Bruce Collinson

Gary, Meant to ask; are you proceeding with the standard alloy wing tube? The reason I ask is that as well as the muddle re the c of g, I picked up from an American forum that the tube is prone to bending in enthusiastic flight. I spent too long trying to source a carbon replacement but apart from a Chinese source (call me old fashioned, but ...) I couldn’t find an exact fit and ended up with a loose fit inside the alloy tube. Then, I couldn’t get a consensus from my elders and betters as to whether the carbon needed to be packed out and if so, with what. I’d be interested to hear your opinion on that. My amateur structural engineering instinct was that as soon as the alloy deflected by say 2 or 3 mm, the carbon tube would accept the bending load and the alloy would recover. BTC

Gary, looks excellent. You’re giving me ideas and inspiration. Forecast seems to be improving for the weekend so fingers crossed and do please report back. Are you flying it like this without any blanking inside the cowl to channel air over the head, per Brian Winch? I had assumed it would be needed with a large cowl opening ahead but very little exhaust cross section. BTC

Bought a Kuza clear fuel tank at Weston, made in China of course; says it’s petrol suitable but has unrecognised blue tubing, alloy screw in Cap with O ring. I wonder whether anybody has experience of these and in particular whether they are indeed petrol proof? Classic England performance, almost snatching ignominy from the jaws of victory. I do wonder though whether the Video Refs are natives ...... BTC

Agree with John on both counts; seems unlikely that the maker would include struts unnecessarily. Tailwheel may look slightly ungainly but it ought to steer and absorb bumps. Both items fitted to my Mentor, tailwheel a replacement for a slightly lightweight original and what was needed in practice were two stiffer springs. Sea fishing quick links are a good way of attaching these and indeed closed loop cables, if you want to be able to adjust them without kinks appearing. A swivel further assists and this plane is big enough for them. The Mentor wasn't supplied with struts but dark web chatter from US (dark chatter, not the dark web ... as far as I'm aware ...) referred to lost tails and writeoffs so I fitted them. OK, hardly the aerobatic aspirations of a Yak but a big 20cc petrol powered plane. Don't use a butane soldering iron for film without a heatguard; mine spills heat out of the side and can cause collateral scorching. Shame as it's adjustable. excellent posts GM, you're cantering ahead and I remain glued to your solutions. Got tank at Weston, may have time to try a fit tonight, BTC

rSomeone tell me how to incorporate photos into this thread. Gary, this is very helpful. I too struggle with the rear tank former and will fit a larger tank hopefully to the front former but then stuffed with foam rubber. My throttle servo is just behind the firewall with a short thick Bowden cable and the ignition module is on the in side of the firewall, both on the premise that tail end weight to achieve c of g will be exponentially lighter overall. It means I have several cables to route around the tank but I supposed they will be simpler and cleaner than routing a throttle linkage. Please keep the photos coming. BTC

There are currently I think 4 Herons flying at our club, all on Spektrum txs; two have Lemon telemetric rxs with vario and a third is about to have (mine) when I've mended the Wot 4 tail, plumbed theYak, maidened a little Sukhoi, got an ASP to idle and transition, solved Middle Eastern peace and fused the atom. They seem to work very well, as generally do Lemon rxs. The ones being fitted here have volts and temp built in. Beware import duty. Hope this helps. BTC

Thanks Gary. This is consistent with what we (my former tutor) and I concluded. How far off flight is yours? I’m about to start tank measuring ....

Gary, Thanks. There's a strong implication that Seagull's recommended c of g is at best ambiguous and at worst erroneous; caveat volucres! Never even considered binning their tank, that may well be the solution, dispense with the awkward former/elastic band and wedge from the back. Ta. Thanks for the wrap lead too. BTC

Gary, I'm building one of these for a DLE 20. It's fairly well on, stalled by flying weather and the tank. Whilst I remember, I've fished with Dyneema/Spiderbraid/gelspun etc and they share characteristics; hard to cut, hard to knot and will cut your digits clean off before they break. Allegedly. Try a simple overhand knot in the free end, it will stop knots slipping. Reference angling knots online for anything fancy. Dot of cyano? I have a spool of kevlar flytying thread, similar but much finer, great for wrapping onto c/f tube before screwing clevises etc. to prevent splitting. I may well use Graupner 4mm alloy horns for the tail struts as I have some left over from a Maxford Mentor and they're neater and lighter. Anyway, the tank; the least impressive bit of the whole plane so far; what are you doing to secure it, bearing in mind it's awkwardly accessible and rather hard mounted? Have you decided on the C of G, upon which there is much online speculation and a large degree of uncertainty? I suspect yours will maiden first and I will be keen to hear how you get on. BTW where does the 3mm wrap come from? Not seen it but it looks sensible. BTC

