Some further investigation into flying options were discussed with the Croydon guys this morning atop the cold and blustery flying site just to the west of Biggin Hill. The consensus is that this Extra is just too weighty by a few ounces to be flown legally at the Fickleshole site. As several members are also members of the neighboring Caterham club, the view was that I should also attempt to join that club when a vacancy arises. One member of the Croydon club has a very large Lysander scale model which tips the scales at over 11Kg and one of the reasons he joined the Caterham club was to be allowed to fly that model in the appropriate and legally designated airspace. So all is by no means lost as regards the future of the Extra. That is a big relief.
A little more work has been done to ensure the legal requirements and safety of this model in flight. The stipulation in the Bristish Model Flying Association handbook demands that fail safe mechanisms are built into the model to ensure motor idle or complete close down are possible at any time during the flight. The stipulation is that the mandatory minimum equipment and programming of the control system forces a motor down to idle or complete shut down if transmitter signal failure were to occur. That I have achieved and I also have an additional transmitter switch dedicated to cutting ignition power completely if required for some reason. Frustratingly, my transmitter is slightly aged in internal circuitry design and the fail safe facility is only present on the Channel 3 throttle circuit servo operation. Whilst that is sufficient to conform to the minimum requirements, it does not also facilitate ignition killing which would be an added security bonus in the event of complete transmission failure. Fortunately, transmitter failure is very rare unless one is stupid enough to fly with nearly discharged transmitter batteries. As a model pilot, it is ones responsibility to ensure that one makes every effort to ensure safety by voltage checking all battery packs before flying by way of pre-flight checks. The pre-flight procedures are little different to that involved with flying a full sized aircraft. Safety is paramount.
Sensible model pilots also try to raise their skills to recognized levels. This year I shall be aiming towards the basic proficiency A license and perhaps also the slightly more advanced B license. One is examined for proficiency in flying control of a model. The A license is essentially the ability to demonstrate safe model operation and the ability to take off and return a model to the landing strip without incident. That also includes the ability to fly a square cornered left or right hand landing circuit and perform an aborted landing. Some oral theory is also part of the test. The more advanced B test includes the ability to fly positive and negative G aerobatic maneuvers in a formal sequence as well as an emergency landing without engine power and a recovery from a flat spin with a totally stalled entry. So I have some challenges ahead.
I`m hoping the smaller 60" Ultra Stick will prove a suitable air-frame for these tests. It is the smaller of the two models in this image. The larger model is an identical design scratch built and enlarged by myself. That has an 80" wingspan but is rather heavier than the smaller original 60" version in the foreground. It may well be that I also build a second air-frame but this time with an internal combustion glow motor bolted to the front bulkhead as an alternative to electric power. I have a used 17cc two stroke glow motor in a box which needs a home and will fit the somewhat slender small Ultra Stick fuselage. It will certainly be rather faster than the electric version I already have. Electric models have shorter flight times due to battery size dictating short flight times of only around five to seven minutes. It is not unknown for pilots flying electric models undertaking A or B tests to have to make a landing part way through the test just to change batteries. That is obviously irksome and inconvenient. It perhaps makes better sense to use an I/C model in tests to get longer air times and avoid breaking up ones flying routine due to a lack of battery capacity.
It seems strange not working on the Extra which has become part of my life for around the last couple of months. The conservatory has had a good sweep and clean out. My usual working chaos has been reduced and just for once I have a chance to clear my head and mentally relax. It is surprising how much mental effort is required for this hobby. It is little different from working on full sized machinery but thankfully there is rather less compliance paperwork to be administered.
Better to have ones own meter than to have to beg a club member to be present at a certain time and place with the official meter on perhaps multiple occasions. It will be interesting to see whether my meter and the club meter agree average readings.
Joy of Joy. Just Engines are starting the exhaust system build today. The spec and £220 cost has been agreed. Dispatch should be in a couple of weeks.
Something perhaps to look forward to in the Summer. The BMFA have a large model flying site at Buckminster near Grantham. OK, it is a 143 mile trip to get there. I envisage an over-night stay in a hotel with flying on two days. The Buckminster site is set in 40 acres of open, flat farm land and has an over 20Kg model classification. Fees are just £8 per day but one has to possess a B-license before using the site. That is something I shall be aiming towards this year. My Fathers, cousins, husband (what does that make him?) visited yesterday and he takes a keen interest in my model builds. He is a great fellow and I get on with him extremely well. The suggestion is that we later arrange a two day or more jaunt up to Lincolnshire and fly the heck out of my models on that very open site. Dave would be a delight to have with me. I`ve not had a holiday away for years and subject to my next lumbar operation being helpful, a nice little trip away flying my kites seems like an idea.
