Nick Cripps

I had a great day's flying today at Kitridding Farm with the Windermere Model Waterplane Flyers. It was rather chilly but mostly clear and sunny with only a light breeze. Fellow club member Mark and I have a few matching models and have great fun flying them together. Top to bottom are the HK Skipper, FMS Kingfisher, Eflite Turbo Timber and the HK Tundra. The latter has been fitted with LEDs strips for night-flying and looked great in the dusk.. up to the point when a tree jumped out on a low pass 😪

That's incorrect, the AR620 is not an AS3X or SAFE receiver and does not have stabilisation.

That looks neat. Fairing on the outside?

Welcome to the forum Graham. The Bigfoot is a fine little model that works well as a trainer and is capable of basic aerobatics with increased control surface movements. They are a popular model in my local club. I can only echo the previous recommendations to search out and join a local model club.

Assuming your leading edge sheeting is interrupted by the engine nacelles, can you not substitute 3/32 for the inner section?

That's a good point, kc. Whenever I saw David at Billing, or Old Warden, Ken Swailes was always present. Ken built many of Boddo's models and was a big part of his life. After Ken sadly passed away, Boddo was never quite the same and seemed somehow lost without him.

On one occasion at Billing Lake near Northampton many years ago, I was flying my favourite waterplane of the time, an ARC Cessna Cardinal. The ARC range are sadly discontinued now but in many ways they were perfect for waterplane flying as they were moulded from plastic (ABS, I think). All the models in the range (Ready, Beaver, Jupiter, etc) shared the same float set but with different fittings for mounting and have been quite popular over the years. They were slightly heavier than the equivalent built-up models but that was not really a problem; well, most of the time. Boddo wandered over to look at the Cessna and told me that he had recently been flying one for a magazine review. He further went on to ask me if I had tried spinning and, as I hadn't, he suggested I try it as it was "interesting". So on the next flight, I took the model up a couple of hundred feet, throttled back and started feeding in up elevator. As the model slowed I pushed both sticks across and the model dropped into a perfectly-developed spin. After a few turns, and with the lake fast approaching, I let go of the sticks, expecting the Cessna to recover just like all my other models would do. I was surprised to see it carry on spinning, so I quickly put in opposite rudder and aileron, at which point it rapidly flicked into a spin in the other direction. I was by then in full panic mode and desperately banging the sticks into the corners in a vain attempt to recover but, to no avail, as the Cessna hit the water with a splash. Boddo, standing behind me, guffawed with laughter and said "I told you it was interesting, didn't I?"

True, but they are both older designs which were heavily influenced by the free-flight models of the time. Maybe it was a bit of a sweeping statement but you'll rarely see a lifting tailplane on a modern RC design, unless they are trying to replicate that style of model. Sorry for the distraction, Steve, back to the Mighty Barnstormer.

That's how I see it too, Steve. Odd that it has a lifting section tailplane, they are normally only seen on free-flight models. I guess Boddo's intention was that it would be flown that way, with just the occasional intervention by the pilot. Make sure you check the controls before flying, unlike Boddo...

Another vote for Eze Tissue from me. I've just covered a Tomboy in tissue over doculam and really struggled to find a tissue with decent wet strength until I tried EZE Tissue. Only downside is that you have to use a water-based dope as proper cellulose can wash out the colouring dyes.

Same huge tailplane on the Sea Stormer, bigger than the wingspan of some of my models!

Looks good, Nigel, I'm interested to see how your twin fin & rudder arrangement works. I've been pondering a similar twin engine twin fin design for a while but always get hung up with how to actuate the rudders.

This is my starting equipment, carried in the flight box about 100 yards from car park to pits. The box also contains a some tools and a few spares such as glowplugs, wing bolts, etc. Standard 12V starter with 4000mAh 3s battery - good for all my glow engines up to and including a Laser FT-200. I've bolted a thin ply plate on the flat section of the starter end caps to carry the lipo, which is held in place with a strip of velcro underneath and a strap around. I generally start 2-strokes by hand using a chicken finger and just use the 12V starter for 4-strokes (and reluctant 2-strokes). I use a simple fuel pump which is fitted with a 2-way switch and powered by an old RC car 2s lipo. Backup is a hand-operated pump. Glow is provided by a common & garden glowstick containing a sub C-sized Nimh cell. This cell is usually charged before every flying session but the lipos on the pump and starter seem to last ages and are only charged a couple of times a year.

Hey Ron, look what Elmo has been up to while you've been preoccupied with videos: Elmo responds to outpouring of angst on social media

I've still got my slide rule from my schooldays and a circular one that my father used to use at work. I took my O and A levels around the time of the crossover from slide rules to calculators so I became adept at using both. My elder brother was 4 years ahead of me and didn't benefit. One really useful skill that the old methods taught was learning how to estimate the order of magnitude of the expected answer (you had to as there is no decimal point on a slide rule). I found it very frustrating at work in the later stages of my career in engineering, as the newer graduates often just believed the answer that the computer gave them, even when it was obvious there was an error of several decimal places!

Thanks, Stu. Have you still got yours?

Just what the thread is for! All stories and photos welcome here.

That's great, JD, just the sort of story I hoped to bring out with this thread.

