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Nick_Karatzides

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  1. Been long time since last visit, huh? Well, let's remember some hobby fun again. The objective is to build two different diorama scenes for two different versions of the same helicopter: One for the full fuselage version of the 1/18 scale Flettner Fl-282 V21 Kolibri model kit and, A second for the cutaway / fabric stripped version of the 1/18 scale Flettner Fl-282 V21 Kolibri model kit. According to plan, both of them would include few additional features without distracting viewer's attention, keeping the Kolibri helicopter as the main protagonist of the story. Starting with the full fuselage version, the addition of a WWII era Luftwaffe's 200 litres fuel drum with a handpump attached, few 20 litres canisters and a filled bucket left on ground, seemed good idea to me in order to present a short refueling scene. Rivet counters may say that the presence of a 200 litres fuel drum right next to the helicopter may look unreal or “too much”. Well, considering that the twin seat Fl-282 V21 helicopter had two 25 litres cylindrical fuel tanks mounted externally on both sides of the pilot seat (while the main 105 litres fuel tank installed on previous versions removed to host observer’s rear seat), a number of only 2 or 3 fuel canisters could be just enough to do the job. I am not sure about the official refueling procedures followed by Luftwaffe for the Kolibri helicopter during operational conditions & which were the appropriate method followed by engineers & maintenance personnel. Did they park the Kolibri close to area where 200 litres fuel drums stored and later pumped fuel directly into helicopter’s tanks through a hose? Did they move (carrying on a truck / cart) the 200 litres fuel drums next to the helicopter’s parking area and later pump fuel inside tanks? Did they fill helicopter’s tanks with hand-carried smaller 20 litres canisters & funnels, brought from main fuel storage area, next to parked Kolibri? IMHO, all the above (and many others) sound quite possible scenarios. Since we all have seen WWII era pics showing airfield ground personnel using a big variety of methods, from operating Opel refueling trucks, to mule / donkey driven carts or poor maintenance personnel carrying 20 litres canisters by hands, I think that having few 20 litres canisters left into the diorama scene and same time a 200 litres fuel drum feeding the helicopter tanks directly through a hose, could be considered as realistic and not just an “artistic accepted” option. Meanwhile, the rotor blades for both versions attached on their rotor heads as described into the building manual (click HERE for the PDF formated file) through pages #88 to #94. Parts sprayed over with AK interactive AK768 primer to spot mistakes and prepare for paintjob. I did a visual inspection and shot some pictures. After overall primer, rotor blades dry fit tested to ensure that all individual components could be later combined together as an overall built model. I admit that it’s not easy to handle Kolibri scale model and find best angle for photoshoot on bench, while having the rotor blades (measuring approx 70 cm from one wingtip to the other) attached.
  2. @ alancmlaird, Having already designed and produced / 3D print a VW engine for a customer who asked it under 1/9 scale, I guess that it would be possible to re-size it down to 1/72 scale too - ofcourse, you should not expect the detail level as seen on a bigger size scale model. On the other hand, I really cannot see how a VW car engine would fit on a gyro and also look realistic. Maybe you should try an aviation related engine if planning to add it on the above mentioned Wallis gyrocopter? Anyway, if interested, feel free to contact with my colleagues who run the Anyuta 3D online shop, hoping you 'll find best product (custom-made also possible ofcourse) for you. Regards, Nick
  3. No problem about it. There are other options available for you, as long as you like to experiment and do some scratch work too. The first five WA-116s were built by Beagle Aircraft at Shoreham on 1962 and three of them were for evaluation by the British Army Air Corps. In 1966, one of the previously mentioned Beagle built WA-116s, registered G-ARZB (nicknamed as “Little Nellie”), was modified for use in the 1967 James Bond film “You Only Live Twice”. Few Wallis autogyros have been operated privately, with nearly all of them being used for research and demonstration flying by Ken Wallis himself. The Wallis WA-116 Agile was powered by a McCulloch Model 4318A four cylinder horizontally opposed air cooled engine, providing a top speed of 185 km/h and a range of 225 km. After building first nine single seaters, the construction of a two seat variant the WA-116T was begun in 1969; Ken Wallis tested a four blade rotor and finally produced the WA-116F with which he won the closed circuit world record in 1974 in the 670.26 km category. Wallis autogyros have been powered by various types of engines, within the range 72 hp to 160 hp (the latter is used in the two seat Wallis WA-122) and have been employed for research programmes, including one promoted by Sperry Radar. In 1983 development of a production version, powered by a Weslake engine, was under way in association with Vinten Ltd. When I start studying the Wallis autogyro, I had the impression that all Wallis autogyros, were all same - at least identical. The fact that each one of them is not a product of a factory assembling line but the result of custom hand work, shows that there are plenty of differences between them - obvious differences or just small details identified after careful observation. For example the autogyro represented into following picture as seen at EGBK Sywell, UK during the PFA Rally, back in 1973, is the s/n G-ARZA (ex-registered as XR942 and painted dark olive with official British Army markings), one of the five first Beagle built WA-116s, typed