SCALE MATTERS

[Ernie]

Hi Guys

Why is there so little interest in the new SCALE MATTERS topic?  How sad it is, does no one, except for a talented few, actually build models anymore. Are the building skills being lost for ever? Are you all planning to spend the long winter evenings in front of the tele and the PC, instead of fettling the balsa?       I say, twice the fun if you've built it, trice (is that a word) if you've designed it as well.  Sorry, I'm not saying anything about breaking it 

ernie

[flytilbroke]

The scale entusiasts I know tend not to spend a lot of time on forums. Too busy with thier scale creations, so focus thier attention on specific to them, subjects.

I have started balsa bashing after a fifty+ year lapse, very time consuming, though I am enjoying it. Stopped watching any Tv for the last couple of months too.

 Enjoy.

[Rob Cope]

Yeah,

I'm a newbie and I'm trying to build the nexus plans Handley Page Halifax. I find the wing span is too long and the fuselage height 1/2" too big (based on fuselage length which seems to let it off as "close" on most measurements.)

I'm a bit flummoxed by this. Not that I mind spending £15 on a non-scale plan, but how to right the wrongs in terms of the parts I've already cut and knowing whether a proper 1/15th scale plane will fly with 4 Saito FA30S engines turning (almost) scale 3-blade Graupner 9x6 props, and will it be able to fly slowly enough (14mph!) to do scale passes???

Regards, Rob

[Evan Pimm]

Rob, there's probably nothing you can do at this point other than starting again, with a known accurate drawing of your chosen version and redrawing the plan with the correct outlines and sections. Any 1/15th scale four engined bomber will not be able to fly at 14 mph unless it is really light, and the four Saitos are already too heavy. You might be able to get it to do scale speeds at 1/6th scale, but the same admonishon applys. I really think you need to re-think the whole thing and perhaps lower you expectations, then build up over a series of designs until you have the knowledge and expertise to accomplish this task.

Evan. 

[Ernie]

Hi Rob, Evan Pimm is right. Start with something simple, or you are heading for big (really big) trouble..If your Halifax ever is completed , who is going to fly it? Certainly not you. Maybe a few years down the line...A great scalish trainer is the Flair Cub. You can dress it up in all sorts of civilian and WW2 colours, and its a great flyer. Please put your dream project on the backseat for  a while..Join a club, talk to the lads, they will certainly reinforce the above

ernie

[christopher small]

I am building a Sig Models 1/4 scale Piper Cub,I don`t have much spare time at the moment,but getting on slowly very slowly,but some progress is better than none.

I have a Magnum 4 stroke ready to go on as soon as poss.

Chris

[flytilbroke]

Jetsome asks,,,, What am I knocking up just now? The following is not the answer I would have given twenty years ago

What am I building? Not as yet anything like scale, a Northstar. Slow going as I am learning how to correct mistakes,  not the most basic one though. I did not make a jig and it's fuselage got a little banana shaped. I have taken lots of photo's as I finish stages with the thought that I might add the story to the forum.

Been doing some more serious repairs to other models too. All part of the learning process. Next build will be after a Travelair recovering, I received it in damaged conditon from another modeler, I have repaired it.

 The big box of balsa for the next build is supposed to turn into a Mosquito, so it is likely I will finish it to look something like one from a training squadron. But first,,, ARTF time, an Extra 300 which I got from Falcon Models at Woodvale.

[Former Member]

[This posting has been removed]

[Bob Cotsford]

flytilbroke - I love looks of the Northstar, one of these days I'll get myhands on a plan or kit....

Meanwhile, my Don Stothers' Bucker Jungmeister  just needs the UC and cowl fitting, struts making and a bit of rigging wire, my CAP Gladiator is waiting on the lower wing covering, struts, rigging, markings, radio and exhaust system.  Not very scale, most definitely 'stand-off' - the further the better.

[Danny Fenton]

Hi Guys, Ernie I think the guys are right, the scale guys know what they want and just beaver away. The problem is it is hard to find out information from those talented people when you are starting out. I am doing a 3/4 scale (55") Brian Taylor Hurricane, before starting a normal sized BT Hurri as the winter project. I posted some questions about taking part in scale competitions but never got any answers. The Clubman class at the Nationals had 4 entries this year. I am sure there would be more if information were more freely available.

Its not just on this forum that scale questions go unanswered, its the same on others as well.