Rather than shell out for a second fuselage from the makers at nearly £100, or buying a complete second kit for £216, the economical answer lays in self building a second fuselage myself. I have some micro plywood in stock and a pile of balsa scraps left over from other projects. A suitable undercarriage has been found, a tail wheel unit and various other odds and sods. I`m looking for a good, used 0.61cu in (10cc) engine with decent compression. A few suitable units are on eBay currently and I`m waiting for the auctions to come up to time...then I`ll pile in! I`ll need a bit more fluorescent red covering but have sufficient white in stock.
A good start on construction began this morning. I now have a tail-plane, elevators, rudder and fin built, hinged and covered. They look very little different from the genuine article except presently I`m short of the distinctive red covering but a roll of it should arrive shortly. With luck and careful budgeting, I should be able to get this second fuselage complete with engine, three new servos and covering done for about £100. Had I built a complete new kit, then that would probably cost around £320 to get into the air. Times is hard my boy with still more cash being needed to finally finish the finance sucking Extra! Mike
Construction has not been that easy. Two things influence the build. One is that the 2.5mm ply takes rather more time and effort to cut out than balsa wood. It is also more difficult to hold parts together when building. With balsa, you just use dress making pins to hold things together whilst glue dries. With ply, you have to screw or clamp components together which is a little tedious and is somewhat harder. A box full of various sized clamps assists the issue. The other matter is that ply tends to move around once cut. The tensions change within the sheet ply once it is cut to shape. You start with a flat piece of material but after cutting one finds the material liable to warping and distortion. The flat piece you started with curls up like a British Rail cheese sandwich! I found it necessary to screw the bottom chassis plate to a flat board during building to limit distortion whilst other components were glued into place. Even then, it is a little frustrating to find small twists occurring once the complete structure is removed from the flat building board. Miss-alignment at that point is hard to correct. One just has to accept what comes off the board and make the best of it. This construction is about 95% good and I`m reasonably happy with that. Tonight, the fuselage sits in front of the blower heater having been partially soaked in and now glistening under three coats of shiny industrial boat building epoxy resin. The epoxy is necessary on this particular model as the fuel, (a mix of synthetic oil, nitro-methane and methanol), is highly penetrative and will impregnate plywood at the slightest opportunity. One doesn`t want to suddenly find a model has gone oily and soggy under the covering and is beginning to disintegrate. The epoxy resin seals up the plywood and is worth every moment of time taken to achieve. For the sake of a pounds worth of resin and twenty minutes taken to do the job, one would be a fool to ignore this stage.
Once this fuselage is complete, I shall have one complete and original kit built model plus one extra fuselage. The kit built original wing obviously fits my scratch built fuselage. It would seem to make sense that I buy another full original kit which would enable yet another fuselage to be built perhaps with that now spare 1.08 motor. That with another wing then sourced from the kit manufacturers, would give me three fully built and operational variants of the same model. These Ultra Stick models are incredibly versatile and the kits are great value. 90% built and fully covered needing only about seen or eight hours to get to a flyable state, they are one of aero-modellings best kept value secrets. I love them to bits. Easy to fly, docile at slow speed with flaps deployed, highly aerobatic but with a sweet temperament and robust construction.
Awaited in the post and probably arriving this morning is a further roll of the spectacular florescent orange covering, a couple of lengths of 1.78mm piano wire for control push rods and some plastic 3.2mm)D sheaths in which to run the wires. The runs down the fuselage were initially drawn in on my full size paper plan and dimensions for holes in the structural formers transferred onto the ply when I cut out those parts. Great care is needed to ensure formers are dead square and accurate in height and width commensurate with their location on the chassis plate. Any "out of square" formers badly influence the overall eventual shape of the model and also the ease of build. Good dimensions are vital and accuracy has to be within about 0.5 of a millimeter otherwise you end up with a distorted structure. Bent models fly in circles!
My original idea was to power this model with a second-hand 0.61cubic inch (10cc) glow motor. A couple of weeks ago eBay proved hopeless in sourcing such a motor and small ads on the Croydon and Riddlesdown Club sites similarly produced a blank result. At that point I dragged out a 1.08cu in (17cc) motor from stock and proceeded to build that onto the model. Not ideal due to its high fuel consumption and the impossibility of installing a larger fuel tank. I ideally required a smaller motor for this model as I wanted moderate fuel consumption to enable at least ten minutes air time whilst taking A & B license flying examinations.