as "Wallis WA-116/Mc Srs.1" (the “Mc” means McCulloch engine and the “Srs.1” goes for series 1). The three of these first five Wallis autogyros were produced on behalf of British Army Air Corps for further evaluation and had no cabin cover. After a brief military carreer, these three Wallis WA-116/Mc Srs.1 remodified, repainted and received new civilian callsign register. One of them, was destined to become very famous as "Little Nellie" after appearing in the 1967 James Bond film “You Only Live Twice” movie. Research based on the published files & info, shows that the serial numbers of these first built "Srs.1" are the following: G-ARRT was the first Beagle Aircraft built prototype, first flown on 2 August 1961 at Shoreham. Aerodynamic cabin cover added later. XR942 initially built on behalf of British Army Air Corps and later renamed to G-ARZA. Aerodynamic cabin cover & beacon lights on rudder fin added later. XR943 initially built on behalf of British Army Air Corps and later renamed to G-ARZB. Aerodynamic cabin cover & dummy rocket launchers added later to become the widely known 007 James Bond’s "Little Nellie". XR944 initially built on behalf of British Army Air Corps and later renamed to G-ATTB. Aerodynamic cabin cover and longer main rotor blades added later. G-AXAS was the last built "Wallis WA-116/Mc Srs.1" and was Ken's favorite, since he was usually demo flying with it at Reymerston Hall Dereham, UK until his last days. The tail rudder fin was replaced on 1986, by a Wallis WA-122 spare part. That was NOT a Wallis autogyro. It looks like, but its not. The "unpowered version on a towline" is not a gyrocopter / autogyro at all. It's a kite! As said before, there were differencies - mainly on engines. No they did not. The "flying vehicles" you mentioned, were kites! There IS difference between a helicopter, a gyrocopter and a kite. Anyway, for anyone who is interested, the Wallis autogyro has been presented HERE in forum as 1/18 scale Wallis WA-116 Agile autogyro scratchbuild model. For scale modelers who are like to build the model, it is available as 3D printed scale model under 1/16 and 1/18 scales by Anyuta 3D printed scale models into following links: 1/18 scale Wallis WA-116 Agile autogyro model kit, 1/16 scale Wallis WA-116 Agile autogyro model kit. Have a look on following pics of the kit parts and complete buit model.
  4. There is no difficulty and no essential difference as for handling and assembly. Maybe all you need to do before, is to thoroughly clean the individual parts of the kit. You see, some kit parts may appear slight traces of oil, which is absolutely normal. This oil is actually left after the 3D printing process was finished and the kit parts been removed from the printer tray to be washed into an ultrasonic oil bath and later an ultrasonic water bath and might escaped the clean inspection and dry by hand procedure. It can be cleaned easily by washing parts with water and dishwasher soap and clean with an old toothbrush gently. As additional advice, I would recommend use on CA glue only, since the liquid glue (perfect for styrene parts) seems ineffective on plastic used for 3D printing the scale models. To explain in details for people who are not familiar with 3D printing: The kit parts are produced with a high-precision & high-cost "ProJet HD 3000" machine for creating custom made-to-order products. The 3D printing layers can be as thin as 16 microns. Matterial used, is the best available (and most expensive too) in market for such scale modeling use: It is called Frosted Detail or VisiJet SR 200. It is a UV light cured acrylic polymer plastic material with ± 0.025 mm accuracy for every 25.40 mm. It's actually an organic mixture, consists of 55% triethylene glycol dimethacrylate ester and 45% urethane acrylate polymer. The 3D printed items produced with this "Frosted Detail" matterial can be as thin as 0.3mm (or less in some cases) and the machine is able to accurately replicate embossed or engraved details (for example rivets, panel lines etc) as high or deep as 0.1mm (one-tenth-of-milimeter). This Frosted Detail (or VisiJet SR 200) plastic materials is printed using the “MJM” (Multi Jet Modeling) process. During this MJM process, cartridges of acrylate and/or wax material are heated and the plastic material is fired in ballistic micro droplets from a multi-chambered print head containing hundreds of Piezo jets. Molten plastic is deposited onto an aluminum build platform in layers using several nozzles, essentially like a large print that sweeps across the build layer. As the heated material jets onto the build plate, it solidifies instantly. After each layer is deposited, it is cured & polymerized by a wide area UV lamp. The next layer then applied, and through this repeated process layers of thermoplastic build up into a model. This method can print durable plastic parts with a high level of detail and accuracy as well as burnout materials and real wax parts for casting. Material utilize a waxy support material that is dissolved after printing is completed.
  5. The helicopter model secured in place, by wedging the pins under the wheels into holes that had been already opened on concrete (that's the reason wheels had pins underneath). Once the Kolibri placed on display, each one of all these previously mentioned 1/18 scale items & diorama accessories also secured on ground with hidden metal pins and glued with transparent silicon. Finally, few more “maintenance & refueling area” related items (such as one 1/18 scale WWII era fuel hand pump, a set of 1/18 scale wheel chocks, some 1/18 scale wooden crates and a couple of 1/18 scale water buckets) also prepared to be placed on concrete display base. A last moment’s addition, an also 3D printed 1/18 scale WWII era Fahrrade M30 reconnaissance duty bicycle model, prepared for the diorama display. All the above mentioned diorama accessories are listed into Anyuta 3D products catalog and available for sale under various scales and sizes.