Danny

[Andrew Thomson]

Hi ,

     I would suggest that you contact the BMFA directly re queries on taking part in competitions. Use the contact numbers in your monthly bmfa news.

     On the topic of scale , there are the serious afficionados , for whom absolute detail and competition will only suffice , all the way down to the "profile" modeller . Most of us start at the "profile" end and slowly progress towards the other end over the years , adding more scale features and finishes to seemingly ever larger models along the way , interspersed between the odd fun-fly or other sport model . There is also the need to perfect one's flying ability in order to succesfully handle the increasingly scale models that emerge from the shed . It almost seems inevitable that when people say scale they mean some form of ww2 warbird . This was what they always wanted to build and fly - usually regardless of their ability to build or fly ! In some cases the semi-scale artfs around can get round the former and simplify the second to an acceptable degree and provided there is some flying skill evident , can lead to succesful repeated flying without mishap. One cannot however escape the fact that as warbirds go , the more true to scale they are the greater the difficulty in flying. This is because they were designed to be inherently unstable to be able to change direction in an instant . This tendency can be overcome by increasing size and reducing wing loadings , but once you go over 60 / 70 inches even that starts to present its' own problems of cost / materials / engine size etc.

The journey through to a good 60+ inch warbird for the club field that looks the part without too much detail being needed should not be rushed . To go there too early , with a poorly built or finished model that crashes first or second time out will be so dispiriting , not to mention expensive. Ideally do not even consider a scale warbird until a good year after passing your A certificate and having built at least 2 or 3 models from plans only. The process could be speeded up by building more suitable scale subjects such as high wing cabin cruisers such as the Auster aop9 , Piper Cub , first . The flair semi scale biplane series are very good as an early starter. Scale models can be very satisfying at purely non competition club level. Whatever you go for - enjoy it.

[Rob Cope]

Okay, Thanks Evan, Ernie, Eric, ... I misled you all a bit. I'm not a newbie to flying - and yes I've made the same mistake on other forums - I'm a newbie to building scale. More like an experienced novice or beginner with R/C flying. I have been flying about once every week on average since March 2007. I've got a boomerang trainer with an Irvine 53 in it and boy does it go?!! The GPS I sometimes put inside it (yeah, I know, I know, but it carries it OK) says it does between 60 and 90 MPH and 30 for landing. I've bought a second-hand 64" spit with a TT GP-61 and I'm flying that too (when the engine will run!!!) re-tank needed I think. Anyway.... I'm not trying to build an exact scale aeroplane, but I will be the one who looks at it most, so I want the dimensions pretty well right, aerials and intakes/coolers/eternals correct too. As for the right guns and cockpit detailing, I'm not concerned. I probably won't even put personnel in there. However, I wondered how I was going to get 14 MPH out of this crate? Obviously not - it was a devilish question. As you rightly say, I'll just have to go as slowly as is safe and put up with that. Not all of us, even_with_ four-wheeled transport can shift a 1/6 scale Halifax around!!! You'd need a large van or a flatbed lorry... I'm limited to a big-ish hatchback and I don't fancy a four-piece wing and two-part fuselage! So, 1/15th it is. I reckon by the time this monster is built (maybe not even in time for 2008) I'll have plenty of experience on the low-wing spitfire. Using Saitos and running them in, in advance on lumps of wood on a hillside, I should avoid too much engine trouble. So I think it's... yes, a bit early to build my dream plane, but not so early that it's ridiculous. I see many ARF almost scale modern sport models and, sadly, they do little for me as I'm not familiar with the originals and they're all quite similar in my opinion... Little character. Maybe I'm spellbound, but I like the unpolished appearance of the HPH, especially the less-warlike MK III GR II met plane in white and grey - very different from anything else around, and stylish in its own way. Plus it has the appeal/nightmare of four engines and (almost) retracting undercarriage... if I can manage to make some! Regards, Rob

[Andrew Thomson]

Dear Rob ,

                 Forgive me but I think your wonderful enthusiasm is getting you a little ahead of where you safely ought to be. Have you passed your A certificate yet ? This ought to be your first goal . To safely fly a twin upwards I would suggest you should be ready to take your B certificate first.

