using short pins. This band is at the upper end provided with an eye for main mast forestay.
    On the back of the stern post, I stuck the rudder hinges, and according to them, I placed and stuck the hinges on the rudder. and next.
    The anchor is made from copper wire 3 mm dia. Painted black.
    Main mast
    The main mast is made of aluminum tubes of ร˜14/12/10 mm inserted into each other and glued together, with a total length of 57 cm. The lower part of the mast was glued into a foot made of hardwood. Jackstay - auxiliary "stay" used for attaching the front edge of the main sail is made of brass wire ร˜ 1 mm, soldered to the heads of M2 screws, screwed and glued into the tubes from the back of the mast.

    Main topmast
    The topmast is made of a ร˜8 - ร˜6 mm laminate GRP cone from fishing rod with a length of 59 cm and reinforced with a ร˜ 4 mm carbon tube with a length of 63 cm, which passes through the entire length of the cone and at the same time fulfills the function of extending (the top) of the topmast. It is glued to the cone with PUR glue.

    Crosstree
    I simplified the crosstree a bit, I didn't have suitable brass profiles, so I made the arms from an old umbrella, so they are foldable, like the original.

    Mizzen mast
    it is sanded from a 10x10 spruce beam with a length of 28 / 30 cm according to the drawing.
    The tabernacle of the mizzen mast, I cut out, bent and welded from copper sheet thickness. 0.5 mm. I drilled a ร˜ 3.5 mm hole in it for the axis of the rudder, and two ร˜ 3 mm holes in the feet for attachment to the superstructure. Painted green.

    Mainsail sprit,(spreet )
    The sprit is made from a beech log with a diameter of 8 mm and a length of 75 cm, ground towards the ends into a slight cone.

    Mizzen sprit
    it is made from a spruce log with a diameter of 4 mm and a length of 40 cm

    The boom of the sail on the back mast
    it is made of a spruce log with a diameter of 4 mm and a distance of 27 cm

    Bowsprit
    The bowsprit is ground from a 10x10 mm spruce beam, 40 cm long. This profile remained on the foot for a length of about 4 cm and was then ground above the foot into a round to ร˜ 9 mm and further as a cone to ร˜ 6 mm at the tip.
    In the main cargo area there is a winch with runneer on rail for main sheet, a lever servo for vangs, auxiliary motor, battery, sound module and relay board, ESC and 8-channel receiver.

    I made a bar with a spring in an aluminum holder from U profiles. I fixed there also a runner on a steel rod, from which the sheets will lead on deck to the sail. I set the winch using a servo tester.. it now seems to me to be the most important thing for setting the servos in the model, which otherwise I would have to do with the RC equipment turned on and with the possibility of damaging the servo.
    Next I made the base of the sheet winch and base plates for the mizzen servos.
    To control the main sheet I bought a 6 turn servo winch with a drum and attached this to the base rail. I stretched the auxiliary loop between two pulleys, one fixed, the other a removable plate for fixing the servo for the rudder
    I planned to use additional zwo servos to control the mizzen sail as per Ivor Bittle.
    In the end, however, I had to choose a simpler design without the aforementioned servos due to space, by attaching the mizzen sheets directly to the rudder , as far back as possible, as practiced by most English modellers.

    Electrical equipment - battery, ESC
    I chose a 12V/2.3 Ah gel battery as the battery. I chose this type, among other things, also because it creates a functional load for me. I placed it in the centerline of the boat just behind the fin box. It is built vertically, but I had to lower it as low as possible to guide the reins. For this reason, it was necessary to partially cut off a piece from the height of the keel, fortunately the strength of the structure did not suffer. The 12V voltage distributions to the individual electrical units are controlled by manual switches located on the distribution board (ESC (motor), lighting, sound module, sound module relay, 5V auxiliary power supply for the mini camera). For more convenient switching off of the equipment in the model on the water, the main switch is located behind the companionway hatch on the rear superstructure. Starting and stopping the engine is already done using RC equipment. The receiver of the Rc apparatus and the speaker of the sound module are fixed from below on the cover of the main hold. The electronic controller (ESC) and the relay panel of the engine are located on the side wall of the main cargo compartment.
    A servo for controlling the jib sheets is located in the front cargo area. But how it will work is still a big unknown for me -