  6. CHAPTER XII - Concrete apron display base construction When I started this Kolibri project for a collector located in Kiel, Germany and later built more identical helicopters for other customers and my own collection at home too, I was concerned about a proper display option, on which the model would be placed. My goal is to build up a simple diorama scene, which looks like a “maintenance & refueling area” on a forwarded airfield. From an artistic point of view, a “maintenance & refueling area” scene might possibly dictate everything to be into a state of complete engine oil ‘n’ grease messiness. My goal is to keep the Kolibri helicopter as protagonist into the scene, while filling the empty space with few “maintenance & refueling area” related items, to maintain a visual balance. What I am actually trying to present here, is an intentional setup to show scale model’s details through opened maintenance panels, opened hatches, removed engine unit etc without extreme diorama action, nothing that could possibly distract viewer’s attention from the Kolibri helicopter which is always the main protagonist of the story. Any other item should be standing as an uninvolved walkon to simply complete the directorial picture. While scale model painting was underway, I thought as good idea to place the Kolibri helicopter scene on a “grass airfield” area. My opinion had been probably shaped (aka influenced) by viewing WWII era pictures, where the Flettner Fl-282 V21 Kolibris were stationed on the fresh green grass. Unfortunatelly, the problem that would arise from such a choice, is that the (already painted green) helicopter would be visually lost into this greenish backround. Due this reason, the idea of placing the Kolibri model on grass abandoned and the idea of a concrete covered airfield apron area (with just a few short grass sprouted between concrete slabs) where pre-flight activities were done, seemed much better. The scene would require at least a 450 x 350mm display base, considering that helicopter measures approx 357mm long and 138mm wide, without counting the rotor blades with disc diameter approx 700mm each. Those who have read my previously uploaded projects, might remember that I prefer using plaster powder to build the section that recreates the ground, especially if it is asphalt. However, the 450 x 350mm dimensions of the scene dictate plaster quantity more (and therefore heavier) than usual and for this reason I chose to use another material, because the goal was to build a airfield display base instead of weightlifting equipment for champs. For this reason, I decided to follow a different way, by replicating concrete covered airfield apron with cork sheet. I purchased two 500 x 500mm sized & 4mm thick sheets of cork from my local hobby shop, which I cut & shaped around with my Black & Decker 400W / 3000spm jigsaw. The basic idea, is to build an approx 8mm thick & flat surface which protrudes above the polished wood display base, on which short vegetation (grew between the concrete slabs) and diorama accessories (such as maintenance tools, fuel canisters etc), will be added later. As soon as the 4mm thick sheets of cork identically cut into shape, sandwitch glued and the concrete plaques were lined, I used my airbrush to paint it. As I usually like to do, three different acrylic paint layers were applied on the concrete apron surface. First, mat black colour covered the area and then lighter greyish and earth layers applied, while airbrushing in almost zero degrees angle, to let the darker areas between the concrete plaques remain naturally dark. The concrete apron surface was paint with different greyish & earth tones and as soon as the acrylic colours dried, I tried some drybrushing on selected spots using sand tones. Concrete areas on which the oil drums, the fuel canisters, the under maintenance radial engine etc will be placed later (probably resulting oil & fuel stains on ground), painted differently with more yellowish shades to replicate sawdust spread to absorb leaked oil & fuel. As for the vegetation that grew between the concrete slabs, I used some Heki static grass, secured in place with water based white glue for wood which becomes transparent when it dries. When it looked OK to me, I sprayed over with Humbrol enamel matte coat, to seal the paint & vegetation result so far and left it overnight to dry. Meanwhile, some of the earlier described 3D printed items (unrelated to the helicopter structure) such as few 1/18 scale 20 litres fuel canisters, one of these 1/18 scale 55 gallons oil drums and one of these 1/18 scale 200 litres fuel drums as used by Wehrmacht, Luftwaffe & Kriegsmarine during WWII with “Kraftstoff 200L Feuergefährlich Luftwaffe” & “Kraftstoff 20L Feuergefährlich 1941” inscriptions engraved or embossed on side, also got some paint, dirt & weather effects. All the above mentioned diorama accessories are listed into Anyuta 3D products catalog and available for sale under various scales and sizes. The previously mentioned 1/18 scale 200 litres fuel drum received a basic layer of Life Color UA505 RLM 79 Sandgelb II / Sand Gold II acrylic paint and the 1/18 scale 55 gallons oil drum painted with Life Color UA504 RLM 02 Grau / Grey acrylic paint and allowed to dry overnight. Once the acrylic base coat has cured, both drums got some weathering, paint scratches and rusty chipping effects while using the sponge technique to give visual interest to the base colour. To achieve best results, I did use a fine textured sponge like those used for packing of electrical items. Fresh rust marks also added in some selected points, with some of the Life Color UA704 Rust Light Shadow 2 acrylic. Using a fine tipped brush, the Light Rust Brown & Dark Rust oil paints by 502 Abteilung & AK Interactive series painted in vertical lines from various chips and scratches added earlier. Once the oil paints had been allowed to dry for a short while, a brush dampered in White Spirit used to blend and soften these streaks for a more subtle effect and obtain visible signs of wear & oxidation.