I think I have one (FP ... 25 yr old cooking 2 stroke?) but it goes with a now-redundant engine. No use seperately. Would you bid for both? Bruce Collinson, Leeds.

i "invested" in a 4Max quad charger last year and it's brilliant. Any battery type, discharge/cycle etc, 4 x 100W and runs on mains or a 12v leisure battery. Comes with oodles of cables and connectors and merely needed a 3 m mains cable as the supplied one was a bit short for comfort. £140-odd and doesn't owe me a penny. At the field I generally fly twice then start recharging. NB it will charge down to a 1S LiPo which a smaller (I wrote "budget", which it wasn't really) charger I bought won't do. (ignition for petrol plane). Was it John Ruskin who articulated the principle that buying "budget" ended up costing more anyway, when the first widget breaks/fails/underperforms and you end up buying the better widget anyway? If it was, he should have kept his mind on it ...... BTC

Thanks whoever above pointed out it was "your item for sale" in pidgin English with no reference to the specifics of the item (an OS 55AX) and hinting at a bank draft. I took it to be slightly odd but it's clearly a scam. I asked whether my correspondent used Paypal and it has, as they used to sing at Elland Road, all gone quiet over there. I suspect many/all of the items for sale have had similar attempts; moderators, worth putting out an APB? Agree with Bob about photos and will happily send if anyone doesn't know what a 2-tank OS 55AX in a box looks like. BTC

Neil, Wish I'd seen your build blog sooner as I maidened my ARTF Acrowot last Saturday. It has the same setup as George recommended except it uses 5A 4S LiPos (same as my Wot 4) and an ESC at 60A. George has specced and supplied three power trains for me in the last year and I rate him. Yours ought to be quicker on 5S; mine was very cool all 3 flights, cooler than the Wot 4. Unfortunately the battery hatch came off and the replacement has been heavily modified to prevent repetition. One of my clubmates finished one recently and left the cowl cutout slightly narrow so it overlaps the front edge of the hatch and I wished I'd seen it sooner. Not sure how much similarity there is between kit and ARTF hatches etc but hope this helps; mine's tail heavy (I dislike plastic clevises) and the cart bolts look weedy, too small to risk nylon and the blind nuts are hidden behind a bulkhead. I'll look out for updates. BTC

Isn't this the answer to my earlier question? A ready made switching device with, apparently, enough capacity; bit of vaseline on the conductors, lots of epoxy on the back; may well get a couple for my son to hand-deliver from LA as the pound seems a little less weak against the dollar.

Several issues arise (again). I know a bit about tinted and polarised lenses as I have fished for 55+ years and fishermen make aeromodellers look like amateurs in the tackle-tarting business. I've been through most of them, starting with Polaroid, via Costas, Oakley, Smiths etc including some pretty expensive stuff. Pre-recession I fished in the Bahamas for bonefish three times. They are notoriously difficult to see so we all took every pair of glasses we had and we struggled like mad. All the guides were wearing Smiths; we emptied the lodge shop and the second year we had a couple of pairs each. Subsequently a pal fished on a different island where everyone swore by Maui Jims, which we'd tried and swore at. Lesson 1; light is very funny. Bear in mind that a sight fisherman needs one thing only and that's glare control, although colour filters can help. Different water = different light. I stick to the Smiths as the best all-round FOR FISHING. I wouldn't risk them for flying. It's hard enough when I know which is up and down. Most of the middle market, I believe all the Ray Bans, Oakleys, Costas etc all come out of the same Italian factory. Many will be identical lenses but with different names. Lesson 2; try them first. Last week in bright clear sunshine, the light was "funny" and it was to do with contrast rather than brightness per se. To my eyes, the amber/yellow/contrast/night vision shade improves contrast best though I know some clay shooters favour orange. Lesson 3; refer to 2 above. Finally, and I didn't start this; common denominators of aeromodellers 2018; early cataracts, optical glasses (hence my preference for overglasses; see previous thread; can still read the screen) and some form of skin issues, solar dermatoses, BCCs or worse SCCs, Efudix, vitiligo etc. In my case, fair haired blond with blue eyes, days spent on top of the old Winter Shed at Headingley with no hat, etc; now means F 50 and wide brim Tilley and that's on dull days. The quack asserts that a tan is skin reacting to an excess of ultra-violent light. Yours in gloom, BTC

Geoff, Really grateful. I'll try to get out more, hopefully this Sat but am minded to fit a plug to the Acro Wot which awaits my pleasure as soon as I turn sixty....something .... tomorrow morning and which is specced for electrickery courtesy of 4 Max ESC, motor and prop and the LiPos from my Wot 5 (4S 5A, biggest that will fit without major modification). A very "sweet" setup in the Wot 5, hoping for similar in the Acro Wot. BTC

Now I remember why I didn't pursue physics at A level. To try to summarise; there's no mechanical switch; safety plugs are the way forward; too long battery leads, say 8"+, = unwelcome inductance; battery leads should be close together; safety plugs between ESC and motor are marginally useful; er, that's all folks. BUT I've seen various plug types. I try to stick to Deans simply for consistency although I recall seeing an ... XC 90? with spark suppressor; any clear superiority here for the safety plug? How important is it to keep battery wires similar to each other in length if interrupting one to fit a safety plug? Plug on the + or the - cable? Finally an observation after two years in my third modelling career. Electric accidents are usually due to unrestrained models. Nobody dreams of starting any sort of i/c plane without a proper restraint. Some modellers arm electrics without restraint.

