Piers Bowlan

I bought this motor, Turnigy 3548/6, to go in Peter Miller's Dragon Dancer 2 design, the free plan in DEC 2012 RCM&E. I was planning to power it with a 4S/4000mAh LiPo for the electric conversion. I am using a Turnigy Plush 60A ESC, which has a switch mode BEC. If you are planning to use a 3S LiPo I would be tempted to use a Higher KV motor (1000kv?), although I am no expert. Perhaps someone more knowledgeable could make a suggestion. If this model was built 20 years back are you planning to use the original standard sized servos? I just thought if you fitted some modern powerful micro servos you might save quite a lot of weight.

No, don't be silly, a Hawker Sea Fury is next! Nice wide track landing gear. 120 FS (or petrol 2 stroke) up front. Great!

My KK Hurricane control line model came fitted with this engine, turning a three bladed plastic prop. The little spring starter worked well and saves cut fingers. The engine was screwed to the black plastic tank which in turn was retained by being wedged between the two fuz halfs. The dummy Merlin engine exhausts were part of the tank moulding and protruded through the fuz sides and so locked it all in place. I used to run it on Nitrex 15 too.

I would like to scale it down for a single Wren 44 but to what scale? What would be the desired span and the estimated weight of the scaled down model? It would make it easier to transport too! Edited By Piers Bowlan on 05/06/2013 16:29:56

For an unswept flying wing (planks)15-20% MAC is a good starting point for the C of G. At 15% MAC you will need a lot more reflex but 'how much' is down to trial and error. The C of G calculator posted by Engine Doctor works well for swept/tapered wings.   As an aside, I have scratch built a few flying wings over the years and I have found that broader control surfaces with smaller deflections tend to work better than narrow strip elevons. Just my 2p worth!   What are you building by the way? Edited By Piers Bowlan on 01/06/2013 07:46:57

Not if you want the wingtip to stay on.

EPO has a 'greasy' surface that does not adhere too well to epoxy which is why Multiplex recommend their Zacky (thick CA) on all of their models. An epoxy/foam joint may look strong but may fail after a firm 'arrival'. I second what SmarTmartY says. As a technique I have also just held the broken pieces of foam firmly together whilst wicking thin CA glue along the join line. With your third hand (!) spray the area of the join with activator. Voila! You may want to wear disposable plastic gloves as it can be messy! I managed to break off about three inches from the wing tip of my 2.6m HK Fox in my workshop. Doh! I just glued it on again with CA but reinforced the join by cutting six inch slots span-wise across the join. I then cut some thin carbon strips (10cm wide and .5 thick) which I pushed into the slots. Then some more thin CA was wicked along the carbon strips and sprayed with activator. That wing tip is now the strongest part of the model and has survived numerous less-than-perfect landings. Incidently the HK Fox is a great model too, once you sort out a couple of quality issues with it.

Didn't mean to be rude Greg, the 'proper model' comment was supposed to be tongue in cheek .

I don't wish to sound negative Greg (but I will just the same . The model is too small at 38in span and will get smaller very rapidly as it flies away from you so you will become disorientated even quicker than normal! One of the other problems with this model is that it is made from EPS (expanded polystyrene) which is very fragile and will disintegrate as soon as you look at it! Scale models? You can buy loads later when you can fly consistently well. Get something bigger and if it is foam make sure it is either EPO (Expanded Poly Oilfin) which is tougher than EPS or EPP (expanded Poly Propylene) which is indestructible. My recommendation (by PM) was either the Multiplex Easy Glider Pro or their Easystar (both EPO). They are good quality proven models, can be repaired easily and spares are available too. If you are to go it alone give yourself a chance and get a proper model! Edited By Piers Bowlan on 12/05/2013 13:11:40

It is not completely clear. I would say that surely the 'complete set' includes the additional wood pack etc. plus the plan? Best give My Hobby Store a ring to check;- 0844 8488822.

No more pills Greg, get one of these instead Here. Cheap as chips, flys in anything and addictive fun. Whata-you-mean it's not a trainer? Its unbreakable (or nearly). It will get a bit battered but you will end up getting another eventually as you will be hooked. Every one should have a Wildthing for when it is too windy for sensible flying! Enjoy.   Edited By Piers Bowlan on 11/05/2013 07:29:51

Instructor to pupil. 'A little late on the round out Hoskins'

"Pointless poll" That's a bit harsh isn't it? It's good to talk! What might be worth considering is what do you mean by 'crashing' which is a pretty emotive word and one so beloved of the media when referring to full sized aviation accidents and incidents. For me a crash is a 'bin bag job' or at least something which is going to require a major repair. Some might consider a crash to be an 'unintended arrival' due to any number of reasons. For example, caught by a gust of wind just before touchdown resulting in one of the landing gear legs being ripped off. A crash? Perhaps not but an incident yes, and not to mention really annoying . Another example; flying that new manoeuvre you are practising just one mistake too low. You make a recovery but just a millisecond too low/late and end up making an unexpected and rather heavy unplanned landing. Result, a cracked cowl. A crash? Not really, you got away with it that time, the model wasn't wrecked just a minor repair. Pilot error certainly but I think you have to define 'a crash' if you want to use that word in this poll. Or maybe it is just me being pedantic. Edited By Piers Bowlan on 11/05/2013 06:36:28 Edited By Piers Bowlan on 11/05/2013 06:42:39

I am not too sure what this poll is going to achieve as I think people will agree that most crashes are generally caused by pilot error simply because it is such a 'broad church'. Including such things as disorientation, stall-spin, and mid-air collision to name but three. As far as the other categories are concerned what about servo failure? Fairly common I should think (I have had two). Also ESC failure either because it was a low spec. unbranded ESC in an RTF or because the BEC was overloaded by too many servos. In that instance surely that is pilot error again? Crashing due to flying in 'adverse weather conditions' Is that not pilot error too? No one makes you do it, your decision to fly and risk crashing the model.