  7. CHAPTER XI - Assembling individual parts As soon as most individual 3D printed parts on both “full fuselage” & “cutaway” scale model kit versions were already painted & weathered, everything should be combined and assembled as an overall built miniature. Having already installed the rudder fin and the two horizontial elevator fins on the “full fuselage” version model’s tail, the gear box unit was next. Following instructions described into the building manual (click HERE for the PDF formated file) through pages 33 to 37, all the four pins on gearbox unit should be simultaneously aligned onto the upper frame’s slots and same time linked downwards with engine’s transmission shaft, as shown on following pictures. Here is a detailed view of the correctly installed gearbox unit as seen underneath the fuselage cover. Notice that the forementioned gearbox unit is linked (marked with red circle) with previously assembled engine’s transmission through a shaft coupling. This is how the assembled block of rotary engine, transmission unit, cooling twin blade propeler fan, drive shaft & upper gearbox unit should look like when correctly fit into each other. Notice that tubular frame is not visible here for better example view. Both “full fuselage” & “cutaway” scale model kit versions are equiped with fixed non-retractable tricycle type undercarriage with a steerable nose. The tubular shaped struts & the central supporting section anchoring points aligned on proper U-shaped slots found on the lower fuselage area. Following instructions described into the building manual, the upper & lower anchoring points on each tubular landing gear strut end should be simultaneously aligned onto the tube frame’s U-shaped slot (marked with red arrows). Successful assembly of main landing gear section will positively affect process to follow - a side tilted helicopter model, would look completely unreal. This is how the fixed non-retractable tricycle type undercarriage frame should look like when the parts correctly installed on the fuselage frame. Everything secured in place with a drop of cyanoacrylate super glue. To add some weathered look on fuselage areas (doped fabric covering over the steel & wooden frame on real helicopter) and replicate parts like being dirty, dusty or sunfaded, I appplied different shades of dark brownish pigment powder, trying to blend them nicely to look artistically accepted and create 3D-alike effects on flat surfaces. The results on model may not look so “strictly realistic” comparing to the real world objects, but IMHO scale modeling has to balance between realism factor and artistic expression. I admit that adding (extensively in some specific areas) pigment powder, may not accurately replicate the reality, but it looks artistically attractive and becomes easily accepted by visual subconscious. The main advantage of the pigment powder shades is that the already painted scale model gets some nice weathering / lighting effect tones. On the other hand, the big disadvantage is that once the pigment powder settles on the model’s surface, it should not be touched to avoid smudging. To overcome this problem, modelers usually secure the pigment in place by carefully soaking the model surface with modeling fixer. However, even after applying modeling fixer, it is not absolutely safe to touch the model. I tried a different approach and used Winsor & Newton’s fixative for charcoal & pastels (instead of modeling fixer) over pigments. Although similar, the Winsor & Newton’s fixative is different from the modeling fixer. The Winsor & Newton’s fixative solution (available in 75ml and 500ml bottles) provides protection of charcoal, pencil, pastel & chalk drawings - it is mostly used by painters & pastel artists to seal the final result of their work. Although the model paint gets glossy after Winsor & Newton’s fixative applying, the good news is that model can be sprayed over with final matte coat after securing pigments with Winsor & Newton’s fixative, without leaving disastrous spots or milky stains on model (as usually happens when applying matte coat over modeling fixer-sealed pigments). Once the Winsor & Newton’s fixative dried, the (glossy) outcome had tonality differences because pigments applied earlier and looked like been faded by the sun, fouled by dust and stained by fuel & oil. As previously mentioned, the glossy look is not actually a problem, since the model can be sprayed over with final matte coat later, while keeping all the pigment shades. The wheels attached on undercarriage, according instructions described into the building manual. The U-shaped nose wheel supporting fork, pinned into the shock absorber slot while making sure that axes are aligned, as shown in following picture. Notice that nose wheel is tilted accordingly to the rudder fin (which is already installed) as previously explained. The twin 25 litres cylindrical fuel tanks (mounted externally on both sides of the pilot seat), attached on frame by plugging pins into proper slots as shown on the following pictures & secured in place with cyanoacrylate super glue. Since these cylindrical fuel tanks are made hollow, the sealing caps can be removed if building a refueling diorama scene. Notice the details marked into the red circles - this is how the cylindrical external fuel tanks should look like when correctly mounted externally on both sides of the cockpit area framework. Here is how a semi-built “full fuselage” scale model kit version looks like as seen underneath, after few of the kit parts installed. More parts such as the side & lower fuselage door panels, the rudder pedals & control levers in cockpit area, the instruments panel, the rotor heads & blades etc, will be attached on main frame later.