    Installation of auxiliary engine.
    During construction, I gathered additional experience from building barge models published on the Internet. I finally decided to add a 12V - 0.35/1.5A electric engine to the model. I can also use the battery capacity without further modifications. I measured everything so that a ร˜ 40 mm ship screw could be used, and because of the engine it was not necessary to cut the bulkheads. A similar solution was also applied to large barges, the engine was usually on the left side of the hull.
    I drilled a hole in the hull, seated the shaft bushing and sealed with Mamut silicone adhesive. I glued the engine bed together from plywood and a wooden wedge to adjust the engine pitch. I couldn't buy the cardan coupling on time, so instead I successfully used a thick-walled PE tube ร˜10/ร˜4 mm. The engine is fixed to the bed in the shape of a wedge with metal clamps, the bed with the engine to the bottom of the boat with Velcro. The engine is controlled using the MD18DCRS electronic controller (ESC) in the basic setting. . The ESC and sound module (diesel engine) are controlled by one channel of the receiver and wired so that the ESC is in one branch and the sound module in the other branch of the Y cable.

    Rig and rigging
    I made the shrouds from black waxed cotton string with a diameter of 1mm, backstays from wound cords from parachute cords with a diameter of 0.8mm. I also used these cords for some parts of the moving rigging, as well as for boltropes.
    I already had to wind the thinner "ropes" for the sheets and next ropes on the ropewalk (last two pictures)from thin black and brown threads, as well as the "ropes" with a larger diameter from the mentioned cords of ร˜ 0.8 mm and from the cord of ร˜ 1 mm. I stained some ropes and impregnated them with nitro varnish , possibly beeswax.
    Canvas
    I made the sails from a thin cotton sheet, which I dyed brown-red, more or less according to the patterns in the photos. I preliminarily determined the dimensions according to the working drawing on a scale of 1:24. Basically, they are like a trial with the fact that they can be modified.
    According to the working drawing, I made paper cuts of the sails, and according to them I cut out the shape of the sails from the fabric with an allowance for edging. Since "here are not people", I folded the hems on the sails myself, pinned them, attached them with thread and sewed them on a sewing machine.On the outer edge of the hems, I again created a reinforcement with a fine "entl" on the sewing machine, which replaced the laborious sewing of the hems with wire for this set of test sails. Large ships have the edges of their sails reinforced with boltrope, which has a different diameter depending on the type and size of the sail, and for Thames barges, using longitudinal sails, it is always sewn on the left side of the sail. In the end, I sewed only the front face of the foresail for the test. It took me almost the whole afternoonโ€ฆWhen making the sails on the next model, I already used adhesive tape instead of laboriously sewing the edges of the sails.

    ๐Ÿ“ part 11
    29 days ago by ๐Ÿ‡จ๐Ÿ‡ฟ tomarack ( Midshipman)
    โœง 29 Views ยท 7 Likes ยท 1 Comment
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    Forging

    I cut the fittings for attachments and moved from Cu sheet 0.4 mm thick, 4 mm wide strips of the required length according to the drawing. . I welded eyes on them and soldered them with soft solder. Finally, I drilled the necessary ร˜ 0.8 mm holes in the fittings for rivets from steel pins, which will be used to rivet the individual pieces to the sides of the ship. For this operation, I made a "nailer" from thin tubes.
    I made the grommets from Cuprextit* tapes, on which I soldered a U profile from Cu wire. I shaped the shackles from nickel wire ร˜ 1 mm on a jig.
    (*cuprextit - flat grp sheet with glued Cu foil for "printed connections" in electrical engineering)
    A "snatch block", i.e. a pulley for guiding the anchor chain, is attached to the fore stem on the port side. From the starboard side, at the level of the minimum draft( some say above the maximum draft line) a pulley for guiding the "bobstay" of the bow and an eye for the pulleys of the side bow stays is attached.I also attached 2 pulleys for lifting the leeboards.

