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Just a reminder guys, don't forget, next week is diarrhoea awareness week. Runs until Friday.

When I built my Hawker Sea Hawk with both its inlet and exhaust bifurcated I really struggled to make the ducts effective within the limited space available made worse by the fact its 'portly' fuselage forced the inlet and exhaust openings to be rather far apart. The Sea Hawk has a triangular wing root inlet. This has to change smoothly and aerodynamically to the circular EDF inlet. In addition it has to translate sideways to the fuselage centreline. Finally the left and and right hand ducts have to merge. Lofting allows Free Cad to mathematically generate a complex profile transitioning from one shape to another. Could this be a relatively easy way to create a very complex shape that could then be 3d printed? The first attempt going from a triangle via an intermediate circle to a bigger one with a sideways offset. By positioning the shapes diametrically opposite lofting forms a symmetrical "Y". Although the inlets and outlet are positioned correctly it would not be that aerodynamically efficient. By adding an additional intermediate profile and adjusting both their shape and position as well as quite a bit of trial and error. Now the side ways transition is gradually applied and terminated to minimise the airflow rate of direction change. By its nature lofting generates a hollow file which is ideal for single wall "vase" printing. Printed in LW-PLA but at 50% scale just to see how it came out. It weighs 2.3g. Even at the required 55 mm diameter it would still only weigh 10g. The much less efficient shape PLA printed inlet duct actually used in my Sea Hawk weighed 25g. Lofting can produce a really complex yet easily adjusted shapes. Fine for something like a duct but not so obvious an application for a 'structural' component.

There are 5 built-up formers in the rear fuselage. My preferred method of making formers which are basically rectangular is make them inside a pair of framing set-squares, rather than over a plan where it’s hard to keep to drawn lines. Once the parts are cut out the first corner can be pulled into one set-square, then the other side can be aligned accurately using the other set-square. It does mean transferring measurements but as the squares have inches on one side and millimetres on the other it’s a quick job to measure and cut any cross pieces to end up with a former with parallel sides. Trial fit of the formers

As everybody has stated the coloured backgrounds to text are awful! I wish the Editor would choose more one off articles rather than columnists. Too many articles from too few people eventually bore readers. When David Boddington was editor of RM, then RCME, AMI,MF, RCSQ etc he seemed to get articles from aeromodellers that were not regular writers but people who had something special to say. This made the magazine really interesting and never boring.

I don't understand this comment Chris. Why keep upping rates until you run out of travel? I only use high rates for spinning. You can fly most aerobatic manoeuvres a model is capable of with quite low rates and just move the sticks to their limits. A beginner using high rates can get into trouble with pilot induced oscillations that usually don't have a good end. Am I missing something?

In the meantimetime on to prepare the horns for the working surfaces. The bottom of the horns needed to be scored for the glue. Also some of the film needed to be cut away such that the horn base will stick to the wing rather than the film. All basic stuff. The slots in the wing are sufficiently well cut such that the horns slot in without and remedial work. The ailerons and elevators are essentially the same fitting. The rudder horns are for a pull/pull system (rear push rod setup also catered for) and are all in one. All these these fittings are going to be glues with gorilla glue. Now where have I put that pot ...........? 🙄

I once flew my Panic all afternoon about 10 flights, used 3/4 gallon of fuel running on a 500mAh NiCad and still plenty of battery left using all Futaba 148 servos.

Tiny, you are on an expensive hiding to nothing here. You are on a common exit route from the hobby. Your second plane after the glider should be a little more difficult to fly, and because in your inexperience GOING to break it, and normally fairly quickly, because most learners get a flush of confidence for the second model, should be cheap and easy to replace. Sorry re straight talk, but I have seen this failure route before, walk before you run mate.

I just learned today that if you have a breakdown in an electric car you can still use the AA! However if it's a small electric car you have to use the AAA.

Any decent standard servo will do. We used to use Futaba 128's in the Panic back in the 80's without any concerns and as far as I'm aware the laws of aerodynamics & forces have not changed. From a magazine of that era: The inflation adjusted price today is £40.

I have used a layer of one or more short pieces of heat shrink tubing to increase the diameter of a prop shaft to suit a hole in a prop. Shrink it in place with a heat gun until the prop is a snug fit.

No-one has paid road tax since before WW2.

As a self confessed petrol and diesel lover, I think this latest joke from the government is extremely funny. "As of 2025 electric car owners will have to pay road tax" 🤣🤣🤣 The phrase "I told you so" springs to mind. Irrespective of who is running the country.

Yes John, fittings seem to be of reasonable quality. As to the hinges most of the accessories provided are Kuza make although I am not convinced the hinges are. When i visit the workshop in the next couple of days I will check and post here to answer your question. Leave it with me.

I think Kevin would be highly delighted to receive articles from modellers. In fact, I think he mentions it regularly in the magazine. I don't think DB had it easy getting them ! New years resolution for all the forumites. Send something in to Kevin for publication. Doesn't matter what, A letter, photo, show experience, plan and article, anything. Just DO IT. If you will, I will. Promise.

Only electric APC props have adaptors!

Nice to see another Whirlwind, this video from a club not too far away from me at Aix en Provence,,,

Ordure, ordure!