                 From your description , you are having trouble with the smooth running of your TT61 in your Spit. Please , do not even think about flying a twin upwards until you can reliably and perfectly set up an engine for repeated consistent performance. There have been some good articles on setting up engines in the mags . Essentially , get it running , open to full throttle and adjust the main needle for max revs ( go slightly rich if a new engine ) , once this has been set then the second needle or screw should be adjusted 1/4 to 1/8 turn at a time until you get a smooth transition from idle to full power when opening the throttle . Once set , leave it alone ! only minor adjustments on the main needle should be required occasionally according to atmospherics. If you constantly need to mess with it then something is wrong - or you have caught meddle itus !

                One aspect of flying twins upwards that you will not have experienced is what happens if an engine cuts and you turn the wrong way or too sharply - catastrophe !!! and with a big model being out of control in a terminal dive , it could kill someone.

              You are perfectly right about the level of detail - only put on enough to satisfy yourself . You will increase this over time as you learn new tricks .

            Flying a twin is a very demanding task and handling one with a dead engine requires an expert - and sometimes that is not enough ! The best advice would be to shut all engines down in the event of one failing and land deadstick as best you can - although you need to take rapid account of all circumstances at the time.

           Before you build such a model , build and fly a smaller , simpler sport or scale model with say twin .25's for experience . Talk to the more experienced members in the club for their advice . Check out the LMA website and shows etc , talk to the experts in flying multi-engined monsters and get their invaluable advice.

          Sorry if this sounds a bit condescending - I don't mean it to be . I just want you to enjoy the process through to your  dream model , for it to be succesful and safe for all around. There is a lot of satisfaction to be had in all the necessary preparation steps , good luck.

[Danny Fenton]

If you want to take some of the sting out of twins, do it electric. Good quality IC motors can be expensive, and to get the reliability needed they need to be good engines! With the arrival of good cheap Brushless motors, powerful and robust A123 cells, multi engine is a lot easier electric.  Mind you saying that I heard John Ranson (100" electric Hornet) even managed to stop just one engine during a flight, something to do with a very, very, low fly past

[Andrew Thomson]

Fortunately you don't get quite the same reaction with electric motors and the model landed ok on one motor. He had touched the ground with one of the props and somehow this had put it out of sync with the esc !? Having disconnected and reconnected all was ok apparently.

The only problem with going electric is that you will have to become some sort of electrical engineer to understand the powerplants and batteries and how to treat them etc.This is not to mention the medium fortune it will cost you to buy all the gear and then new li-pos batteries  etc. Without an expensive but very effective sound system being built in , any electric model just does not "live" , it sounds all wrong - quiet and all wrong . However , having said all of that , if ever there was a use for suitable electric power it would be in multi-engined planes , if you are good enough at elecktrikery and wealthy enough to afford it !

[Danny Fenton]

Hi Andrew, my heart sinks when I see how much people spend on electric flight, you don't have to....

e.g.

YT Hurricane - 70" 11lbs

£40 - Sentilon 100A 2-12S speed controller

£84 - 12 A123 cells £7 each

£22 - TP 5330-8T 2.9KW max

£19.99 - Laptop PSU/charger, £19.99 from Ebay...

Can you  buy a 120 sized IC and fuel for  £165??

the only other thing you wil need is a balancer such as the Astro A123 Blinky balancer to balance your cells every half dozen charges or so.

Electric flight is down to ohms law and is not so difficult, P=IV, power equals Current times Volts. Get a wattmeter, and follow some simple rules and it is not so difficult, and also not so expensive.

I had never flown electric until this spring, If I can figure it out anyone can.

Danny

[Rob Cope]

Thanks All,

I am an electronics engineer BSc Hons (3rd grade).  I know electric planes are _very_ handy for those "who have invested" and there are some wonderful small cheap airframes out there just waiting for a motor or two and ESC and cells, as well as the constant possibility of converting most (if not all - these days) I/C airframes to electric.

I simply prefer I/C.  I'm not knocking electric.  To me burning fuel is what an aeroplane is all about - (some) noise, petrol/methanol and power.  I know it's environmentally unfriendly and that electric planes can be powerful too - and very fast, some of these light-weights are amazing - but they just don't compare in my heart with the "real thing!"

Anyway, I know I'm biting off a whole lump that's rather big to chew.  If I get an engine failure, I'll throttle way down and coast in - as per A-cert dead stick single-engine practice - and land wherever I can given the height and wind direction.  I have been told I'm ready for the A-cert.  It's just the book-work that has stopped me doing it already.