  8. CHAPTER X - Parallel build challenge? Accepted When I started this project almost two years ago, I had in mind to also present the “cutaway” model kit version step-by-step WIP, as soon as the “full fuselage” model kit building would have been completed. Actually, both versions already built multiple times as commision work for collectors (for example click HERE to see both versions frames placed side-by-side, while painting process) and I only had to write the text and later attach the pictures shot during assembling & painting process. 1/18 scale Flettner Fl-282 V21 Kolibri model kit - CUTAWAY version 1/18 scale Flettner Fl-282 V21 Kolibri model kit - FULL FSG version Considering that over 130+ model kits of both versions sold since Anyuta 3D produced the very first 3D printed V6 version kit under 1/18 scale on early 2014 and due to the fact that the V21 cutaway version became quite popular the last few days, I am now thinking to change a little the basic plan and let the cutaway version step-by-step building edit into the full fuselage version WIP and present them both as a parallel project into a single forum thread. As you all understand, the “cutaway” version is actually based on the previously released “full fuselage” model kit, but more than 50% of parts should be CAD designed from the start in order to achieve best results. Although both versions are accurate miniatures of the Kolibri V21 helicopter under 1/18 scale, each one follows different assembling methodology. During the CAD phase, the individual kit parts designed in such way to be as easy as possible for the average modeler to build the model. To do so, the total number of tiny parts reduced (as possible) and different components combined into one part only. IMHO, building something from scratch is not so difficult - after all, we all tried some scratch once in a while. On the other hand, designing a helicopter model from scratch, exploding it into 60+ parts and make each one of them possible to get re-assembled & combined all together in order to create a miniature, is not a piece-of-cake. Speaking of a “cutaway”, the design difficulty factor gets multiplied. If you download the 102-page "full fuselage" and the 67-page "cutaway" PDF formated building instructions manuals, you'll notice the building process differencies on the first pages. Both versions have exact same dimensions when models fully built, but each assembling process differs a little. For example, as shown into following picture: The "full fuselage" version kit is equiped with four full-length rotor blades (measuring approx 28 cm long each), but the "cutaway" version has the short / chopped rotor blade parts (marked into red ellipse), to simulate the Kolibri found by British Army and now preserved by Midland Air Museum, in cutaway condition. The "full fuselage" version's main tubular frame is a little shorter (marked into red circle in following picture) than the normal-length “cutaway’ version's tubular frame. This is because the "full fuselage" version's rear fuselage cover part (which simulates the doped fabric covering over the steel & wooden frame and moreover has the vertical stabilizer attached on) should be dragged along the miniature's wooden frame, until reached down on the transmission pivots. So, as you understand, few milimeters of empty space are needed to ensure the appropriate contact. The "full fuselage" version's main tubular frame is equiped with a "sleeve" (marked into purple ellipse in following picture) over the front tubular frame. Actually this is a bracket made of wood to support avionics & radio either side of the pilot at cockpit area. This "sleeve" part as well as some others like eg batteries, avionics & radio, 25 litres cylindrical fuel tanks mounted externally on both sides of the pilot, seat cushions etc are also missing from the "cutaway" version. The undercarriage support (marked into blue ellipse in following picture) is different on each version. Although both versions will show the same on this undercarriage support area when models are buit, the “full fuselage” version's main tubular frame is missing this part, since it is already attached on the rear fuselage cover part. The vertical stabilizer of the “cutaway” version kit is offered as a separate part, which should be glued on the wooden frame. On the other hand, on “full fuselage” version kit, the vertical stabilizer is already attached on rear fuselage cover and offered as combined items. After studing the available reference (few hundreds of pics, blueprints, slides & negatives, videos, technical data and original Luftwaffe's text documents) kindly offered from a variety of sources such as Deutsches museum flugwerft schleißheim, Hubschraubermuseum Bückeburg, Midland air museum, a fellow modeler from Germany whose grandfather was a worker in the Anton Flettner Flugzeugbau GmbH factory at the time when the helicopters manufactured, Mr. Steve Coates author of the "Helicopters of the Third Reich" book and ofcourse Mr. Google (modeler's best friend), the already existing CAD digital file converted to Kolibri cutaway. Now, the model is ready to be forwarded to the 3D replicator and become an actual physical object under 1/18 scale, within short time. Approx 50% of the components are copied & pasted from the already existing full fuselage version and (lucky me) I did not had to design everything from the start. For example, the complex of intermeshing rotor gearbox, the 7-cylinders radial engine, the 24° angled rotor heads etc. On the other hand, all the “wooden frame” parts such as the vertical stabilizer, the rudder fin, the horizontial elevator fins and rear fuselage frame details, were CAD designed from the start. Ofcourse, the cutaway version was also built with all included truss-type welded tubes and drive shaft rods with universal joints attached on frame. IMHO, that was mostly preferred because all basic parts should be accurately pre-installed in place without any glue, putty, sanding etc. After digitally building the Fl-282 Kolibri cutaway 3D model using only mouse clicks, I saved it as an STL - STereoLithography format binary file and forward it on the 3D replicator to start generating the individual parts of the actual scale model. Once again, I used best available tools & plastic material and asked from Shapeways digital fabrication lab (equipped with a high-precision & high-cost “ProJet HD 3000” machine for creating custom made-to-order products), to 3D print it. The 1/18 scale Fl-282 V21 Kolibri “cutaway” model kit consists of more than 40 different 3D printed parts made of matte translucent plastic material - in fact, the kit parts are quite more, but smaller in size are interconnected on same sprue frame which is counted as one part. Kit was CAD designed and 3D produced in such way to simplify assembling process while maintaining necessary details required by the scale size. Following the instructions described into the 67-page ultra-detailed “1/18 Fl-282 V21 cutaway kit building instructions” manual (which can be found HERE as a PDF format downloadable file), the assembling process becomes easy. When printing is finished, the model parts are removed from the tray and placed into an oven that melts away the wax support material. Next, the models are placed into an a ultrasonic oil bath to remove any remaining wax residues, and then a ultrasonic water bath to remove any oil on the model. Final inspection and dry by hand follows for every single model part. Although the ProJet HD 3000 prints in high resolution (16 microns per layer) and can easily produce high detailed parts as small as 0.1 mm, it is better to avoid printing such small parts because they could easily get lost while washed into ultrasonic bath later, for wax residues removing. Each complete model kit takes about 5 to 7 days to get produced after order due to increased workload for 3D printed manufacturing demand in Shapeways factory. As soon as 3D printing process completed, the produced parts were cleaned & checked for broken parts or imperfections by Shapeways 3D printing lab specialized personnel. Later, everything carefully packed and shipped to my home address using UPS 24hrs delivery service. Once again, I was happy to hold my own custom 3D printed model kit, CAD designed with my laptop and later converted to an actual physical object, under my preferable 1/18 scale. Some additional parts unrelated to the helicopter structure, also 3D printed to be used later as part of a diorama scene. For example few 1/18 scale 20 litres fuel canisters, a couple of 1/18 scale 200 litres fuel drums as used by Wehrmacht, Luftwaffe & Kriegsmarine during WWII with “Kraftstoff 200L Feuergefährlich Luftwaffe” and “Kraftstoff 20 L Feuergefährlich 1941” inscriptions engraved or embossed on side, a 1/18 scale fuel hand pump and one 1/18 scale wooden 3-steps ladder as used by Luftwaffe WWII ground crews and technician personnel for ground vehicle & aircraft maintenance procedures. Rotary hand pump used by techical crews & maintenance personnel to transfer fuel from the 55 gallons drums to aircraft & armoured vehicles fuel tanks or into the 20 lt fuel canisters (both drums & canisters are available for sale at Anyuta 3D products catalogue). This type of manual fuel pump used by Luftwaffe & Wehrmacht during WWII. The rotary hand pump kit contains all necessary parts for assembling one fuel hand pump under 1/18 scale. Any extra diorama accessories (hose, 55 gallons fuel drum etc) are not included and should be purchased separately. Although 3D printed models do not differ so much from ordinary kits, the plastic material may cause surprises. Some of the kit parts may feel a little greasy and appeat slight traces of oil on their surface. As I've already described into previous pages, it is absolutely normal. After the 3D printing process was finished and the kit parts been removed from the printer tray to be washed into an ultrasonic oil bath and later an ultrasonic water bath, some oil traces escaped the clean inspection and dry by hand procedure. Parts can be easily cleaned by following one of the following methods: By washing parts with water (NEVER apply water hotter than 50º C / 125º F or you'll be really sorry) & dishwasher soap and brush gently with an old soft toothbrush. Keep in mind that items are only 0.3mm to 0.5mm thin and they are very fragile. Therefore, being very carefull while washing the parts is a necessary. By sinking everything into a plastic bowl filled with White Spirit and leave it there for few seconds or a couple of minutes (max) to wash oil traces. In the end the the kit won’t feel greasy anymore and show an almost complete white colour. Never use anything more "aggresive" than White Spirit. Also, AVOID stove cleaning spray and acetone nail polish remover products - both clean oil & wax but also dissolve the plastic leading to breakage and failure. By using hydrosonic cleaning machine (IMHO, is the best alternative), filled with water & dishwasher soap and repeat procedure if needed. Meanwhile the water will turn cloudy - that’s the wax. It is of utmost importance that the model parts are properly degreased - otherwise the paint will not stick. Small remainders can be removed with a swab or toothpick. For my own 1/18 scale Kolibri cutaway model kit, I decided (since I do not have a hydrosonic cleaning machine) to wash slight oil traces on parts by sinking everything into a 2 litres plastic bowl filled with White Spirit and leave it there for a couple of minutes. Shortly after all kit parts enjoyed their bath into a White Spirit filled bowl, they were washed with liquid soap & warm water, placed on soft paper towels and allowed to dry. After all kit parts washed in White Spirit & water to clean the oil traces, every section of the model has been repeatedly dry fit tested to ensure that all individual parts could be later combined together as an overall built model. When looked OK to me, each part sprayed over with an undercoat mixture of 80% Life Color LC02 Matt Black and 20% Life Color LC37 Matt Burnt Umber acrylic, to prepare the surfaces for the basic paint which about to follow. Later, a very thin coat of Life Color UA503 Light Blue acrylic paint layer applied, very diluted with Life Color’s acrylic thinner in a 30% paint to 70% thinner ratio. The darkest recesses sprayed first, gradually working my way up the frame, keeping to the lighter areas on central parts of each tubular part. Same pattern maintained throughout the entire painting process to preserve continuity with the light source and subsequent spraying sessions continued to utilize very thin Life Color UA503 Light Blue acrylic paint layers as a base to varying degrees because it is the source of the light colour. The tubular frame got gradually lighten with each successive layer as the painting process continued, so the second layer of paint as the medium layer of the base coat, is based upon a less diluted 50% paint to 50% thinner ratio. Then, I added just a few drops of Life Color LC01 Matt White FS37925 acrylic paint into the mixture to lighten up this stage of paint application, being very careful to always follow the established gradation pattern, untill contrast between light and dark started to become apparent.
