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Rizon

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About Rizon

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  1. Next up I completed the assembly of the horizontal stabilisers. Having decided to go for foldable wings, I also wanted to have these moveable. To prevent them from just flopping around, I made a simple friction lock. For this I cut three sections of plastic tubing and glued the smallest one on a 1 mm aluminium rod. Then added a small spring followed by the part that gets bonded to the fuselage, in other words it is only sliding on the shaft. The last and longest part is again bonded to the aluminium shaft in a way that the spring is compressed. The normal force then exerted between the interface gives enough friction to lock the flying surface into an arbitrary positon. The stabilisers them selves are from two 0.5 mm sheets that are bonded only on the perimeter, and the torque tube forms the main spar to complete the thin walled structure. Now I only have to install the stabilisers…. R
  2. Hold your horses! I'm still getting to that part! But since you insist: I'm thinking along the lines of "Have Glass" grey, or similar to what the F-35 wear. Gives a nice middle way between the All Black and Naval grey tones. Lets assume that the latter developments in paint technology have been applied to the F-117 in the mean time. So lets say this is a late service F-117N As to the decals - I plan on using the kit decals, as they are in the more or less appropriate light grey to give the right contrast. As for the squadron markings - still up in the air, as I still need to check how they used the squadron colours previously.... R
  3. I used a stock standard Ender 3, with a 0.35 mm nozzle. Those wheels are the limit of what the printer can do with the nozzle, but I did design the part's details with that nozzle in mind. Was the first time I 3D printed, so all in all, not bad for the first attempt, I think
  4. The past week or so have been spent on cleaning up the model by closing, filling or covering holes, seams or joints that stem from the conversion. That is effectively done now, such that I can now proceed with adding smaller details and the last set of assemblies. And then gave it a quick and light dusting with Tamiya white primer, just to check the effectiveness of my patching work. Surprisingly most of it turned out good. Though here and there some small amount of re-work is required, but that can be completed with the remainder of work to be done. R
  5. A blob of house-hold silicon for a half mould (takes 2 to 3 days to cure though) and epoxy glue as casting material. Nothing special about the materials. Play Doh may also work for the mould, but I have not tried that yet.
  6. That thought has crossed my mind! However, at the moment I am more considering an Intruder Squadron. When the A-6 was retired, Lockheed would have the F-117N ready (approximately). And being more of a "Bomb Truck", I think an attack Squadron would be more appropriate. And one of the last A-6 Sqadrons were the "Nighthawks"..... Just sayin.... (Also in my time-line, the F-14 would not be retired so early, so the Sundowners would still fly the F-14.....)
  7. Cool! Which kit are you using if I may ask? On the net I have stumbled upon two different conversions of the 1/144 scale Revel kit, which has the same wonky geometry. The conversions were a bit more basic than my current attempt, but very passable. Then I also once found a 1/72 F-117N that was built as a paper model.
  8. The canopy of the original kit is one of those horrendous areas when compared to the actual F-117. The Naval version was proposed with a frameless canopy, so I shaped a plug from balsa for vacu-forming. In the process I also tried to correct the sweep-back of the kit’s front cockpit section. The plug was coated with cyanoacrylate, carefully sanded down, added another layer, sanded, another layer, sanded and polished. Made a nice smooth master for the vacu-forming process. And as you can see, it took two tries to make a decent plug. [/url] I prefer to glue shin strips of styrene along the edges of vacu-formed canopies; in that way the cyno does not fog the canopy, or can easily be removed. Then when gluing the canopy on, I can use regular styrene glue and not run the risk of fogging. One of the modifications Lockheed proposed on this variant was a bigger bomb bay resulting from a deeper fuselage. For this, I built a “canoe” that was then simply glued to the otherwise flat fuselage bottom. Note the sensor window at the leading edge of the “canoe”, a feature that appears on some of the released concept sketches. The landing gear was supposed to be similar to that of the F-14. Not having any spares around, I constructed the rear from tubing and sheet plastic to somewhat represent the F-14 like landing gear. The wheels were 3D printed; seen here with a layer of white primer already applied to check for surface details.
  9. I am not certain if there was conflict of interest between these two - from the timeline (being the early 1990's) it could have been. Just read somewhere that the Pentagon severely reprimanded Lockheed after trying to sell the 1st generation Stealth Fighter to them while also expecting sales of the F-22 at the same time.
  10. This is quite a big aircraft actually, so I decided to also try incorporate a working wing fold mechanism. This is what I ended up with after a few prototypes. While at it, I also built hinges for the inboard flaps. Once the hinges and flaps were installed, along with a main spar and leading edge spar, the top surface of the wing was added. The top surface is also a 0.5 mm thick sheet, so the entire structure of the wing is effectively a thin walled structure. I made rudimentary intake ducts from a paper-thin plastic sheet. For this I started by drawing the ducts in CAD and plotting out the developments. Then the shapes were cut from the plastic sheet, folded/rolled into shape, and finally installed.