    Pulleys
    After studying various documents, I finally decided that the pulleys should be functional for such a large model. I therefore bought most of the pulleys for the model from RB Model. At the same time, I bought several brass discs for the production of pulleys, which, as far as the design is concerned, were not in the offer, for example, triple pulleys of the fore stay of ร˜ 10 mm, for which I made parts from brass sheet 0.2 mm, drilled in the fixture.

    I also "turned" several pulley wheels that I was missing using a hacksaw and needle files on my improvised lathe from an electric drill. It's not an ideal way, but they can still be made at least somewhat functional this way. I was the first to make the pulleys for lifting the leeboards and the pulley for the anchor chain (snatch block). Similarly, I made the discs for the double fore stay pulley of ร˜ 4 and 5 mm, the parts were again drilled in the fixture.
    On the bought pulleys, I attached and soldered metal eyes made of Cu wire, single or double, depending on where they will be placed on the model.

    ๐Ÿ’ฌ Re: part 11
    29 days ago by ๐Ÿ‡ณ๐Ÿ‡ฟ jbkiwi ( Fleet Admiral)
    โœง 31 Views ยท 1 Like
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    Excellent job on the pulleys Tom

    JB
    ๐Ÿ“ part 10
    30 days ago by ๐Ÿ‡จ๐Ÿ‡ฟ tomarack ( Midshipman)
    โœง 29 Views ยท 3 Likes
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    The next step was sticking low bulwark along the entire length of the model, at a distance of about 6 mm from the edge of deck. Bulwark I made of balsa 4 x 20 -25 mm, and glued with help of plywood template to the deck.
    It made me a problem bending the bulwark in two planes. I solved it by cutting incisions with handsaw to wooden strips from inside the bending. Spacing of incisions about 3 - 5 mm to about the half of the depth profile bend and sanding from the bottom side. This procedure but then requested a larger amount of putty. Balsa profile soaking into the water I could not use, because the balsa profile literally fell apart .
    For reinforcement I drilled vertical holes with a diameter of 0.8 mm through the balsa bar, to which I inserted through and glued thin bamboo splinters until the holes in the deck, provided reinforcing the positions of the railing.
    (I made it like Kimosuby on his model of Lady Daphne ).
    After sticking I have cut openings (according to the drawing ) through the bulwark for water drainage at deck level.
    I cut out the wooden posts and knees of the bow anchor winch from 5 mm maple boards and stuck on the bow in place.

    In the place of mainmast shrouds fittings and bushings for the side leeboards I'm stuck reinforcements from little pine wedge 10 x 25 x 80 mm.> Pict 24
    On bulwark I stuck at bow and stern increased railings, protective bowboards and quarterboards of spruce beams 2x15mm .
    All parts of bulwark again I impregnate with a diluted epoxy. After hardening epoxy I sprayed hull with filler and repeated sanding both areas from outside and from the inside of bulwark . In place of passage of the leeboard pin I taped Al tubes with a diameter of 4/6 mm as bearing at deck level.