  9. CHAPTER IX - Rear fuselage section assembly The rear fuselage section on real Flettner 282 helicopter was made of doped fabric covering over the steel and wooden frame. Those who have followed this thread from the start, will remember that the rear fuselage section had already been covered with an overall black / dark brown undercoat and then gradually lighten the surfaces to replicate the way that sunlight hits on large objects, following the Francois Verlinden’s old-fashioned way (which was re-introduced and become popular around the scale modelling community, by its new “modulation” name). The dark undercoat, gradually airbrushed with RLM 71 Dunkelgrün FS 34079 to achieve proper gradations of light, trying to balance between realism factor and artistic expression. IMHO modulation effect does not accurately replicate the reality, but it looks so artistically attractive and becomes easily accepted by our visual subconscious. Custom made water slide decals applied and later everything washed by brushing “Winter Streaking Grime” AK014 filter available by AK Interactive, until the desired colour density is achieved. As described into pages #25 to #27 of the ultra-detailed “1/18 Fl-282 V21 kit building instructions” manual (which can be found HERE as a downloadable PDF format file), the rear fuselage cover part carefully dragged along the miniature's wooden frame, until reached down on the transmission pivots & secured in place with a drop of cyanoacrylate super glue. Steering of the Fl-282 was achieved by a combination of the rudder and differential collective pitch change on the two rotors, but only the rudder could give steering during autorotation since collective pitch was then ineffective (another reason for the large rudder area). Rudder fin (of very generous area), was made of wood and covered by fabric, with max 40° deflection left or right. This large area was necessary because much of it was ineffective due to the poor aerodynamic shape of the fuselage causing rearwards flow separation and turbulence. The vertical stabilizer and the elevators were also made of wood, with plywood leading edge and fabric covering, bolted to fuselage frame. As described into pages #29 to #32 of the ultra-detailed “1/18 Fl-282 V21 kit building instructions” manual (which can be found HERE as a downloadable PDF format file), the rudder fin’s slots should be aligned onto horizontal stabilizer's hinges as shown on the following pictures. I tried dry fit testing before the final gluing & part secured in place by adding a drop of cyanoacrylate superglue. Since the rudder fin can be instaled turned (with max 40° deflection left or right), the servo bars should be inserted into slots & placed as required. Notice that if the rudder fin is tilted left or right or neutral, the rudder pedals at cockpit area & nose wheel, should be also positioned accordingly. The two horizontial elevator fins should be installed by inserting the 1.4 mm Ø pins through side openings of rear fuselage section as shown on pictures and securing in place with a drop of cyanoacrylate superglue. Keep in mind that if the horizontial elevator fins are placed tilted up or down or neutral, the cyclic / KG.13 control stick at cockpit area, should be also positioned accordingly. Under normal conditions, each helicopter’s registration ID was duplicated under elevator fins. After all, there are many photographic evidences certifying this feature, just like the following picture showing the CJ-SK registered Fl-282 V17 helicopter, crashed at Travemünde on April 13rd 1944, while test pilot FliegerStabsingenieur (Luftwaffe Major) Gerhard Geike was attempting a “diving nose-down and then pulling back” technique landing. However, there is a rare photograph of the already mentioned CJ-SN registered Fl-282 V20 helicopter assigned to Staffel 1/196 at Pillau AB as found & captured by the British Army, that clearly shows registration missing under the elevator fins. Luckily, the picture taken before helicopter been brutally disassembled, doped fabric ripped away & removed from fuselage, clipped rotor blades cut off & never seen again since that day and remaining framework wreckage with upper rotor transmission parts transferred back to UK as a War trophy and ended up as souvenirs.
  10. The first two production model kits under 1/18 scale, were 3D designed such way to have the seatbelts & buckles embossed on the crew seat cushions - a tactic that later altered, since customers mostly prefered to add their own harness or leave the miniature helicopter free of straps webbing. For this reason, the seatbelts shown into following pictures were built from 2.5mm to 3.5mm wide masking tape and photoetched set by Eduard, under 1/20 scale. The seatbelts later got some brownish & khaki paint - so as to make sharp & nice looking contrast against the reddish varnished plywood seatboards and the overall RLM 71 Dunkelgrün FS 34079 painted airframe cover.
  11. Those who have followed this thread from the start, will remember that the front fuselage cover had already been covered with an overall dark undercoat and later gradually airbrushed with RLM 71 Dunkelgrün FS 34079 to achieve proper gradations of light. The front fuselage cover patiently awaited the tubular frame painting completion, in order to come the turn to be properly installed. The part carefully dragged in place along the frame tubes, until reached down on the pilot’s seat & secured in place with a drop of cyanoacrylate super glue.
  12. CHAPTER VIII - Crew seats & front fuselage cover assembly Each one of the 1/18 scale Flettner 282 V21 kits contains two crew seats for the pilot and for the rearwards facing observer. The observer’s seat consists of two perforated plywood boards, one for the bottom part fixed on a retractable bracket and one for the backrest fixed on frame rails. Cushions are placed over bottom part & backrest plywood boards to provide comfort. On the other hand, the pilot’s seat consists of a (similar cushion covered perforated plywood board) bottom part only, since he rests his back-pack type parachute against the front fuselage cover. Having just painted the perforated plywood boards and being quite pleased with the outcome, I decided (once again) to deviate from the instructions and skip the cushions installation - after all, the reddish varnished look on plywood boards seems to make a fine contrast with the overall RLM 71 Dunkelgrün FS 34079 and breaks the green monotony.
