Geoff Goodwin

I bought a second hand heli and have spent the last month overhauling it to make sure it does not fall apart when running. It came with a JP Starter and a rigid (not one way) starter shaft.   I just could not get the engine to run.   I bought a one way hex drive today and used it. Wondering why it spun but did not turn the engine over, the penny dropped. Some twit (not this one!) had put the red/black banana plugs on the starter the wrong way round. One good reason why the engine didn't want to know!   A quick switch on the connections and away the engine went!   So my query is, when you have a twin cable with one core having a white stripe on it, does this designate a particular polarity? In my case the stripe lead is wired to a black plug.   And do I get a prize for not spotting the rotation error earlier? At least with a prop you can see it spin the wrong way!    

Josh,   No doubt you have this sorted by now, but since there is no short answer on CCPM mixing I would recommend sticking CCPM into your search engine and checking out some of the offerings. There are a number of useful articles when I had a look. I didn't try a refined search for any particular Heli, but again this could be useful so you know settings for learning and settings for 3D flying. In the end you will probably progress from one extreme to the other in stages to suit your comfort zone!

wlfk Whilst you are not wrong, I think relying on trim to correct any CG irregularity is not good practice. Getting the CG spot on is always a good way to start especially if you are new. Of course getting the rest of the set up "right" is equally important   The less "fight" the novice has to contend with, the better chance to succeed. For people who have progressed it becomes more a question of choice and how comfortable you are with the need to quickly trim out. Personally I'm old school and try to set all my models up so they fly true with zero trim or as near to it as possible!   With small models it seems more critical as well.   Don't get me wrong, as you get experienced you get to know what latitude to allow, but without seeing the model yourself, the best way is surely to advise on getting it right.   Josh is dead right that with the linkages / swash set up right you should not expect excessive trim. If the balance is good to it makes me think design could be an issue. After all some models fly better than others. In this instance and if Josh is new to the game it would be sensible to get the model checked over by some-one with more experience.   Edit: If trying to hover outside in a breeze you will need forward trim and possibly quite a lot, as the model is in fact flying forward as fast as the wind is blowing to hold position over the ground.

Joshua,   "so my idea of adding some holes there to try and combat the tail heavy condition of the stock Belt CP should really wait untill my piloting skills improve."   I hope you have balanced your helicopter to get the CG in the right place. If its tail heavy before take off it will most likely try to hover that way too!   I have never tried a Belt CP so I don't know if the condition is common even when all balanced up, but that's what happens on every other helicopter I have flown. 

Eric Interesting comment about them "more to give a visual clue".  I have never flown without them and wondered about that aspect. To be honest, I seriously doubt that is the main function and wondered how you came to form that view?   I have always found the visual aspect of Helicopters difficult to say the least. I can never recall any real help from trying to spot the fins when once in while I do something silly. My usual response to any orientation issues is to do something positive and watch carefully for the anticipated response. If it isn't what I expected then I do a very rapid re-evaluation of what the model's orientation is! - Actually not confined to Helis, but will openly admit to having occasional visual problems with a Heli where is is very rare with fixed wing.   I have been passed the "box" a number of time by fellows who have flown models (not helis) to a dot and have no clue how to get them back! - Not lost one yet, but one took nearly ten minutes to cruise back once, it was slow flying and downwind - Sorry I digress!

I believe Stefan has the nearest correct answer. They are generally there to provide stability in forward flight.   Since in 3D this is not desirable, sure take them off. I would be suprised if the heavily perforated ones you see do anything to aid stability. Tail fins are in fact a liability in rearward flight and another good reason for the 3D guys to take them off or put a load of holes in them!  The vertical fin often has a dual function in that it provides a skid to stop the tail rotor striking the ground.   Once you start taking the flight envelope to extremes, all manner of issues need to be considered to effect the desired level of stability or instability. So you start to get refinements you see on full size, especially those for use in combat where instability tends to equate to quicker response.   So back to Joshua's question, I think he already had a grasp of what they really do and wlfk is also right about achieving a balance in the performance that suits the purpose. Really in general terms no right or wrong to them, your choice in the end is to get the performance that suits your particular need.   Since 3D is not my cup of tea however impresssive it looks I will retain solid fins and enjoy more relaxed helicopter flying complete with Gyro of course

Thanks for the posts Gents. Side tracking to onboard glow systems Has anyone simply used a micro switch linked to the throttle servo? So it is physically switched in at a low throttle setting? I was thinking of using a cam against a micro switch arm so travel length is not an issue and is also adjustable. Edit: Perhaps even a micro toggle switch so you can kill or liven the circuit. You know like the "contact" switch on the side of a tiger moth!

I have just got my first fourstroke, secondhand. One model I would like to fit it in would look better if I could fit it inverted instead of side mounted. Upright is not an option in this case. So my question is, are these motors OK to run inverted ? I would not ask if I was fitting a twostroke but thought, if in doubt, why not ask the forum!

