RC Planes

Just check it with moving rudder on transmitter, fully left then right, if it does just reduce travel a little bit with your settings on Tx, there are other ways of reducing travel, ie changing holes that the clevises go on on be it rudder, aileron or at the servo end. You won't need a great deal of travel on any control surfaces on that model anyhow.

You will be surprised at how little travel/ movement you need to alter flight
 
To check for binding put full right rudder and whilst holding it give it full elevator up and down and then repeat for full left rudder.

With long push rods, they tend to flex inside the fuselage when pushing so you get less movement than pulling. You might be able to hear/see it moving if you have a look whilst operating the servos.

Various fixes I've done in the past are to glue the push rod sleeve to the side of the fuselage, change the push rods to carbon (or balsa wood) spars with the metal links at the ends. Change the set up to a pull/pull link. Or most drastically, relocate the servos to the tail/rear of the fuselage and have direct links.
 
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Thanks guys.

I thought it might be the metal bending - I'll have to check out getting a carbon spar to stop it flexing. I could mount a servo at the end, but if it's external it'd look a mess and if it's internal it would mean cutting the fuselage. I'd probably royally screw it up.

Pull-pull would be a good idea. I have enough servos - 4 on the plane and another 6 (people were moaning in the reviews that they're rubbish so I bought enough to replace them all... now I'm thinking that was a little excessive :o), so I could always beef the rudder up with another long spar thingy.

Also because I have a load of servos spare I can set the flaps up! Woop. I was thinking I'll need a y-connector in the future as they'll eat up another 2 channels. 5 channels with the individual ailerons and another 2 for the flaps. I could really cut it down to 4 channels inc. ailerons and 5 with flaps, I guess? Is there any need to keep the channels down to a minimum? Probably not?

My 2nd order arrived today, the extra batteries. Now I've have 6 x 2200mah 3s batteries and the right connectors to charge them. Whey. :cool: :p
 
The pushrods will just flex and it's normal, it should fly just fine. I only did the modifications because I was flying acrobatics and felt I should. That and I was bored one weekend!

Pull/pull still uses the same number of servos, you just use both sides of the servo arm and a control horn on each side of the surface.

If I was you I would make sure the control surfaces are responding correctly, are centred at rest, charge the batteries and then go and find a field with some long grass. :)
 
Has anyone made any 3d printed RC planes? I am just wondering as I might start saving for a 3d printer. I might turn into a business by selling cheap frames for quadcopters etc.
 
I wouldn't worry too much about flex, this is your first plane right? So you won't exactly be doing anything too taxing on the control surfaces. If I was you I'd just get flying, then if you find issues then you can look into sorting it. At least you will be able to get plenty of flying time.

Don't worry about reducing your number of channels, plus I would be very surprised if you really required flaps. If you use separate aileron servos then you could go for flaperons, though it does reduce max deflection when you are using the flap feature.
 
Alex - you need a bend in your pushrod, that is going to bind and probably burn out the servo after a while.

just do this with it:

23wsne1.jpg
 
Yes saitrix, first plane. Just can't stop faffing about with it. :p

I won't bother farting around with the rudder any longer, though maybe I can go down the pull/pull route later on - didn't twig you could do that. That's what the double ended servo arms are for... yaa.

One thing I would like to know is if it's possible to reset the servo so that it only goes in one direction - like full travel in one direction, and not half travel either way, if that makes sense.

I have gone and started putting flaps in (:o), and the distance is only the same as the ailerons. I'm thinking as they'll only be working in one direction, I could set the servo to have maximum throw in just pushing the flaps down. Is that possible? Is it on the transmitter, or on the servo somehow?

Also I need to reflash the 9x as the firmware is different to the guy in the youtube video I posted a while back. His version looks much better and I can't understand what he's doing on his as mine is different in a couple of key areas. I want to be able to put the flaps on a switch, for example, but it's different when he does it.
 
You can't set the servo, it's all done in the radio.
Flaps and gear channels go from -100 to +100 (think of the servo turning all the way to the left as -100 and all the way to the right as +100) so instead of centering your servo, you set it to full one way and the put the arm on and centre the control surface.
Then when you hit the switch the servo moves all the way across it's range and the flaps drop.

In reality you set the endpoint on the channel to something a bit more sensible (like -20, +80 but your model will vary) so that the flaps in one position are at centre and when you flick the switch they drop and you don't hit anything or stall the servo.
You can adjust the linkages from the servo to the control horn to give you more or less movement, but you still need to tell the servo not to move in one direction.

Of course you may have to add some mixes to the elevator channel when you drop the flaps as the plane can do funny things when you drop them.

I still think you should try flying it as it comes, you may find flaps are more trouble than they are worth. I've only really used flaps on my glider, that and crow breaking to stop the thing gliding off down the field when I want to land!
 
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I can't say I have ever used flaps, I really don't feel that much of a need for them. If you plan ahead you can get planes slowed down enough, especially something like a trainer plane.

Seriously just get flying. :p Just have a look at done two small bends in the elevator pushrod and in my opinion it's all good. Though do make sure your CG is where it should be, having it out is a sure way to make a plane a pig to fly.

I also need to pull my finger out and get flying again, haven't done it for a few years! Will have to check out my batteries first, then I know I want to swap over to 2.4ghz as its nice not worrying about crystals.
 
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Ha, depending on how today goes that might be all I'm capable of doing. :p

Sorted the centre of gravity today. Securing the battery inside was a bit of an arse, to get right balance I need two 2200mah batteries, but mounted a few inches from the end of the nose. One battery left it massively tail happy.

Everything seems to be sorted now, got everything looking straight so now it's time to give it a go. Let's see how many times I crash it...
 
I'd worry about the rapidly increasing weight too, you don't want to be flying with 2 packs if you can help it, will increase your stall speed.
 
Well had an hour piddling about earlier and had some really good flights!

The centre of gravity thing with just one battery would not work, the wings were set up asthey should be but one battery wasn't heavy enough to bring the nose past horizontal. Two batteries were better, but I then spent ages trying to sort out the balance with those. Had to strap then together with tape the use Velcro to position them just-so.

Many launches ended up with me just throwing it into the floor. Perhaps because of the extra weight, and the motor going dodgy - explain in a sec - it didn't have an awful lot of power to get going. The motor ended up dismounting itself from the plane JUST as I was landing!! I'll put up photos tomorrow but it completely left the mount. :D Prior to that though it was weaving about in it's mount and made progressively more noise until it finally exited the plane lol.

Otherwise it flew pretty damn well to be honest. I only used the two batteries, not sure how much, but it didnt falter - though when doing a huge dive from way high up it refused to react properly. Would it have been the servos not being able to provide enough force? Was a bit scary, would've really smashed it up at one point if it weren't for a gust of wind to blow it level again. :p

Very cool though. Proper chuffed. :)
 
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At least it is all in one piece still! That's a bit useless with the motor mount to be honest, I wouldn't be that pleased with the plane being brand new.

With the none responding input, if you still had other inputs working then it is either the servo or linkage at fault. In the end you may want to just sort both out in one go.
 
Yeah taking off into wind. First couple of times I didn't though. :p

Here's a video of me actually launching it properly - this was preceded by me throwing it into the floor 5 times in a row:


Fixed the new 2212-06 motor to it last night. The mount itself is actually OK, but a little pin or screw that held the motor in disappeared and meant the motor just exited at the back. The new motor has MUCH more thrust - almost ridiculously so - the sound it makes when revving is just insane. :cool:

2212-06 motor:

 
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