  11. The F-117N was a concept by the Skunk Works to sell a stealth fighter to the US Navy. The Navy however found the concept unsuitable. But when Reading Ben Rich’s autobiography, one has to wonder if it did not have more to do with the Pentagon Politics that resulted in Kelly Johnson's unwritten 15th law. I had this Revel F-117A lying around – the original release of the angled aircraft that was based on an interpretation of the first image released of the Stealth fighter. That kit is woefully inaccurate, basically being a bit “squashed” in the longitudinal direction and a few incorrect details. I was always wondering what I should do with that kit. Turning it into the Have Blue prototype is not realistically feasible, but one day I again stumbled upon the proposed naval version Lockheed proposed… Now there was a grain of an idea, as the different wings would possibly hide the incorrect sweep of the kit and re-working the tail end would also cover most of the other inaccuracies. To see if this idea could work, I took a photo of the kit fuselage and overlaid a “highly accurate” blueprint I got of the internet and found that the conversion is quite feasible – even being reasonably to scale in 1/72. Most of the dominating features were in the correct place, and the rest could be chopped or beaten into place. I am not attempting to make this model completely accurate, as the real thing was never built, there is no direct references available. Only the evolving concept drawings that were released. So a bit of artistic engineering interpretations will be used where appropriate. End of last year, as we were preparing for the December summer holidays (I’m far south of the Sahara), I was contemplating what to build. As we usually spend the holidays on the in-law’s farm, the constraint I had to consider was it needed to be a project I could travel with. The initial stages of the conversion don’t involve fine detail, so it fit the bill. And I was keen for some plastic surgery / butchery. First off marked the areas for trimming or correction. Eventually decided to leave the fuselage leading edge sweep as is. The tail end was cut off and repositioned further aft. While some panels on the top fuselage were corrected. All things white of course indicate modifications. And subsequently the first parts for the main wings and stabs were cut and assembled. Apologies for the quality of the pictures – my work desk on the farm was a patio table that got moved around, depending on the requirements for sun, shelter from the sun, or shelter from thunderstorms.
  12. Perhaps pearlescent acrylic paint will work in 1/72, most art shops I frequent have some or other variant that can be painted / sprayed over any previous acrylic colour. Some of them have very fine "flakes", or what ever it is that gives it the luster. Always wanted to give that a try.
  13. In days gone by, when I was doing post-graduate studies and my best mate was building hours for his Com license, I was the preferred extra weight for cross country navs ( I knew about flying a bit, something of nav, but more importantly was single and could work flexi hours, so no one to nagg when am I going to be home etc...). Most of the nav sorties we flew at night, in those beautifull summer or winter nights the Cape of Storms (Soutn Africa) can give. Our plane of choice: Piper Tomohawk. So, taxying out one evening in Cape Town International a BA 747 ends up behind us on the taxiway. We get take off clearance and as we rotate the 747 gets clearance to line up and depart. With a strong warning (advice) from the tower to watch out for wake turbulence from that departing Tomohawk.... Cool, calm and collected read-back as ever from the BA captain "copy cleared for take off, alpha departure, caution Papa Charlie wake turbulence, thank you and good night"
  14. Recently I had a chat with a F-35 test pilot, the guy who gave the first non-US demo at Fairford a few years back. Apparently when being strapped into an F-35 you wont know if you are in the A, B or C model, unless you twist your head to the 6 o'clock position and try to figure out if the lift fan is installed or if longer / folding wings are there. They all fly the same and Billie himself often does fly all 3 variants in the same day and there is hardly ever a need to conciously take note of which one you fly. That is ynless you fly VTOL or carrier ops ofcourse.... R
  15. If I may ad my 2c worth of putting things to focus.... I have been involved in more than one reverse engineering effort of an aircraft, which involved everything from pen and ruler measurement to top end photogammetry and LIDAR. And it is not a trivial whizz bang process to get the geometry right. My particular case was to engineer a wind tunnel model, so aerodynamic accuracy was CRITICAL to say the least. As wonderful as LIDAR is, it gives you a point cloud, ie a collection of points in XYZ space. Now this information has to be processed to turn it into a surface ( like a NURBS surface, STL wont do) and that in turn into a "solid model" that CAD can understand for further processing into useable components. The fitting of these surfaces is difficult to say the least. Even as LIDAR gives you millions of data points to work with, acurate fitting is still the focus of much, much research in reverse engineering circles. Especially in areas whrere the rate of curvature (like at the leading edge of the wing) is high, do the biggest errors creep in. Then there is also the rendering of the CAD model. As simple screenshot from a CAD program does not convey the true geometry in my experience. It depends entirely on the graphics processing, and other things like screen resolution etc. One will have to "play" with the model interactively to get an idea and actually do further measurements on the CAD model to understand the geometry. And even further there is the fact that something will have to be manufactured in 1/72 scale and injection moulded with preferably only two mould halves. On said wind tunnel model the thing had to be machined from marraging steel and selected parts 3D printed in titanium - all at the large scale of 1/12.5. The approximations that one has to do even at that scale caused many heated debates - with valid reasons all around. So now try to do that a 1/72 and keep everyone happy (dare I say every arm chair modeller...?) I for one applaud Airfix's efforts. I hope the guys there have fun. I certainly did, even though years later I still dream of data points and the Hawk geometry....
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