freakyer

hey there,

background: i have flown model IC helicopters (when the hirobo shuttle and concept sr's where about) and given up for a few years - lots of beer and a child later i have return !! (yay!) So i know my way around most of the helicopter.

Problem 1:
I have recently baught a Jabo II - the head moves up and down about 5 or 6mm. If you simply hold the frame still and pull the head up and down it moves in the frame. On the dragonfly there is a cir-clip holding the mainshaft in place - there isnt one on my Jabo. The thing flies (well it did untill i piled into the ground a bit too fast !! ) but i was just wondering if this was normal or wether soemthing is broken - there is nothing obvious and i have taken it apart and put it back together without effect?

Problem 2:
My firend has a dragonfly - i have been tryig to trim it out for him but everytime it takes off it simply piles itself into the floor. It tips left and forward very quickly. This is definetly not normal - does anyone have any suggestions or have had this problem before and fixed it??

Thanks in advance.

oops

Problem 1.

Some helicopters are a bit loose there... Keep in mind where the mast will be when the blades generate lift.

You can get a collet to lock it if you like.

I don't know if it's normal for that model.

Problem 2.

Dragonfly's are very unstable. Especially on the ground and when not in trim.

Once you are near flying speed, jumping past the "hover" position is sometimes needed. Especially if you are not familiar with them.

Otherwise, just trim it by eye first, then trim for flight.

Hope this helps -

David

freakyer

Thanks for that.

The jabo seems fine as i mentioned - its quite a good little helicopter for the beginnner - i would recommend it over a dragonfly.

I would have to say the dragonfly is better built tho.

So the trick is to "throw it into the air" then

I've tried it (well i havent been violent with it but i have tried to get it off the deck a bit faster than i normally would) but it always seems to end-up on its side faster

Another thing i noticed on the dragonfly is that the roll left/right servo has more movement one way than the other - it appeares that the linkage and the top half of the swash plate touch when the servo is at just under full movement. (to make it go right) It has alot more left movement than right is this normal? (not that i would ever see it being a major problem but i can see how it would resitrcit it somewhat)

oops

It sounds correct, but mainly because at full trim, it should be set slightly to the right to counter tail thrust.

It sometimes looks wrong to me also, but is OK. Perhaps it's just me.

Of course, that doesn't mean it's all right on yours - I'm just voicing an opinion and might be talking about something else.

By the way, stock dragonfly (walkera ones anyway) servo's are REALLY bad. They are quite unstable when they hover. Keep that in mind when you fly at first -

Also, head speed is low to make things worse. I cut my blades trailing edge so that the blade is never more than 32mm wide - which improves performance a lot !

David

freakyer

Great, thanks for that, i'll have a play with it tonight/tomorrow and see what i can do.

If anyone else has anything useful to say i would appreciate it !!

credence

My Feedback: (2)

It may be worth checking to make sure your servos are moving in the proper directions. I had a friend come to me with the same problem with his Esky Honeybee, would also pile into the ground on takeoff, he had all his servos reversed, so when he thought he was pulling back, it turns out he was jamming the nose into fast forward flight .


When standing behind the helicopter, the swash plate should move in all the logical directions. Going right should tilt it right, going forward should tilt it forward, etc..

UKgroucho

Where abouts are you freakyer... I'm near Stratford Upon Avon - south of Birmingham. Done a fair bit of learning / hacking with small FP helis (they started as AeroHawks but are now franken-copters) so I think I've got a fair idea of what works and does not. If you're 'local' I'll happily take a look. Spending most of my flying crashing Trex's right now.

freakyer

Well i think we've sorted it thanks guys.

We basicly stripped it down and rebuilt it making sure all the bearing were clean and that none of the shafts were bent - we notice the tail assemly was very loose on the tail boom (some ptfe soon sorted that out!! - gotta love ptfe) and we rebalanced it and trimmed it - its alot better now - we still have the servo problem where it touches the swap plate at full right movement (without the trim set to full) but without a longer rod we can't correct that yet.

Just waiting for the training kit to be deleivered and that should be it.

Cool.