Having set the front bulkhead up for the 1.08 motor, eBay suddenly listed several suitable motors and one of them came to me for just £23. So out came the 1.08 again with a view to installing the .61 once it arrives. It is described as having good compression but with typical user marks and battle scars. Now I`m having to install a smaller engine mount as there is a 5mm difference in crank case dimension width between the 1.08 and the .61 units. Some trimming of a pair of stand alone nylon engine mounts looks promising and I`m hopeful that I can get these mounts to pick up on the captive mounting nuts already installed in the fuselage for the 1.08. If this works out well, it will be perfectly feasible to be able to swap between the smaller and the bigger motor just by removing four 4mm mounting bolts. At that point one can choose between moderate performance and fuel economy or something with rather more grunt but shorter range. That makes the same model again quite versatile in as much as one can quickly and easy alter the personality of the model by engine changing within five minutes even at a flying field location.
The build has progressed well to date having taken only about five days to create this fuselage from scratch. Had a pre-cut parts kit have been available, it could have been built in a day! Hacking components out of raw material, is slow and time consuming. Good progress has been made so far and there isn`t a massive amount now to do to get this fuselage finished. It needs the control push rods installed, requires covering in heat sensitive covering material, the fin and tail plane fitted, motor installed and a push rod fitted back to a servo for throttle control. A landing gear has been cobbled up from the scrap bin and is of similar proportions to the gear to be found on the original model. I`ll have to look out for a nice pair of wheel spats to fit the reproduction gear. Spats suit this model well.....something will turn up on eBay. Finally, a couple of images of the original and my scratch model showing internal details. Mike
The other evening I hit eBay again for another identical Irvine 0.61 which was described as having good compression. In their time, these motors were always highly regarded. The motor arrived and to my annoyance had little more compression than my auction bought unit. The seller refunded the money immediately and was full of apologies. He decided that the motor wasn`t worth returning to him and so I now have two clapped out units! The auction motor sits in a box in pieces awaiting its fate. Hopefully, the piston ring producer man can provide replacement piston rings in which case I`m hopefully laughing. I`ll wait for a response before deciding how to further progress.
Buying a motor at a distance without examination is a dodgy business. Many sellers are rather non committal or reluctant when it comes to giving a truthful description. As a buyer, one hopes to weed out the blaggers. "I`m selling this motor on behalf of my Granny, I don`t know anything about these engines so please don`t ask me any questions about it". That doesn`t inspire confidence.
You really need to find almost brand new and up to date engines and avoid the cheap old vintage smokers. It isn`t an easy game. It is perhaps better to push up you budget and stay away for the old bangers. In many respects, it is like buying an old car. Buyer beware applies. You can`t expect much for £25 but £50 spent in this case should find a half decent example. The problem when it comes to buying is that there are many guys out in the market place all looking for decent motors and they are so keen that they get carried away as the auction finishes and can be prepared to almost bid up to price of a brand new, boxed and unopened example at full retail cost. £82 buys a brand new Chinese ASP 0.61. I simply refuse to pay much more than about £40 for an example that is no longer "new". Good examples are usually easy to spot and attract high prices. May be I also have to lift my budget somewhat and stop grubbing around in the old clanker market! We will see what Monday brings with the piston ring maker. May be my two old Irvine units can be got back to life at a reasonable price. The perils of second hand bargains!
So this clone build is now almost complete. Just a decent motor and a radio receiver remain to be fitted and it is ready for flight. Total cost with two new servos and one older one fitted together with other parts materials required, probably about £80. A comparative new original fuselage would have cost around £220 to get going. Here is the original set up for the electric model. Note it does not hae a third throttle servo. In its system, an electronic speed controller takes the place of a mechanical servo. What is next on my production line? Some of you will remember the red Fokker Tri-plane constructed last November. The makers were apparently impressed with the build after seeing images sent to the supplier, George Worley at 4-Max in Basingstoke. As a result, the Chinese manufacturer, Dancing Wings sent me free of charge, one of their first production kits of the Second World War, Fiesler Storch. The Storch was used as a short take off and landing (STOL) artillery reconnaissance spotter aircraft by the Germans. It was also the type of aircraft used to snatch the imprisoned Mussolini from a hotel atop a mountain in a daring smash and grab raid. Montgomery also used a captured example for flying around Europe after D-day. So I now have a basic "short" kit here and the build will begin shortly. The wingspan is 63" and finished weight should be less than 3Kg. Colour scheme is likely to be as a Swiss registered aircraft rather than a military camouflaged example. The Swiss example is depicted in this image as a taster for things to come.
The Extra received a good welcome at the Croydon Model Flying Club on Thursday night. It is a weighty model coming in at around 16Kg. It is said that it will fly in a similar manner to the full sized aircraft but is unlikely to be able to hang on its propeller due to bulk. The latest modern examples are appreciably lighter with much of the structure being made from carbon fibre. By comparison, my Extra is from a kit that is some 25 years vintage and rather heavier as modern technology was not in existence when the model was produced. Time marches as does design. This model will be what it is, not what it is not or it might like to be! That can never happen.