  13. If the assembly sequence would follow the instructions by-the-book, the two battery packs should be placed on appropriate brackets located on either side of the transmission unit as shown in the picture from the kit manual. Since the original building idea requires to setup the 1/18 scale Kolibri model in such way to look like under maintenance (or refueling) procedure with all the hatches & sliding panels opened or removed, I decided to deviate just a little from the schedule and do something different: To unplug the batteries and place them somewhere else - possibly on some wooden box or the previously mentioned wooden ladder, one of these unrelated to the helicopter structure additional parts which were designed & 3D printed to be used as part of a diorama scene.
  14. Once the radial engine mounting process completed, I would attempt to turn a pig’s ear to silk purse - in other words, to paint the 3D printed cooling fan in such way to look like made of wood. Since (as commented into previous paragraphs) I had not enough reference of the actual Kolibri’s cooling fan, I did what most modelers always do - improvise, hoping that final result would look nice! To do so, I used the Life Color UA716 Wood Warm light shade 2 acrylic paint, to overall spray the 2-bladed propeller. Once the acrylic base coat has cured, I used artists oil paints - actually a mixture of Burnt Sienna, Yellow Ochre and Raw Umber in a ratio of 25% to 25% to 50% - to simulate the wood grain and spread a thick layer of paint around. At this point the oils will be workable for several hours. Then, while using a clean & completely dry broad, hard brush, I dragged it over the oil paint, leaving wood grain streaks. As the brush picked up the paint, I wiped it off on a clean, lint free cloth. I left it alone to dry for 24 hours. A day later, while oil paint was not fully dry, I used a clean soft brush to blend the streaks, just a little more. As soon as it looked OK to me, I left it few days more to dry completely and then spray it with Tamiya Color X-24 Clear Yellow acrylic, because it also helps bring the grain color out more. The 2-bladed “wooden” propeller placed on the front end of the (previously installed) transmission block. So, this is how the assembled block of 7-cylinder radial engine, transmission unit, drive shaft & cooling fan should look like when correctly fit into each other.
  15. The engine’s cooling fan, proved to be the most controversial part of the kit. What really happened? Well, first things first: The Kolibri helicopter was equipped with an air-cooled 7-cylinders radial engine located inside the fuselage center-section and enclosed by outer skin. The powerplant should be efficiently cooled somehow to ensure proper & continuous operation. To do so, air was drawn in through openings beneath the fuselage by a wooden cooling fan with direct drive from powerplant provided strong air flow towards engine’s cylinders. Despite the fact that “Luftwaffe Profile Series #6 Flettner Fl 282” ISBN 0-88740-921-0 book (released on 1996 by Schiffer Publishing, written by Theodor Muhr and originally publilshed on 1991 by Flugzeug Publikations GmbH under the title “Flugzeug Profile Flettner Fl 282 Kolibri Varianten”) says that “…continuous cooling provided by an eight-blade wooden cooling fan with direct drive from the engine…” (page #8), I could not find any front head view photograph of the so-called 8-bladed cooling fan. On the other hand, Ryszard Witkowski author of the “Rotorcraft of 3rd Reich #5109” ISBN 978-83-89450-43-2 book (released on 2006 by MMP - Mushroom Model Publications), says that “…the engine was cooled by a wooden twelve-blade fan…” (page #24), which further complicates the question on the cooling fan issue. So, what type of cooling fan was actually fitted in front of the air-cooled 7-cylinders radial engine? Was it a 8-bladed wooden propeller or a 12-bladed? Or maybe none of the above? To make things worst, the available diagrams are side-viewed and it’s not easy to say if the cooling fan is 2-bladed, 10-bladed or 50-bladed. IMHO, when it comes to “cooling” issue, I think that a multi-bladed fan would be more appropriate. Although a 6-bladed cooling fan had already been used on Flettner Fl-265 helicopter, the Deutsches Museum officials deny the 8-bladed or 12-bladed fan claim and they strongly support the 2-bladed propeller 90 cm Ø version - after all, they supposed to know better about Flettner 282, don’t they? Furthermore, I spotted more errors and incorrect assumptions into the pages of the aforementioned books, which further strengthens my doubts about the accuracy of the given information. For example, it is written that Flettner 282 had not functional elevators and they were just “dummy” horizontal stabilizers bolted to fuselage frame, which is a huge mistake because blueprints, actual pictures & videos show the exact opposite. Also, it is written that all Kolibris from V20 to V24 versions were completed as two-seaters, which is also a false claim, according to Luftwaffe’s WWII and Anton Flettner Flugzeugbau GmbH files. Anyway, since I had not a clear evidence of an 8-bladed or a 12-bladed wooden propeller use on Kolibri helicopter and having in mind that both above mentioned books had already few mistakes written into pages, the multi-bladed wooden propeller story seems a little “questionable” and the 2-bladed cooling fan version is considered as the most “plausible”, just like appeared on the Focke Wulf FW-61 helicopter which already had a single 2-bladed propeller for engine air cooling. I hope my estimations / guesswork are correct and I will not have to publicly perform seppuku because of shame.
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