There's a website giving more details online, don't forget to log out.

Only just seen this. Thanks very much Peter and Graham for the offer, that's very kind, but it'll give the wife something to buy me for Christmas so don't worry. Just ordering the kit from Sarik now. Will keep you posted on progress. Yours is looking good EarlyBird.

What you guys have bought will be fine Keith!

Top up the central heating tank Frank!

I think I will go for a Riot then Batteries I have 2s 1500 x4 3s 2200 x2

Wing build continues with marking and cutting the holes for the mylar hinges both in the wing and aileron. Mylar hinges are 12.5mm width by 30mm long has been found to work. Note these will also be pinned into place later as described previously. Wingtips have been put against the end of the wings and marked so that these can be sanded to shape. Leading edges have been attached to both wings and initial razor planing and sanding to meet bottom and top wing surfaces undertaken prior to completing the final shape. Spruce strips have been added and glued in place so as to attach the servos into the wing.

We even flew them with piped 60s . My son had a Panic with a piped Rossi 60 rear exhaust fitted to his Panic Incredible performance and never had any problems with control with Futaba 3001 servos fitted . 3001 were standard 148 internals but had a ball race on the output arm that reduced play and slop. Plus they were not power hungry like the modern do called "Digital servos" . The digital types are fine and probably needed on the big 3D 50cc plus models but then you have the carrying capacity for a big batteries to power them. You don't have that luxury on a standard Panic . For best fun per £ use the KISS principle , Standard good quality servos are more than adequate.

As per Graham Bowers post 👍 .It's perfectly normal for ABC type engines to be tight at TDC, something would be wrong if it wasn't. Run it in in short bursts tuning it to run at high revs but but just slightly rich, not max revs but near to max .Run for a couple of minutes to allow it to get up to max temp then stop it and allow it to cool down fully . Repeat process a few times but don't run it at low revs yet or you risk damaging the con rod or crank . After a few cycles of running and cooling tune for slow running as well then put in airframe and fly it. Use a good quality synthetic based fuel. Once the tightness over tdc eases its run in . Even when run in you should still feel a slight tightness at tdc. Unlike older generation engines the modern engine of this construction doesn't take very long to run in .

The firewall air outlets have now been cut, this is what the engine is going to have to live with. Progress and setbacks. Having produced 4 decent curved longerons, looking at photos I discovered that each fuselage side where the doors are, is flat. The fuselage sides aren’t single curve around the cockpit area, but two curves with a straight section in between. The laminated longerons were not going to change their shape easily so nothing for it than to redo them. So much for trusting drawings. The Mark 2 jig was made and hopefully an improvement incorporated at the same time, it now supports the wood from both sides. In retrospect, making a jig which is itself a clamp is much better than just clamping to a single side…and no more difficult, you just use, instead of throwing away, the other half. the picture below shows the two crutches produced (one above the other) and holding their shape, with nothing but a few mini clamps to keep them in position while the cross members are glued in. With the fuselage sides being curved, the wing seat which would be 3/8” would also need to curve. Balsa that thickness is not going to curve easily so laminating came to mind again, so I made a jig – you’ve guessed it – to the old shape of the side. Functional jig, just the wrong shape. The hatched area shows what the wind seat looks like in plan form. ...and what it looks like when out of the jig With the revised shape of the sides, I now have a wing seat which is the wrong shape. Actually all is not lost as the front part of the seat didn’t change, the straight section starts from about 40% back from the leading edge, therefore I can use the good bit and make a straight section, which can be cut directly from 3/8” sheet. A bit of good news, the wing and tailplane ribs which have been designed on my (don’t laugh) old Compufoil program and LMA member, Bob Maltby cut them for me. He’s made a really good job of them, crisp cutting with minimal burning and a prompt service as well. he had returned the ribs within a few days of getting the dxf file.

See the manufacturer's instructions "Engine construction" box on page 1 that makes a statement about the tightness at tdc. The running in procedure is on the second page. Must admit, I usually do the first 4 or 5 runs on the test bench, however stick exactly to the recommended throttle and needle positions. The old softly-softly running in procedures of ferrous pistons and cylinders are to be forgotten as it's important to get heat in to these to expand the cylinder liner. https://www.os-engines.co.jp/english/line_up/engine/air/aircraft/manual/15_25la_eg.pdf

Looks tidy to me Paul!

Nothing better than a clean workshop for painting.🤩

My understanding of the plan arrangement is that the metal plate has a tang that the wing slides under (with the fuselage inverted!), the wing is kept square in planform by the tapers on the ends of the crosspiece and the leading edge cut out, the tang is hidden by the fibreglass cowl. I would want to let in some spruce or ply though where the tang contacts the wing for longevity. I've seen a version of this with the plate the same but the tang engages in a slot in ply midway between the upper and lower aerofoil surfaces.

This summer I managed to build a tail gear mount. And after tidying up the workshop I started with servo and receiver installation.

In summer 2021 I took the Whirlwind to a Warbird meeting, together with my Arado 96 of same 1/6 scale.

Whilst not perfect scale I think these zorst stacks look quite good (not of my making, apart from the paint!)