The Fiesler Storch build has started. A typical Dancing Wings production in the same style of construction as the recently finished Fokker Tri-plane. The first Storch components built were the tail plane, elevators, rudder and fin. I immediately noted exceptionally slender materials primarily designed to save weight at the tail end of the model. Like the Tri-plane, the size and application of this construction caused me some angst. The balsa framework is small and very fragile and in my opinion insufficiently robust for general use. I consider the above parts are liable to twist, distort, bend or even break under load rather like a scaffold plank set on two tressels with a heavy man jumping up and down in the middle. The sensible and logical engineering application would to be to make the timber sections deeper than they are wide. Wing main spars are usually of I-beam construction and resist deformation when loaded. Sadly the makers do not seem to understand these basic principles. Will DW ever learn? Mnnn....Controversial and loaded with curios these kits certainly are. I have a love/hate relationship with them.
Having constructed the elevators, the soft and totally inadequate elevator leading edge spar broke as I picked it off the table. Not a good start. I repaired that break with epoxy, further reinforcing the area with micro-ply and more quick set epoxy together with a typical piano wire stable type joiner to link and securely join both elevator halves. Continuing to be generally un-happy with those components which could probably have been designed by Mr Whippy, I sheathed the entire batch of parts with 1/16" balsa sheet punctuated in selected places with lightening holes. More lightening is envisage before covering takes place. Obviously the thickness of the components has risen in depth to some 8mm instead of a weedy and totally structurally unsound 5mm. I don`t mind pranging a model myself but object most strongly to manufacturer induced structural failure. My reinforcement inevitably comes with a slight additional weight penalty. Similar major issues appeared on the Tri-plane and needed brace supports to help the situation. I had predicted this issue immediately I learned that the makers of the Tri-plane were sending me a Storch kit for evaluation.
Whilst I appreciate there is some structural stiffening gained when covering is applied, I considered that this would be again be inadequate for the intended purpose...namely flying from rough flying sites not to mention physical damage cause in transport or when transferring the model from workshop to car. An acceptable amount of reserve strength must be built into any model to allow for a hard flying life and general knocking about when handled. The supplier George, when told of this repeat issue obviously advised I keep any additional modifications at the rear of the air-frame to the lightest possible weight. I don`t think he was too pleased to hear I was again having slight issues with a DW kit. From my perspective, I`ll not fly any air-frame which I consider to be un-airworthy and perhaps puts property or peoples lives in jeopardy. To do so would and could be seen as negligence should the worst occur. Most problems can usually be solved by rational thinking. Anything is fixable given the right application. My task is to ensure that happens but without adding un-necessary weight to the tail of this model.
The fuselage has also been started and there the situation is a much happier state of affairs. No issues there so far. Of interest is the use of square section hollow carbon fibre "tube" with sides of approximately 4mm. It is quite amazing that this material can be produced in such small sizes. Strong and light, it features as stringers in the rear of the fuselage and can be seen in this image. The fuselage reminds me of an ugly old horse about to gain wings. An odder aircraft you couldn`t hope to find.
It appears that the model engine piston ring maker I contacted via eBay recently, can make me two new piston rings for the clapped out Irvine .61 engines I have. If successful, fitting new rings to both motors might get these units up and running again. Lead time is about two weeks. So that is were we are tonight. A bit frustrated but moving slowly forward.
Here the partially covered fuselage has had the wing joiners fitted. That went well after a bit of faffing about. Various sections of 8 and 10mm round carbon fibre wing spars being added during this part of the construction. Instructions were obtuse in the build manual which mean I almost had to reverse engineer the problem to see where the designers mind set had originated. This model is like building a large jigsaw puzzle but with half the illustration missing.
The cockpit glazing took five difficult hours. Pre-cut and drilled celluloid sheet is supplied with matching drillings being found on the cockpit sides. Wonderful until you discover the holes for fixing screws are over large for the screws....out with thick super-glue and a very light touch on the screw driver. How many screws you ask? I can tell you. Two hundred and sixty five of the things. A nightmare to fit. For every screw fitted by picking up with long nosed pliers, dipping in super-glue and tightening, two screws would end up on the floor. They are incredibly small and I have huge sausage fingers. How I wished my grand-daughter had been here to deal with this tedious screw fitting session. Only one spare screw remained come the finish....and that was after sweeping the floor half a dozen times to round up the ones that had got away. The finished cockpit area is far from scale in appearance and is a million miles away from helping beautify this model. The full size aircraft has non of the screw type fixings, just slender ali tube frames and glass. The appearance rather wrecks what would have made a nice, delicate model. To my eye, it looks like across between a Victorian railway bridge, the hull plating and rivets on the Titanic and David Randalls`armored lunch box. Perhaps some grey paint on those screws will dumb down the dalek like impression that is currently to be seen. I`m sure no one will disagree....it is nothing short of incredibly ugly!!