    I applied a sealant and resurfaced in the area. After resealing I drilled holes ร˜ 5 mm beside the stem. From the starboard side I made a notch to bulwark for the bowsprit ,at the port then notch for guiding the anchor chain, which at the barges, did not pass pass through classic anchor chute through deck, but was routed through the auxiliary roller (snatch block) posting usually at the port side of stem.
    I stuck on the stern reinforced beam and drilled holes into it to pass the sheet of the mizzen sail . I impregnate all again with diluted epoxy, applied putty and airbrushed the filler.
    I applied putty at deck several times and sprayed the filler in addition to the places where it comes to stick the front winch, bow companionway and at the end sanded the deck again
    I applied putty to the entire hull couple of times , sanding it and then sprayed the filler again several times . In between tI sanded the hull repeatedly.
    At the end I sprayed the hull with silver gray spray paint. Finally, they were applied different color bands - sheer strake below decks green , bulwark on the outside with black paint and the inside yellow-orange. Bowboards and quarterboards painted white and stern finally also green.
    Finally, I cut out of cardboard decorative labels for the name of the ship. I impregnated it with a nitro lacquer . After drying, I wrote at it new Champion model correct name with Humbrol enamels . and these I glued at the model.
    So it happened that from from that moment on the day of March 23, 2016 my model bears the the name Capricorn.

    ๐Ÿ“ part 9
    30 days ago by ๐Ÿ‡จ๐Ÿ‡ฟ tomarack ( Midshipman)
    โœง 29 Views ยท 4 Likes
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    Mainsail and Vangs Sheet lead, Horses

    To deck forward of the back cabin I gradually drilled 3 holes ร˜ 4,2mm. Through these holes I stretched and stuck Bowden tubes so that it protrudes about 15 mm above the deck. These then lead sheets from servos to mainsail and vangs
    Before the tubes is placed the main horse made by from wooden log with a diameter of 8 mm, after which it moves mainsail runner . Round timber is formed in double slight arc and fixed by metal clamps to wooden consoles. These consoles are glued and riveted to the rear deck about 4 mm from the railing ..
    Before the main mast is the fore horse from 2 mm dia brass wire.
    Foresail sheets are set free on it via chain loop , moving freely from one side to the other, as well as for large barges.
    Jib sheets are controlled by servos located in the front cargo hatch .Through the deck are led again by using the Bowden tubes.

    The Leeboards

    Side fins made from aluminum sheet metal. 2 mm. I cut out sheet according to the template aligned, and roughen the outside and from the outside. I stuck gradually spruce beams 2x12mm ,according to the draft. I used for bonding the fine foam polyurethane adhesive.
    After seizing I cut out protruding beams and resurfaced along the outline of Al profile
    the top side of deckings I sanded with surface grinder and impregnated with epoxy diluted with acetone to a desired viscosity. (first you need is add and mix hardener, then It is also possible to use acetone or cellulose thinner C6000)
    After curing, I again recut wooden surfaces and stuck cardboard strips to imitate the forging ( cardboard or thin air of plywood 1 mm thick) which I painted using nitro-email surfacer -. I drilled holes necessary for axes and shackles.
    Leeboards I painted after finishing with filler, slightly resanding and re-painted the filler from both sides. And finally sprayed silver gray, like the hull.

    ๐Ÿ“ part 8
    30 days ago by ๐Ÿ‡จ๐Ÿ‡ฟ tomarack ( Midshipman)
    โœง 29 Views ยท 3 Likes
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    Stern cabin

    The entire rear superstructure, except companionway cover and steering mechanism I painted with filler, sanded and painted a color - gray roof and sides tan ..
    I then made the lower deadeye forging for mizzen sail of the Cu sheet thickness of 0.3 mm, soldered an eye and riveted to the sides of the superstructure and then painted green.
    Both tabernacles I finally painted green acrylic paint after sanding , rear mizzen tabernacle I screwed to the roof of the back cabin.
    At the main mast tabernacle I attached the winch with two axes with conical coils connected by gears.
    In a similar way, I made a bracket from Cuprextit 1 mm for foot of bowsprit, which must allow the lifting it at least to the stem level nearly perpendicular to the surface.
    Again, painted green.
    Forging for the lower deadeyes and shrouds were made out of copper strips 0,4 mm thick. Then were shaped eyes on them and soldered . Fairleads I made from copper wire ร˜1,6mm which were shaped like ears and soldered on Fiberglass copper coated base (Cuprextit).

