700N Vbar Silverline unstable flight and tail wag...

[Delarado]

I have the silverline Vbar on my 700N, and every now and then it seems to go a bit loopy.

On hard pitch manouvers (Rainbows etc) sometimes the tail wags violently. It can be during the pitch, or 5-6 wags on transition from positive to negative pitch or vice versa. No wagging in fast forward flight. Is my gain too high?

Also, sometimes it seems to roll a bit all on its own. I particularly notice it during autos.10-20 degrees of uncommanded aileron roll from time to time. Is my gain too low on the cyclic?

Don't have any issues like this on my goblin or on my 700E and the setups are pretty much the same as far as gain/agility values go.

Any ideas? I've not checked vibes just yet, is that the best place to start?

[waveydavey]

Engine vibes and mounting tape on sensor. Try a harder tape Carl

[Delarado]

I'm using the tape that came with the vbar. It seems quite soft. I have some stiffer stuff, I'll give that a go, thanks. Do you strap yours down? mine is.

[Matt_W]

700N Vbar Silverline unstable flight and tail wag...

I had the same trouble, it turned out to be bearings, check the main shaft bearing first.

[Delarado]

come to think of it, it does sound a bit noisy now youve said that matt! Its only done about 15 flights though... I'll check it anyway.

[waveydavey]

I don't strap either the V Bar or BeastX down. I use a hardish tape from Maplins and haven't had the problem. Good call on the bearings, although I would expect a bit more than 15 flights

[Matt_W]

700N Vbar Silverline unstable flight and tail wag...

I have got through so many, I have been thinking about upgrading to the lynx bearing block.

[tonystevens]

Have you pinned your boom supports? loose ends can wreak havoc with the 700 and are not always obviously loose, undo them and check for any movement.

[Geek]

700N Vbar Silverline unstable flight and tail wag...

Is it engine gov causing it?

[Delarado]

700N Vbar Silverline unstable flight and tail wag...

How do you mean pinned them tony?

I don't thin it's the gov? The wag is very fast like you'd get on an electric Heli running really high gain...

[tonystevens]

How do you mean pinned them tony?

I don't thin it's the gov? The wag is very fast like you'd get on an electric Heli running really high gain...

The stock supports are pants and need pinning to stop them coming loose. The way i do them is to drill a 1.5mm hole through the plastic ends (where it says align) and put an M2x16mm caphead bolt through and a nylock nut on the back. Ill bet if yours are stock they will be loose. Take them off and check them, any movement whatsoever will cause the tail to vibrate amongst other things.

[Delarado]

Funnily enough Tony I just gave them a twiddle on the way to bed. You can definately feel that one of them is loose at the frame end (As opposed to tail) as I can rotate the rod by a little bit.

Do they really cause these sorts of issues? There's barely any movement in it!

I will pin it but I'm interested if you had the same experience as me? My old 700E had a brace halfway up the supports but this one does not. do you think that may also help?

[coolice]

Hey Carl.

Can I look at your Vbar log please? This might give us a better indication if there is an engine vibration or other causing your problems.
.

[jimmyhorns]

I don't strap either the V Bar or BeastX down. I use a hardish tape from Maplins and haven't had the problem. Good call on the bearings, although I would expect a bit more than 15 flights

Which tape please?...

[Delarado]

Ill try and get it off Ian, not done it before! itll be later in the week now before i get chance! working away in nottingham beginning of this week.