One has to remember that this model came to me as a freeby from the makers. My brief is to let them know my findings at the conclusion. The brief also suggests I should build as closely as possible to their original ideas. I`m finding that increasingly difficult as I have to make this model airworthy, reasonably robust and able to stand a fair chance of survival. Model flying is full of thrills and spills and models have a very hard life. Getting an early series model to a reasonable state is trying to say the least. OK, the kit may have been free but I still have to personally invest a couple of hundred pounds in the control and propulsion system, coverings and numerous extra parts not to mention about two hundred hours of my time in the building. The hope is that this model won`t just fly, but will be well mannered and pleasurable in operation rather than be a prize horror.
For interest, video links below this text show the full size aircraft that this model will be based upon. I`ve changed from a yellow yellow colour scheme to grey for two reasons. One is that I have a roll of very nice grey covering and a can of matching grey spray paint left over from the Extra build. It seems sensible to use up those materials rather than have to fork out for alternative supplies.The other reason for my change of mind is that the grey is very military and a full size grey example in the video is indeed flying in the UK. Markings are relatively simple and only a few letter and numeric self adhesive decals are needed to complete the model to an acceptable scale like appearance. Note how slowly this aircraft flies and its rate of climb.One of the very first STOL aircraft in existence and an ideal observation platform. No wonder these aircraft were used by both Rommel and Montgomery during the war. It is interesting to note that historically, the French company Moraine Saunier also built these aircraft, before, during and after the Second World War. They differ only in minor aspects such as a top opening cabin door, different engine, etc. French examples are known as a Cricket rather than as the Storch which is the name the Germans gave to it.
https://www.google.com/url?sa=i&rct=j&q ... 4735194771
The building battle continues. More details shortly. Looks like the site is having a triple head fit tonight. Images repeated three times.Sorry!
30 years ago I spent a fortnight building WOT plane which was a low wing aerobatic model and it flew perfectly for about 10 minutes until I had a transmitter failure and watched my pride and joy explode on impact. Being the classic giver-upper that I am I never went back to it. Your article brought it back - well done and well written
I too appreciate the fill in......I am waiting for the delivery of your customized silencer and the next installment of your big build. You are better value than a magazine subscription!
My memories of building model aircraft consists of balsa wood, paper and dope, sore and cut fingers, and driving the neighbours mad by testing my clapped out engines in the shed!
It is nice to see so many people continuing to watch this thread. Each time I post a further installment of this "Mike Models", it gets around two hundred and fifty to three hundred viewings. Quite remarkable that it appears so well subscribed as it has absolutely nothing to do with our joint interest in Jaguar vehicles. Maybe we should re-title the thread as something like "The Model Making Archers". Tune in at 7pm for another exciting, action packed episode of wizard prangs from the top of the Surrey Hills!
This thread will become a year old on the 8th February 2019. I never expected it to be so popular. Incredible that on that anniversary date it will probably have received over 15,500 hits over the preceding period. OK, I`ve been in and out of the post many times editing and posting additional material....so that probably accounts for at least 400 "hits". Thanks to everyone who regularly visits and to those who input into the thread. Whilst such interest continues to being shown, I`ll continue to record happenings as they occur. It makes a nice little documentary record of my struggle to reach for the sky. There are other rather older threads on this site which greatly exceed the number of hits on this thread but they are frequently many years older and have had the time to gather the hit numbers. I recently noted we have one thread which has over 30,000 viewings but that it was created nearly ten years ago. It is quite remarkable that this model thread has seen so much attention in such a short space of time and that it is not even remotely Jaguar related.
Dope, tissue, nylon etc have almost disappeared from the scene now. The iron on, self adhesive plastic coverings have become the norm for model finishing. Its a lot less smelly, messy and toxic. The iron on plastic film is user friendly and offends no one during application. Rather different from nitro-cellulose dope and acetone which is highly solvented and can be absorbed into the body by contact and inhalation. It isn`t good for the liver although you can finish a job on one hell of a high!!
I too remember running up glow plug engines in the garden when I was a boy. The neighbors wouldn`t stand for that nowadays. I wouldn`t blame them for complaining. These small engines sound like a chain saw and we all know how irritating they can be if badly silenced. So social responsibility now comes into play. Rod asks about the muffler for the big Extra. A phone call to Just Engines confirms construction has been started and is expected to be complete towards the middle of this coming week. No rush, the weather is cold and snow lays on the ground. Presently, it is not ideal flying weather at all. The delay allows me a bit more time to accumulate the necessary funds for the parts. It is true to say that the Extra has bled my slender wallet considerably. The Extra is twice the size of most common models and at least five times the cost. It has set me back about £800! Be that as it may, I have to get one of the local model clubs with a large flying site and appropriate designated airspace above it to agree to this over 7Kg model being flown at their site. My old club, Riddlesdown, which operate to the south of Edenbridge, presently seem to offer the best chance.