Prompted by a comment on another thread, and also the BIMBO articles in RCM&E recently, I thought it would be a good idea to start a thread dedicated to one of the most popular designers of recent times, David Boddington. DB, or Boddo as he was often known, was a prolific designer of models and also some full-size replicas used in various TV and film works, and also a former editor of RCM&E (as well as a few other publications). Having a common interest in waterplanes, I met Boddo a few times over the years at various events such as the British Waterplane Association meetings at Billing and Nottingham, and also on the odd occasion would bump into him at other venues such as Old Warden. I didn't get to know him particularly well but I always found him great company and, as many will attest, he always had an amusing story to tell, whatever the occasion. After he sadly passed away in 2010, I thought I should build one of his designs as my own personal tribute to the great man. There were many models to choose from but, for me, there was only one choice, the Sea Stormer. The Sea Stormer is based on one of his many Barnstormer designs but modified to low-wing configuration and styled like a Schneider Trophy racer such as those designed by R J Mitchell for Supermarine. Sea Stormer was published in the July 1996 edition of Aviation Modeller International, with the prototype built by one of Boddo's fellow club members, Andy Ward. Spanning 69", the Sea Stormer shares its wing with the Barnstormer 72 but with a modified tip shape. The structure is typical Boddo: partially-sheeted with cap strips to the rear of the spar and barn door ailerons to the wing, a traditionally-built fuselage, sheeted at the front, open structure aft of the wing, with the whole airframe covered in Solartex and, of course powered by a Laser 90 four-stroke. The prototype was test flown by Tony Chaplin (former BWA Chairman) at Billing Lake near Northampton and proved a great success. Two larger versions were also built and flown with Laser v-twins, one by Boddo himself, the other by Neil Tidey, who still occasionally flies his version at Billing. My own build was one of those marathon projects - you know, the sort that progresses in fits and starts as bursts of enthusiasm appear - which took place over about ten years and included a house move. The wing was built first and progressed quite quickly (for me), thanks partly to making use of a precut set of ribs from DB Sport and Scale saving the tedium of cutting them all out of balsa myself. The tail surfaces were next, all built up from strip balsa with sheet elevators and rudder. Finally the fuselage then the whole lot, like the prototype, was covered in blue and silver Solartex, apart from the rudder which was covered in glasscloth. The floats were hot-wire cut from EP foam, covered in poplar veneer and then glassclothed using epoxy resin. The engine cowl was moulded in glassfibre over a blue foam former and nicely encloses an OS 90 Surpass. The model was finally finished in September last year, but sadly just too late to fly at the final BWA meeting at Nottingham, so is likely to get its maiden flight at Billing Lake when the new season starts in April. So that's my Boddo story. The model has been a long time coming but I'm sure it will be worth it when Sea Stormer finally takes to the lake (and the skies hopefully) in just a few months. If you have a similar memory, or wish to show us your Boddo model, please share it in this thread.

The best shape to resist torsion has a circular cross-section. Think of things whose sole purpose is to transmit a twisting force (torsion) such as a car propshaft, it is circular in cross-section. To keep the weight manageable, the shaft is actually a tube whose thin skins are sufficiently strong to transmit the load. The D-section on our models formed by the curved sheeting from the leading edge to the spar (top and bottom) combine with the shear webs on the spar to create an approximation to a thin-walled tube and hence can resist the twisting in the wing due to control and aerodynamic forces. The purpose of spars is to resist the bending load in the wing, created by the weight of the model and any additional g-loads in loops etc. The spar contributes very little to torsional strength which you can easily demonstrate to yourself by taking a metal ruler and seeing how easy it is to twist along its length. If you then put the ruler on its edge and try to bend it, you will see how well it resists bending, just like a spar. The optimum structure for a spar is to have 2 flanges separated by a shear web (think I-beams). The further apart the flanges are, the more bending load they can resist (up to a point when the shear web fails due to buckling) so having a flange close to the upper and lower surfaces of the wing section is ideal. Even better, the shear web between the flanges (holding them together) also forms part of the D-box mentioned above and contributes to the torsional resistance of the wing - bonus! The wooden structures we use in model aircraft have been optimised in both the model and full-size aircraft world for decades and, where properly designed, provide the necessary strength with the minimum weight. People like Ivan Pettigrew clearly understand the principles involved and have created some impressive models.

There's your answer, Steve, and much more eloquently than I would have said it.

Steve, you'll find that many of DB's designs followed the same style of construction. I recently completed a DB Sea Stormer (see below), which is basically a low wing version of the 72" Barnstormer modified to look like a Schneider Trophy aircraft of the early 30's, and I would imagine the Mighty Barnstormer is very similar in terms of its major construction points. Ask away if you have any questions. It is also interesting to note that the rear fuselage construction of the DB Auster is very similar, as shown by Danny Fenton's build log a couple of years ago, and I would expect other parts of the model to be similarly-designed.

Double negative?

My building order is usually tail surfaces first (to ease myself back into building) followed by the wing and then the fuselage. I love building wings but hate fuselages so they always get left 'til last!

Post your picture up on this thread https://www.rcgroups.com/forums/showthread.php?3732835-Spektrum-NX-Transmitters explaining your problem and ask for guidance. I suspect this has been asked about before but actually finding the relevant information in the 800+ pages is quite a challenge. Andy Kunz frequents this thread and actively encourages questions here rather than direct contact with him by PM as it then allows the knowledge to be shared with the community. You might also find what you need here https://www.rcgroups.com/forums/showthread.php?3848191-Spektrum-NX-Transmitter-Info-and-Tips but if not, there is lots of useful information here to help you get the best out of your NX8.