    ๐Ÿ“ part 7
    30 days ago by ๐Ÿ‡จ๐Ÿ‡ฟ tomarack ( Midshipman)
    โœง 29 Views ยท 3 Likes
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    To control the mainsail sheets , I bought a 6-turn SW5513-4MA sailwinch servo (by Hobby King) with drum and fastened it to the base. Auxiliary silon cord I stretched between two pulleys, one fixed , the other suspended in an aluminum holder of U profiles . It w fixed at a runner on a steel rod from which will lead sheets aboard to the runner of mainsail .< servo reel I did using servotester .. This seems the most important thing for setting the servos in the model, which would otherwise have to do with switched RC apparatus and even with the possibility of damage to the servo.
    Nevertheless, to control the sheets of the mainsail, I recommend using a lever servo, as Peter Simmonds advised me when building next barge model .
    The mizzen sail was to be controlled by both servos and depending on the position of the mainsail by a transmitter mix as recommended by Mr Ivor Bittle. This should help improve the controllability of the model.
    Still, I finally had to go for a simpler design,there was little space for everything, and the sheets of the mizzen sail are mounted directly on the rudder blade now, as usual in the tsb models.
    The next step was making a base for servo sheets for foresail,and jib sails located under the front cargo hatch.
    As the last was making a base for the servo control for "vangs" , located in the main hatch .
    Last picture - recommended> Peter Simmonds lever servos for main sheet and vangs in Veronica model.

    ๐Ÿ“ part 6
    30 days ago by ๐Ÿ‡จ๐Ÿ‡ฟ tomarack ( Midshipman)
    โœง 29 Views ยท 4 Likes ยท 1 Comment
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    Then I gradually started to make details of the on-board equipment. As the first of the series but came the rudder.
    The rudder of the two halves from 4 mm plywood is glued together to the beam ( cross-section of 10 x 10 mm) , so that a gap ( around 1 mm) remained between the side parts to allow the insertion of the extension part. To the beam come attached the hinges of the rudder and the fork for connecting rod from the servos. It is similar to the rudder construction as Kimosuby describes in his post here. The extension part will be made of fibreglass 0.8 mm.ย (Pict )I gave to main fin ( cut from the 8 mm plywood )ย ย  a little " hydrodynamic" shape and then soaked acetone diluted epoxy. To the fin comes to attach a lead bulb from two half lead castings about 3 kg together.
    In early August 2015 I started to glue parts of the back cabin and the cargo hatch covers again from 3 mm plywood. After sticking directly at their places on the model I have these parts again soaked with epoxy.ย ( following pict.)
    I have cut a skylight from 0.8 mm air plywood . First I stuck the rim from skewers 3x3 mm around the hole for a skylightย . I stuck to them side pieces and then a roof with windows up to them .
    Like the skylight I glued companionway. First, I stuck the rim from skewers 4x4 mm and to it side panels of 4 mm mahogany veneer. Veneer was crudely cut, so I had first grind the veneer to a thickness of 3 mm. It was not until after that I could cut side panels and front part from veneer.
    I stuck the same rim at the rear of the the cabin roof. To this rim will be stick the cover of the rudder head and rudder connecting rods
    Large cargo hatch I covered with 1mm balsa sheets , from the bottom I have reinforced the coverย ย  adding ribs from balsa (4x4 mm). On both covers (fore and main) I glued then a firstly green ,but at the end brown cloth , simulating heavy canvas (brezent fabric - as says my friend Zdenek (a former naval officer)

    ๐Ÿ’ฌ Re: part 6
    30 days ago by ๐Ÿ‡จ๐Ÿ‡ญ Mike Stoney ( Captain)
    โœง 34 Views ยท 1 Like
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    Hey Tom!
    That looks sensational! Congratulations!
    BB Michel-C.
    ๐Ÿ“ part 5
    30 days ago by ๐Ÿ‡จ๐Ÿ‡ฟ tomarack ( Midshipman)
    โœง 29 Views ยท 2 Likes
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    On the improvised lathe I made wooden models for lead bulb (I used dry lime-wood branches) .