Nearer to me is Caterham club but membership is currently full so that opportunity has had to be sidelined until a vacancy occurs. I`m told there are eight people ahead of me on the waiting list so it will be a while until I can join that club. Then there is the matter of finding the right model pilot with sufficient appropriate flying experience to take responsibility for test flying and commissioning this over-sized model. The Extra is a fair sized lump weighing in at something like 16Kg. That can make a hell of a mess if it were to hit something. Everything has to be right before this model can be flown and that includes getting the sound level down to or below the mandatory 82dBa limit. It is quite a project and needs special pre-flight attention and administration.
The Fiesler Storch is progressing. Not a particularly easy build as previously detailed. Latest works now include making up piano wire and hardwood push-rods to link servos to flying control surfaces. Mechanical push-rods are a vintage style method to transferring movement from an electric servo motor down the fuselage to a flying surface. Two rods are needed. One for the elevators and one for the rudder. These 8mm square hardwood rods touch and cross one another mid fuselage. They have a tendency to rattle and clank in operation. They are also relatively heavy and are rather bulky. They are not as precise in operation as a Bowden cable type installation ie an outer sheath with either a nylon of piano wire insert. I would have preferred a lighter sheath type installation but my brief by the makers asks that I try to build the model in fairly standard "as supplied" kit form. So that is what I have done.
The push-rods are now installed in the fuselage and are linked to two small, metal geared micro sized servos. Operation is adequate for the purpose. I`ll mention these little servos again for one reason. The Chinese have the market well sewn up for value for money, cheap and cheerful electronic gear at pepper corn prices. Via eBay, I have ten of these little servo motors on their way to me from China. Including post, the ten servo motors come for £16. Just £1.60 gets you a miniature servo! If I were to buy a similar item from a UK supplier, I`d be paying about £7 for each unit. Yip, I know. It does make it difficult for a high street model shop to compete and in this respect I feel a little guilty about taking the trade away from local UK businesses. Sadly, at the end of the day, the situation is price driven and I`m as bad as the next man when it comes to attempting to stretch funds as far as possible. I hang my head in shame.....
The standard kit features a flimsy tail-plane, rudder and elevators which I considered too frail for the job. The leading edge of the elevator in fact broke on me as I picked it up from the bench. The weak point was due to a part number laser burn, (T10) in which the 0 had been burnt out completely to leave a hole in its place! The material used for that particular part was of very soft grain and not what one would normally expect to be used for a torsional load carrying component. I felt it necessary to beef up those components by cross grain sheeting with additional 1mm balsa either side of the standard structure. This obviously increased weight significantly which isn`t desirable. For every one unit of weight added at the tail end of the model usually requires ten similar sized units of weight to be added to the nose to get a model to balance on the wing main spar so that the model is horizontal at the end of the build.
To counter this weight increase, I thinned down the sheeting by sanding off un-necessary thickness and then removed an excess bulk of material that really wasn`t adding anything to the benefit of the parts or indeed the situation. The end result is now a robust structure which reinforces the standard build but at only a very small additional weight penalty. When covered with the iron on film, this also adds structural rigidity and I consider these parts now fit for the purpose. They are now awaiting hinges prior to installation. You may recall I also encountered this very weak build issue on the Fokker tri-plane. This problem appears typical of the Dancing Wings product range and I shall be emphasizing my misgivings to the kit maker in my eventual evaluation report. Whether they then react to my observations is their decision. The rudder has also received similar reinforcement, lightening, installation of the sprung tail wheel followed by covering. The fuselage was covered last night and looks somewhat prettier than it did. Covering was not easy due to the very peculiar combination of profile shape. The forward end of the fuselage resembles the hull of a flying boat and must have been concocted by a fiend having a seriously bad day. Herr Fiesler, on balance was a highly talented designer and certainly knew what he was doing when he designed the full sized aircraft. Full size is one thing. Reducing to model size creates issues. However, after a couple of covering attempts, the end result is well above expectation. A trial fit of the epoxy e-glass engine cowling revealed a manufacturing defect. At one point on the cowl, the glass laminate is paper thin and stress cracks were noted in the gel coat immediately after unpacking from the kit box. I have now added extra epoxy and cloth to reinforce and restore the internal cowl structure. That done, the external gel coat cracks were V-ground out down to the epoxy cloth and back-filled with epoxy resin and low density filler powder. At one point, my grinder burr plunged through the gel coat into bare space within the cowl. A total lack of glass cloth below the gel coat was found. This poor build quality is totally unacceptable. Unless I had carried out these remedial repairs, this cowl would have continued to break up and any defects would show as marching cracks below a paint finish. Sooner or later, the hole would also have appeared due to engine vibration. Again little attention to detail and lack of quality control quality again spoils this model kit. With proper inspection procedures, these issues could have been avoided at the factory. DW needs to understand that if its product range becomes known for being shoddy, its sales will plummet. No modeller likes defective kits or components and would be usually be happy to pay a little more to get a decent kit that does not constantly kick up issues during construction. It will be interesting to see if DW are at all interested or concerned after receiving my build report. It is likely to be somewhat less than complimentary.