Try this http://www.futaba-rc.com/manuals/manual-6exa.html

I am not sure what you are trying to do. If you are wanting flaps on the same control surfaces as the ailerons then flaperons are the way to go. I assume you have servos in the wing on the underside so the following would apply. If you want just simple differential movement then no mixing is required as this can be done by simple geometry! For more up than down the arm on the servo needs to be raked forward (towards the aircraft nose) when in the neutral position. When the arm sweeps forward to apply down it will travel more through the curve and give less movement on the control surface. The reverse is true when you apply opposite stick. You can still mix with flaps if you really want to. OK so maybe some sets can do this electronically but I come from the days when you had to do this the hard way  I do not recall differential movement being an option on my EXA but the manual for your particular set is the place to go to check.

As some-one who has just started in Electric power this has been a most informative thread on the one bit I have hated about electrics so far - i.e. Going live (armed) before you can finish rigging. I'm not sure if you can upload images to the forum, but would be interested to see how the solutions referred to look in practice. It got me thinking about a small arming hatch that could be as small as a tube with bullet type connections inside and a cap to close off the hatch - naturally you would need some cable slack to allow sliding out to connect / disconnect. Is there any reason why this would not work or otherwise not a wise move?

Garry, Nope by comparison I'm the sping chicken! You were in your teens when I made my first appearance. What you don't know is I have been flying models for almost as long as I can remember. I don't think I was even in my teens even when I built ,my first valve radio from a kit - I still remember the 135V DC shock or two I got fiddling with it live! - I recall it seemed to have a bit more kick than 240V AC. Perhaps it was not the 135V from the two 67.5V batteries (in series) but some part of the circuit amplified for the valve. I certainly didn't understand how it worked, just how it was supposed to go together. The receiver kit was one step up from its valve predecessor as it had a transistor(s) instead. I will be starting to ask a few questions shortly - like "who was the bright spark that decided a Red diode on a futaba 7C transmitter was a good idea to show it was switched on!" - I spent ages trawling through the manual trying to find if it was indicating a fault! Cheers Geoff

G'morning all, well it is as I write, being something of an Owl rather than a Lark! Not so much a  newbie as an new old timer. I padded out my profile with some background so those in the know might even be able to guess my age or near to it. After more than a few years out of the this area of aviation I have a decided to get back into it so hopefully my Son will take an interest. You can have a laugh when I say I have kicked off by getting a small 3D electric helicopter. Truth is I have been through about ten charges on this and now happy with a hover in the Dining Room so it's off to the some-where with some space to expand the envelope. I learnt long ago that careful setting up and adustment takes the hard work out of flying and my first few sessions with the Helicopter were dedicated to adjustments until it could take off and hold a hover with my eletronic trims all on Zero and just a nudge here and there on the stick to hold it in the limited airspace.  I have also bought a 2m electric powered glider with full house functions. I hope to see how the lad gets on with it once I have it set up. This model is for me, but if he can keep it in the air and takes an interest, I will get another 3 channel one for him to learn on properly  before progressing to non-gliders. Because this re-start of my hobby is going to be mainly electric I have decide to go for 2.4Ghz gear but not used it yet! I will use the trainer lead to link the 35Mhz I am currently using to the 2.4Ghz Tx. All futaba square pin, so no problems anticipated. It seems there is simply mass's of information to take on in the electric power field and I look forward to getting a fuller understanding though the forums and clubs. I have my enquiries out with the local clubs and should be doing the rounds when the conditions are right to see which I would like fly with (if they will have me of course!). That's about it for now - time to hit the sack. 

Like yourself, I've decided to actively take part in the hobby again after a long break. However i did some digging on the Futaba gear before buying some new (figure my M series is best for the museum now!). I'm going to invest in a parkflyer type model to see if I can get my son interested. However the key points when selecting the model will be. It needs to be slowish and stable so it's not a fight to fly. It needs to be practical and easy to repair. One way or another it will have to take a rough landing or two! As I want to use futaba gear as well, I will not bother with a pre-existing radio equiped model - what's the point if you are going to rip it out? Some of them have servos that would not be compatible with your futaba anyway.  If you bought a full futaba set it will not really suit a lightweight parkflyer. You will need a lightweight receiver and some half decent micro servos. With electric powered models, a reciever with good interferance rejection would be a good idea. I think pcm is probably better than ppm. In my case I selected a R146iP futaba receiver. It has pcm and uses single conversion crystals and is working nicely in a 3D heli I jumped back into RC with! (Modern Heli actually easier to fly than the .19 powered MM Lark I learnt on!) Back to planes though, I will start with a small, simple, electric motor powered glider. Once my son gets the hang of it I can progress him to someting faster and less stable perhaps a piper cub type although a trike might be better if it is going to have wheels! Thing is, avoid jumping in with something you can't cope with or you might pack it in again too soon. Getting a trainer to help you is first class and will allow you to tackle something that otherwise you would never cope with. However, learning to land the model safely could be really hard work if it needs a lot of flying to keep it in position. You can get away with almost anything in the air but even a trainer will not be able to help you if the landings are too hard to get to grips with. How good you were before you packed it in before should be a guide of what you will cope with now.  I used to fly just about anything and train a few along the way. I know my reactions will not be as instinctive as they were, so that electric powered spitfire can wait until I sharpen up my response!

Sorry everyone but you know a newbie is bound to win it!