    More detailed text was repeated in section 5b

    ๐Ÿ“ part 5 b
    30 days ago by ๐Ÿ‡จ๐Ÿ‡ฟ tomarack ( Midshipman)
    โœง 29 Views ยท 5 Likes
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    During the summer months (besides working in our garden) I used some free time and began preparing the casting of lead bulb.
    On the internet, I found a suitable program for designing the shape and size of the lead "bombs" so that as a result of the burden of approx 3 and 4 kg.
    => see >ย http://www.onemetre.net
    > go to > Design
    go to> Marko's bulb calculator <
    the vertical line indicates the center of gravity of the profile
    preview Bulbcalc as an example .. last 3 pictures
    Please read the entire chapter regarding the load (lead bulb). I will be happy to answer any questions.
    A small note - when designing lead bombs, it is possible to use a printer for output. That's why I was limited when designing the length of the bomb by the possibilities of the printer - a length of 28 cm for A4 format.
    On the improvised lathe I made wooden models(I used dry lime-wood branches). I impregnated these models with wax, then made mold in plaster of Paris (gypsum).To strengthen the material of the mold, when mixing the gypsum mixture with water, I added about 1/4 of the volume of the liquid, an adhesive based on Polyvinyl Acetate Dispersion (PVAc). It worked very well for me, the form is "almost unbreakable". But the mixture hardens more slowly. Wooden models were immersed longitudinally till their half in plaster. The models were cautiously removed after hardening plaster , and the molds were then let dry completely. Drying moulds in the sun lasts at least 14 days. When you double-click at the dry mould, the plaster of Paris must "ring".; only then the mold is ready for casting lead.
    The necessary amount of lead I gradually melted and cast into molds,ย After solidification of the lead I grabbed with pliers protruding wire and removed easily half of the lead bulb quickly from the mold. The result of my work were four lead casts of the required weight. For Capricorn I chose a lighter bomb weighing about 3 kg, (halves 2 x ร 1.5 kg).
    ย I cut off the protruding wire and the castings were purified by sandpaper, and contact surfaces I have aligned with a file
    I filed the castings on the contact surfaces and ground them flat. Because the castings extended beyond the outline of the fin, I cut and glued an 8mm balsa wedge in the place of the overlap of the fins so that it filled the gap between the castings with the given thickness of the fin, and slightly exceeded the outline of the castings. After the glue hardened, I lightly sanded the whole thing. I painted both halves of the load with epoxy 1200, as well as the fin in the place where these will be glued.
    I pulled everything together with PE tape and let the glue harden. After unwinding the tape, I filed the balsa wedge into the outline of the finished load - the bomb. This was followed by sanding and laminating with glass fabric. In the end, I sealed the whole thing again several times, sanded it, and finally sprayed it 4 times with a filler, as a base for spraying.. Last, I sprayed the entire fin black.
    The fuselage of the model had already been repaired and then followed by another test in the bathtub.ย But I found another unexpected problem .. against my expectations empty hull has more dive on the bow than at the stern.
    I used lead castings to balance the fuselage. This way I also found their location, on which they will be attached to the fin.
    Against theoretical expectations, the load must be moved further backward.To a model with a length of 110 cm, the center of gravity provides a distance from the nose of about 42 cm(if I'm not mistaken), with my model, but it is 55 to 60 cm from the bow.
    The model building then continued. The deck I made of 3mm plywood, I stuck รญt to place, and I also stuck sheer strakes. All this I laminated again with glass fabric 100 g / m2.
    Then I glued coamings around the hatches made of 3 mm plywood. From the outside I laminated with glass tape again, and the inside of the coamings I Impregnated with diluted epoxy.

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