do helis naturaly vibrate?

[dieselcarb]

hi there sorry for the dumb question but my heli has an ever so slight wobble/vibration it has new main bearings,main shaft and feathering shaft new rubber bushes and flybar and blades i tried a new head (cheep 1) and that wobbled bad no then put my good head on that is also brand new that has i dentical vibration

now is this slight vibration normal ? or should the whole heli be totaly vibe free?

thanks i just want it to be perfect for friday as evo andy on here is helping teach me set it up

thanks terry

[LaurenceGough]

A heli will always have slight vibrations but these are very minor and will not effect anything.

If you can see vibrations most often that is too much.

Have you checked both the main blades and tail blades on a 0.00g scale?

[dieselcarb]

no but i did ballance them on a seesaw balancer thingy not got any decent scales but mabe its time to get some cheers

tel

[LaurenceGough]

They should work fine they are just more tempermental than scales. I've seen a few blades end up worse than out of the packet when balanced with them (you can always try removing your balancing tape first).

When adding tape add it to the COG of the blade (balance it to the tipping point on a round rod straight and add tape there).

Also check your tail shaft for straightness.

What heli is this and what can you see vibrating?

[dieselcarb]

the vibrations can be seen just about on slow head speed touch the tailfin and theres some vibration i assume its naturall but if it not then im stumpped spent hours toyin with it but then it is a heli lol cant realy see the vibes when on full spin

[unwind-protect]

no but i did ballance them on a seesaw balancer thingy not got any decent scales but mabe its time to get some cheers

Seesaw balancers are very accurate when used carefully; first apply tape to the tips/ roots to move the centre of gravity to the same point, then apply tape at the centre of gravity to balance the blades.

[dieselcarb]

its a clone 450 made by titan the head looks fine once spinning and the tail looks fine but i will change it now u mention it as it may of struck ground ant its just a small vibe on tail boom

[dieselcarb]

Seesaw balancers are very accurate when used carefully; first apply tape to the tips/ roots to move the centre of gravity to the same point, then apply tape at the centre of gravity to balance the blades.

now we are talking i will give that a try also model shop didnt say any thing wrong with blades but i just put a sticker on 1 blade as they wernt far off perfect out the packet but never checked cog

[cjcj1949]

Everything vibrates a bit. That's what happens if you have what is called a mass spring system. There is a natural frequency that things will vibrate at. As you spool up you can find that the frequency from the rotor is the same as the natual one and this results in lots of vibration. If you spool up faster it will go away. Your vibration may be normal or due to something out of balance or loose or some dodgy rubber bits. It is the sort of thing that needs to be looked at by someone with experience and is part of setting up. So I'd wait for the man.

[LaurenceGough]

COG blade balance is so close these days I do not even compare the blades - I used to but it made no difference. Either way it can't hurt to check, especially on the cheaper blades.


Make sure your head hub clamps fully to the main shaft with no wobbling.


If it's only vibrating on spool up or on the ground that's normal if it doesn't in the air, nothing to worry about.


On another note if it's a whole helicopter wobble/vibration in the air then your headspeed may be too low, sounds like it goes away when you have the blades going faster?

[dieselcarb]

COG blade balance is so close these days I do not even compare the blades - I used to but it made no difference. Either way it can't hurt to check, especially on the cheaper blades.


Make sure your head hub clamps fully to the main shaft with no wobbling.



If it's only vibrating on spool up or on the ground that's normal if it doesn't in the air, nothing to worry about.


On another note if it's a whole helicopter wobble/vibration in the air then your headspeed may be too low, sounds like it goes away when you have the blades going faster?

i think this might be it head was wobbling so thrown it out but new heads fine but what u wrote sounds spot on wbble on initial spool up i.e as motor kicks in then smoothes out although not had in air yet il give her a check over and if happy i leave till friday thanks all

[dave j]

Have you checked the blades are tracking correctly

[dieselcarb]

yes dave they are thanks just gotta set it all up as its got 11deg pitch at mid stick and while im thinking about it that probly dont help but i bodged a v3 head on a v2 heli but any ways ithink its ok

i get a slapped wrist friday if not but that was why i asked as i want it to be perfik but have never seen 1 running up close

[Andy from Sandy]

I wouldn't worry about anything right now as you might make things worse. If you have a tip over now you will be out of action for Friday. I would suggest leaving it for friday buddy.

[dieselcarb]

no worries the T block was buggared so i whacked a new head on and thats got isues ie makes heli shake so hard i yanked it and used a v3 head with an oversize v2 swash lurvely but dont let the missus know u said leave it till friday or i will have to tidy up now