I see it is late in the day now but just to say the elevators and rudder are now hinged and fitted to the fuselage now. I`ll post images next time once I`ve had a chance to finish that part of the installation. Thanks again to you all for making this such a popular thread.
Apologies if the site loads images below. I`ll have to ask James to get the issue fixed.
With rudder and elevators now hinged with cyno type "paper" hinge material and slot cuts into the leading and trailing edges of the components, CA (superglue) was leached into the hinge material. I also usually drill a small hole half way along a hinge line, then trickle the glue down the hole and along the material. It hydro-scopes into gaps and sets by exclusion of oxygen. The glue is known as an "anaerobic adhesive" due to this action. It is very reliable in service but also a nuisance when you drop a few drips on the floor and then stand in it....on one occasion I nearly broke an ankle when I did just that and stuck my shoe to the floor!
So with the rudder and elevator joined to the fuselage, I spent the morning sorting out the wire and hardwood push-rods. They are bulky and clog up the rear of the fuselage. Careful routeing of the rods and precision bending of the 1.75mm wire ends was needed to get things running smoothly. Some cutting and chopping was also required and also some replacement of some of that removed material....it is very much trial and error until working correctly. Push-rod installations are nowhere near as easy to install as plastic outer sheath and inner wire set ups. As said previously, this archaic type of installation was a sop to the makers who supplied this kit free of charge to me for evaluation. Anyway, its all in now and working reasonably well via control horns installed on the rudder and elevator. Install and forget...I hope so!
I`ve moved on to the landing gear construction. This has progressed well with the odd arrangement of piano wire components all linking together. Modifications included making use of 4mm threads found on some parts. The makers suggested using eight heavy brass collets with set screws. The set screw hex inserts are often made from soft metal and it is easy to have an Allen key rip out the centre of the screw making it impossible to tighten fully which is maddening. My mods dropped the number of collets down to just two with simple plane 4mm nuts and thread lock fluid taking their place. The mod is also likely to be a few grams lighter which is always good news. Wheels are now fitted and the model is beginning to look quite promising. Interestingly, a modelling contact gained via the internet late last year gave me a call today. Rob Lewis who flies models off the beach on Hayling Island and also has numerous modelling videos on You Tube, rang for a chat. Rob built a Fokker Tri-plane from the same series DW kit which I also built in November. Rob said he had been sent a free of charge Fiesler Storch kit by the makers and that I should be envious. "Not much" I parried by reply. It caused some amusement when I also said I was also building a free Storch kit....the joke was that if you can`t sell them, you might as well give them away! When asked of my opinion, I went through the snagging sheet compiled to date. "Same as normal then" concluded Rob. "Many nightmares to come". At least two brains working on the same project makes things a little easier, but in this particular case, not by much.
Early indications suggest two three cell lipo batteries held in stock and siameesed together for capacity rather than doubling the total cell voltage, will just fit into the motor mount/battery box compartment. Space for the battery, small motor, speed controller and radio receiver tap off unit is tight. Limited airspace around the yet to be ordered motor will also be at a premium. Ventilation holes will need to be cut into the cowl for motor cooling and I note there is no through drought within the fuselage for speed controller cooling. Those matters will need addressing soon. If this model were just one quarter larger, that would have been to the good both for the power system and for physical access. My hands are large but the model is not that big within the fuselage. The wings however...well there is a lot of wing area for a very small fuselage. No bad thing in as much as the model wing area loading should be quite low and the model fly easily and slowly rather than fall out of the sky when speed is reduced.
Time now to have a mega clear up and make space for the wing building.
PS congratulations on somehow getting 15,000 views on this thread. I switch the idiot box on of a Saturday night and remark to the present Mrs R that people will obviously watch any old rubbish! Enough said!
So there we have it. 15,000 hits on this thread in just over fifty one weeks. Thanks again for your interest.