Like you Wiiispa, I work unsocial hours and most weekends too, so a club did not really suit me either. The model I built thirty years ago was fast, twitchy, unstable and fragile -not what you generally want in a trainer! Added to this I used to fly in some pretty wild conditions in Scotland at the time. Consequently my ratio of rebuilding hours to flying seconds was not very good and it is a wonder I did not give up -except that by then I was hooked. So it can be done but with the benefit of hindsight perhaps not the best way to do it. There are some good hills around Folkstone so get yourself a Wild Thing from Soar Ahead Sailplanes as well as building your balsa model - you will have a blast I promise you! Finally, Sims are great especially when the weather is bad or it is the middle of the night (!) but they are no substitute for the real thing so start building and just get on with it is my 2p worth!

'The Balsa Cabin' Here, do grades and ship to Europe too.

Terry, rather than laminating how about making them up from 3/32 sheet top and bottom, assuming you have some of that. Add a few triangular riblets plus a sheet LE. Will need to reinforce where the hinges are. Probably take no longer than shaping a thick sheet, if you had one that is, and lighter too. Edited By Piers Bowlan on 09/05/2013 09:38:18

'quick squirt of wd40 works well' Actually Linds WD40 will cause some covering films to stretch and go baggy so should be used with care. Always test a scrap piece first. I know the old solarfilm is affected in this way but probably not the solarfilm super shrink polyester. Piers.

Just ordered a Park Scale Mini Drake (micro flying boat) from them - should be fun. A great pity they are ceasing trading, a sign of the times sadly.

Wiiispa, Building a balsa model and flying it is very satisfying but when you complete your new model it will be a test flight. As this will also be your first flight, so haven't learnt to fly yet, the outcome is not likely to be a happy one - the model will probably end up in bits after a few milliseconds (ask me how I know!). Get someone else to check the model out and do the first flight to get it trimmed out and the control throws etc. sorted. You will then have a flyable model. By all means build but chose a design that has lots of wing area, stable and slow flying (Junior/Super Sixty?), It will be forgiving to fly and probably survive the odd tumble. Alternatively get a foam read to fly model like a Multiplex Easystar for example Here or an Easy Glider Pro or Fun Cub perhaps. These models fly well and are easy to repair plus spares are available. They will enable you to get lots of 'stick time' and progress quickly. If you still want to build your Tucano, as mentioned in another thread, do, You will have fun which is what it is all about, even if the flights are likely to be short!

Hi Wiiispa welcome, What aspect of the hobby interests you, Powered models, (Internal combustion or electric powered), Gliders, Helicopters, etc. Also do you fancy building a balsa model or do you prefer an almost ready to fly model that needs only assembly so that you can concentrate on the flying? What have you got so far - or about to get? Piers

Off-setting the engine/motor thrust line by three to five degrees to the right relative to the aircraft centerline will reduce your torque roll to the left after T/O. If the aircraft is just pulling left during your take off run plenty of right rudder should be enough to counter a turn to the left, however check that the geometry of your landing gear is correct, i.e. symmetrical and that one wheel is not binding. Also check the springing on your landing gear is not too soft/weak. Ensure that you have adequate flying speed before you rotate to take off, as if you unstick at too low an airspeed this will exacerbate your torque roll. A little more airspeed before you rotate will give you more rudder authority. Just my 2p worth.

Mike, yes the MPX BL motor 'Power Sets', as they call them, are eye wateringly expensive. No doubt very good quality but not great value in my view. See my previous post. Two motors and ESCs for £29 plus postage from Hobby King or alternatively get the XP 2836 1100kv motors if you have enough prop clearance on the Twinstar. What dia prop can you fit without it striking the Fuz?

My suggested set up would probably pull sub 20A with a 7X4 prop, so about 200W each motor on a 3s LiPo. I would guess that the Twinstar would be almost ballistic on that compared with your brushed set up. You could try 8x4 props instead but you might need 30A ESCs. Alternatively a lower Kv motor might be more efficient but would need a larger prop and I don't know how much clearance you have between the props and the Fuz.

I think most people reading this thread would be asking, why are you sticking with a brushed set up, apart from it is what you have. BL motors will be more powerful, much lighter and will not lose power due to the commutator becoming blackened and pitted due to the excessive current (coz they don't have one). A BL set-up doesn't have to be expensive, This would be my suggestion although there are many suitable cheap bell type motors that would probably also do the job. This is the Turnigy Plush ESC I would use. So two ESCs plus two motors would cost about £29 plus postage. Not too bad? Alternatively 4-Max in the UK do a suggested set up for the Twinstar. You have already replaced the brushed motors, receiver and about to buy another ESC, Save yourself some money and go brush less is my 2p worth. Edited By Piers Bowlan on 25/04/2013 11:04:34 Edited By Piers Bowlan on 25/04/2013 11:11:38