As a relative newcomer/returnee (2 years) I remain nonplussed by the lack of a simple switch which will handle these currents. You'd have thought by now that the simple demand/supply equation would have prevailed. My Wot 4 has an ESC with a switch, I recall it's a Jeti, which doesn't alter the fact that the battery is still connected to the motor but does reduce the propensity for accidents involving inadvertent stick movements. What sort of parameters apply in terms of cable length difference if interrupting the live feed from to ESC?

Dave, I can't match most of the foregoing on technical depth of knowledge but I'm flying an ARTF Wot 4 into which I can just smuggle a 5000 mah 4S LiPo and with the fairly standard Ripmax motor (Rimfire 40?) it balances fine with no ballast, climbs out of sight, flies 8 or 9 mins to about 40% battery and flies slowly enough to land without constantly breaking the u/c bolts. It's known as a Watt 5. I do recall having ordered a high-ish capacity esc which has an arming switch, could be a Jeti, and my helpful electrically-astute club mates made me limit the throttle setting to prevent auto-immolation If of interest, I'll check its components when I return from foreign parts and give you a list and probably I ought to weigh it too. To be honest it flies so well I'm not too bothered what the labels say.

Rick, here we are. My correspondent Jeremy Harmer confirms that The Optical Shop, Sizers Court, Yeadon, LS19 7DP does indeed retail them, for £12 a pair, but buy two and get the second at half price. Hope this helps. BTC

Rick, am checking source for Remaldi NightSight OverGlasses, handled by Opticaid UK Ltd in Yeadon, Leeds and will revert to you. As they say, watch this space. I have no polarisation issues although they are polarised; I wonder if it varies between manufacturers of Tx screens; mine's a Spektrum Dx9 Black Ops. Cheap as chips but absolutely good enough.

For what it's worth, several of my clubmates use amber contrast polarised overglasses which one of us sources at £10 and I wear these over my non-Reactolite (fell out with those, too many scars on forehead) prescription varifocals and I get on well with them. They definitely improve contrast in that awkward light and don't mess up the Tx screen at all. I had a pleasant surprise when clayshooting last week, never been able to shotgun in prescriptions nor pick an orange clay against grass and the Joe 90s (as they're affectionately known) improved both aspects significantly. If interested, I'll ask Jeremy Harmer for the name and source. Might discover he pays £5 ....

Spooky, this is a topic which has been nattering me. I'm a returnee and morphed straight into what nearly all my clubmates use even though 25 yrs ago I used Futaba. Since starting again a year ago, my new gear went back and came back with a replacement r/x; my tutor's gear went back following a horrific near flyaway and crash when buddied, and came back with a replacement "module" and a third clubmate's is awaiting return. Three out of 30-odd in the last 4 months. Maybe coincidence; turnaround levels have been ok although I waited three weeks for my replacement r/x; one benefit has been the assiduousness of failsafing and rangechecking. I do wonder whether the odd novice arrival is misattributed to pilot error. If I won the lottery (unlikely as I've never bought a ticket) or started again I'd be tempted by top-end German gear. The willingness of one maker to replace and repair out-of-warranty gear f.o.c. is great, but maybe there's an ulterior motive?

Iqon, I'm building one of these. Can I ask a few questions? What engine? Any nose weight needed? Did you brace the tail; if so, how? Mine is at the stage of rear servos and closed loops fitted but not connected as I don't want the tail glued in till the engine (a borrowed Zenoah 25cc) is fixed and plumbed. I will brace the tail and am wrestling with carbon tube as it will only be needed on the upper surface and previous experience with wire was unsatisfactory. Fixings with enough tensile strength are a bit awkward though. Has your u/c been up to it; any other tips/mods whilst mine is still in bits?

I have just had my first proper crash since returning to the hobby after a very long hiatus. My Wot 4 foam, latest version, 3 weeks old, shed its wing at the bottom of an adequate loop. Wing ok, fun in 3 bits BUT on close examination, the experienced crew at my club discovered that the dowels at the front of the wing could scarcely have been engaged in their holes, apparently due to a manufacturing fault. As this is a contractual issue with the retailer I will be taking it up but I wondered, firstly has anyone out there had a similar problem, and secondly if you've bout one recently, check the seating before flying.