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Simon Chaddock

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Simon Chaddock last won the day on May 13 2023

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  1. With the nose built on it is starting to look like a XF108 Rapier. Still got to squeeze in all the RC stuff in the nose.
  2. At long last a full power test of the QX 40 mm 12 blade EDFs. https://www.youtube.com/watch?v=TbHSBI8VHPA On a 4s it is drawing 36A giving 511W. This is far more than it will ever need as the FX108 only weighs just over a pound ready to go! It does shut the door smartly though! The EDFs are beautifully balanced and can run at very low RPM.
  3. shepeiro Note you donor aircraft has broad chord wings. Model aerodynamics suggest that below a certain chord the skin friction of air becomes a major factor. In other words as an aerofoil its lift to drag ratio rapidly falls away. My own experience suggests a chord below 2" (50 mm) is likely to be more "decorative" than "efficient". The DH planes of the period quite reasonably used relatively high aspect ratio tapered wings that are good for both aerodynamics and structural efficiency but then the minimum chord was measured in feet not inches! Just an observation but you may find that at such a small scale the performance and handling of your DH based planes may not match that of the apparently "crude" wing of the donor. Will follow with interest. Keep posting.
  4. Just a point but you can class balsa as a foam. It is certainly not a true solid but is a cellulose structure around lots of air pockets. Makes it light and quite rigid for its weight. Now Lignum Vitae is also a cellulose structure but is virtually a solid. It is so heavy it does not even float but it does make good lawn green bowling balls! "Foaming" as a process can take many forms.
  5. There is nothi8ng wrong with using the servo as a structural member in a foam wing. It is actually much stronger than the foam! I do it all the time particularly on a thin foam wing. Cut a servo sized hole and glue it in. The servo will be more securely restrained than by any other method. There is a servo under there! The foam wing is 7mm thick at that point. The servo is 8mm thick so protrudes 1mm from the underside. It will be hardly noticeable when painted. The servo is absolutely rigid but if required can be cut out to be replaced.
  6. Nothing very spectacular for me just the "flapped" FX707 Albatross converted chuck glider. First flight for me for a full 2 months and not quite as calm as it looked with some quite strong gusts in the otherwise gentle southerly which made slow flying rather tricky.. No damage apart from some mud on landing. What I did not expect was so much of the field to be flooded. Even the bits that were not under water were very "squelchy" so the actual operating area was much reduced.
  7. Hi shepeiro My concern with such a small out runner in your 5 cylinder would be that almost any added weight (and drag) might become an issue although I do agree many single engine radial engine types are likely to need nose weight. However if it is required it does raise raise the power requirements for the plane to fly adequately. My 9 cylinder is fitted to an all foam Antonov AN-2. As you correctly surmise it was always going to need additional nose weight so a printed scale 9 cylinder ASh-62 was not a problem although the crankcase still had to be big enough to house a brushless that could adequately turn the scale 9x6 four blade prop. As it turned out despite the light foam airframe even a printed scale engine mounting and cowling could be included. The only problem is it is all the detail is completely hidden so it became more an exercise in developing the required printing techniques to actually print it. The only way was to break it down into individual components (over 58) and glue them together like a plastic kit! Little is visible but at least I know the detail is there inside!
  8. Hi and welcome That's very neat It would be interesting to know the weight of the printed 5 cylinder compared to the tiny out runner inside the crankcase. Of course the crank case is relatively bigger on a 9 cylinder.😉
  9. I suspect it very much depends on the weight of the EDF and what foam it is made off. All my EDFs are hand launch and grass belly land. They are made of various thicknesses of XPS foam and are painted with water based acrylic paint. They are by most standards very light so the landing speeds are low. As a result underside damage is not a serious issue and can be easily touched up if required. The underside of my 3 year old Sea Hawk made from 5mm XPS sheet. Apart from the acrylic paint it has been sprayed with acrylic clear lacquer that allows any dirt to be wiped off with a damp cloth. https://www.youtube.com/watch?v=NgYjJjTJLEw&t=29s Rare for me I actually had an audience for that flight!
  10. Some progress. The wing tips, control surfaces and elevon servos added. I cannot go any further until the servo extension wires and the Little Bee ESCs arrive. Only when they are installed can the nose section be added and some idea reached as to where the battery needs to go. As the EDFS are "right at the back" the LiPo position will be the only available "balancing" item!
  11. Did you note the height the package was dropped from! Anything fragile would have to be very well protected or perhaps identified that it could not be delivered that way. Hard to see any real benefit of drone delivery trial other than to identify what it would not be good for.
  12. What you have to remember is the actual loads a rib has to take and the extent full size go to keep weight down. Note the construction of the Tiger Moth ribs compared to that of the spars! Unfortunately scale strength effects rule out taking conventional materials down to such sizes. You really need to use something different. 3D printed ribs has possibilities with advantage the outer profile is very accurate.
  13. I would agree with Frank. Electric power is probably the best way to emulate a scale turbo prop and produce a plane of a realistic size and cost but an IL-38 would definitely not be a beginners model. This shows an electric powered scale turbo prop. A scale nacelle and a scale diameter prop. Not only is the motor within the nacelle but the speed controller and the LiPo flight battery s too!
  14. shepeiro I video quite a number of my flights using a tiny camera fixed to a base ball type hat. The videos are of limited quality and even with a ring sight it is hard to keep the plane in view. The videos are primarily for my own benefit to provide a record of what actually happened. Some of the "better" ones are downloaded to You Tube so can be added to web sites like this. Amazingly there are over 600 such videos although not all are of plane "inflight" but the majority are.
  15. As suggested you may be expecting too much from simply applying washout. For instance are you absolutely sure your previous "tip stall" incident was not due to a defect in the wing? Even motor torque can promote a tip stall if power is applied at the wrong moment but it is rarely considered "pilot error" which of course it is. Many wing configurations do not display a "tip stall" as such just a conventional wing stall. What I an trying to point out that a tip stall can be caused by several things so unless you can visibly see something wrong with the original wing relying on washout to eliminate "tip stalls" on a new one may not have the expected result.
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