I know the Halifax is a risk, but so was progressing from a trainer to a spit with a faulty engine (albeit ARF and with fat wings and a shocking dihedral) but I made it (right leg in repair at present - retract shell split!) and I rather fancy throwing some money at this Halibag and just "having a go." 

I am very lucky in that we have expert guides at my club and safety is a very important part of our flying scheme, so I'm sure everything that can be done will be done for the first few flights to ensure everything is safe.  Otherwise I'm certain the guys will call me back and tell me to "stop those engines and wait young man!"  That's if I still qualify on that score....

Later I can even under-fill a tank and try out the engine-failure procedure at a safe height and good distance to see how it goes first time.

Regards, Rob

[Andrew Thomson]

Hi Danny ,

                Glad you find electric power simple to understand and the models satisfying enough to fly . Very few I know in 3 clubs do I'm afraid. As for a 120 and some fuel for £165 - no problem , also no lengthy delay between flights (re-fuel vs recharge) and long term a much lower running cost  , plus it sounds lots better unless you have a fancy sound system with the original sound - I've heard these are tremendous !

Each to their own ! I must admit though , if I were to build a multi then I would have to consider electric power from a safety viewpoint .

Andy.

[Andrew Thomson]

Hi Rob ,

             Well said re a model having to live and burn fuel , couldn't agree more . I also have nothing against electric power in it's limited place . I just cannot stand those who "evangelise" about it as if it is something desireable and we should all be doing it for the sake of it , as a more desireable option to a real engine! For me , and many others including Mr Boddington ( judging by recent scribing ) Electric power is a technological marvel , but just a poor substitute for the real thing , to be used only when absolutely necessary.

            Don't knock the fat wings (greater lift) or the "shocking" dihedral (greater stability) of your artf Spit . It is these features that make it more controlable than a full scale version . If you fancy a much more scale version that flies well on a .61 then build yourself a 63 inch Spit from Mick Reeves - see his website for details.

Would definitely recommend the LMA (large model association) for info and guidance on your favoured project though - good bunch of lads only too pleased to help.

Andy.

[Rob Cope]

Thanks Andy!

A voice of moderation in a world of extremes! No, I jest,but it's nice to hear a measured response. I was assuming people would realise I meant it wasn't a "real spit" from the "dihedral and fat wings" comments - rather putting down my ascendency from trainer to spit you see - a bit of joshy self-denegration!

I'll look up both your references. Thanks very much for the help.

Regards, Rob

[A.A. Barry]

Hi guys, (persons), how about some answers to some the scale problems, eg how do you constuct a sliding canopy, where do you obtain the "bits", likewise, the geometery of a retract gear, some of us away from the mainstream of modelers, do not get the chance even to see a "pro" built scale model, I am sure that there is a lot who know, but we need to pass this "info " on to our young ones, or there won't be any "balsa bashers" left, lets put  put the "hard word" on the  "boss" and see if  a page or two in our fav. mag can help and inspire, how great it is to construct your own model, not buy it in a plastic form. I await some further commet ,Yea ....... Regards Barry    

[Danny Fenton]

I agree totally Barry, it has taken me ages to work out undercarriage pintle angles to make undercarriages that retract such that the doors are parralel to the airflow when down and lie flat with the wing when retracted. Really simple once you know how, bet theres loads of modellers that would like advice like that, you could also add something on resin casting exhausts etc.

cheers

Danny

[A.A. Barry]

Thanks danny , NOW let's get some more of US to rally to the cause, Regards barry

[Ernie]

Hi Barry and Danny

I totally agree. An exchange of ideas and information is what is needed.

Re Danny's casting of exhausts, try an artists suppliers called Tiranti, a veritable Alladin's cave of modelling bits. www.tiranti.co.uk    Among other things, they sell silicone rubber moulding materials.   I build a wee box from lego, make a male prototype, and cast a female master mould.  The exhausts, etc can then be cast from resin, maybe with metallic powder added, to give a nice finish. It works a treat, the silicone is flexible enough to allow a bit of undercutting.  More details if you wish.

Now, can anyone help me with wing warping?

ernie

[Danny Fenton]

Hi Ernie, already have some of the supplies from Tiranti, arrived this morning LOL molding silicone rubber and resin, will see how it goes what do you make your patterns/masters from?

 Wing warping is easy, stopping them warping is another thing