A little more done on the Storch today. Fake undercarriage oleo legs fitted and helping toward making this little model resemble a Storch rather than a flying horse. The two ailerons have been constructed. The ingenious high lift leading edge slats designed to help give the full sized or model air-frame a very high rate of climb after a very short take off or landing approach have also been made up. The slats together with trailing edge flaps enabled the full sized aircraft to operate from extremely short airstrips.
These aircraft were extensively used out of the Tier Garden Park in Berlin during the final death throes of the Third Reich. They were used to bring top controlling officers in and out of the besieged city when reporting their battle state to Hitler. The Storch really is quite a remarkable and historically significant aircraft. Only a few survive and those that come up for sale are quickly acquired by new owners.
The wing is built around a quite massive 12mm diameter carbon fibre tubular main spar below a 6mm slotted balsa upper spar. The wing ribs slide onto the carbon spar are dry fitted to the upper spar before having superglue trickled into the joints. It is quite easy to get the wing flat, straight and true just by holding the parts down on a flat building board whilst the super glue activates. A laminated two part leading edge is the glued to the front of the wing. Three further parts are glued to the trailing edges of the wing. One of those sections requires some profiling to allow the other two sections to fit with accuracy. The leading edge is then sanded to profile. Servo trays are also mounted into the wing at this stage. Six servos will be used, two for the ailerons, two for the flaps and two for the slats. Quite a complicated set up and the first wing I`ve built with this amount of control actuation. It is unusual to say the least and quite unique to have so many services operating in such a small model. This takes care and some time to get exactly right. Anything less than right, is wrong....I think the second wing panel might be a bit easier to construct than this first example. Like any methodology, practice make prefect. Once the idea is in you head, then you can make rapid progress with later renditions.
I had an interesting conversation with George at 4-Max today. George has supplied several kits, motors and power gear for my earlier models. He helps you get the specification details right first time and was instrumental in having Dancing Wings send me this Storch kit for evaluation. Essentially, I seem to have become Georges` pre-sale trial kit builder. Prior to chatting on the phone, I`d sent him similar images to the ones previously posted on this thread. Obviously the images included the problem areas of this kit as also defined above. Both of us concluded that the DW kits are under-developed and that parts quality control is lacking. Put this DW Storch kit alongside the similar offerings from Super Flying Models ie the SE5a and the Fokker DVII and the DW kit seriously plummets to the bottom of the pile. This Storch will eventually fly once I`ve completed it and I`m hoping that there will be only minimal initial commissioning issues. That remains to be proven. In the meantime, we spec`d the motor, speed controller, voltage regulator and propeller size and type.The delivery will no doubt be with me tomorrow.
I`m tired and I`ve been inhaling too many super-glue fumes! Many 03.00am finishes here in the hanger recently have left me a little jaded. Time for bed.The second wing build can wait until tomorrow.
The second wing was built today. The wing ribs are selected and numbered and fitted in a sequential order, dry fitted to the balsa wood upper spar, then a massive 12mm carbon fibre tube is worked through the ribs to the appropriate position. At that point super-glue is trickled into the joints which sets within seconds. After that leading and trailing edge components, then servo trays and the carbon fibre wing mounts are fitted. Again more super-glue holds the whole lot together. The result is a somewhat heavy but hugely robust structure that borders on overkill. Given that ali wing lift struts are later to be added between the fuselage and wings, my reaction is that a far bit of weight could have been saved. As floppy as the tail structure was weak, these wings are hugely over-designed. The motor and other parts arrived as predicted. Trial fitted to the motor box, it is the largest power unit possible fitted in a very small space. The doubled up Lipo pack fits behind the motor bulkhead within an adjustable length motor box. Again, space is very tight for cables. I hope the electronic speed controller will strap under the motor box with the UBEC (voltage controller and power feed for the receiver) being installed within the fuselage. One thing is certain. The propeller and motor cowl will have to be removed to access the power cables when it comes to Lipo recharging. The large battery pack though should enable three or four six minute flights to be carried out without a recharge being needed. My initial take on weight and balance, ie centre of gravity position is that this model will require some lead ballast to be added to the nose of the model.
Here we see the power control system for the motor. The black unit to the left is the speed controller. The three cables connect to the motor. Cables comming out of the right hand side of the controller link to the Lipo battery pack. The long cable with the circular ferrite anti-interference block runs to No 3 channel on the radio receiver for throttle control. The small UBEC at the bottom of the picture is a voltage controller for the receiver and control servo motors. This unit keeps the radio receiver alive even if available motor power has been consumed. Even with motive power consumed, flight control although in an enforced downwards direction, can still be retained.
That`s it for tonight. Try the Bovril tip. You know it makes sense!
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