J Perkins, Twister Mini scale, wont lift off?

[PurcyP]

Its not spinning in circles before anyone asks.

 

Ive erm..well my amazing flying skills...meant ive broken well i guess all of the blades, it has little ball ends for swash links to go on etc and they keep breaking off if you crash.

 

thing is..ive been replacing em etc and now the helicopter has no lift?

 

Are these blades specific? as in one set on the lower and one set higher because i cant see any differences in em.

 

I r confused..its a coxial by the way

[Nitroholic]

Make sure you have the blades on the right way up... Co axial helis spin the 2 sets of blades opposite ways, so it may have directional blades

[PurcyP]

Yeah tried all that, 

[Nitroholic]

OK....well if hte blades are correct, the right way up and spinning the right way....it should lift off. Your co-ax has fixed pitch blades, so the faster they spin, the more lift you get. As long as it is spinning up to the right speed...it should lift off

[PurcyP]

i think ill have to make a short video

[PurcyP]

okay so i got some replacement blades

 

it now takes off

 

but its spinning...tried the trims but not seemingly doing anything :\

[Nitroholic]

co axials control the rotation left and right through the rotor speeds. Increase or decrease the speed of one set, relative to the other, and you will induce a rotation of the heli.

 

If it is spinning round and round and won't stop, you may have a faulty motor.

[mugen mark]

a slightly bent shaft can cause it to

[Tamiyacowboy]

what way does it spin 

say your standing behind the heli what direction is the spin left - right.

 

once you know direction of spin, look down from above heli.

notice the top blades will point one direction and bottom blades point another.

ie: one set clockwise other anti clockwise.

 

top set spins clock wise and bottom set spins anti clockwise. we know the heli spins anti clockwise.

so this deduces our problem lays with the clockwise rotation. we say clockwise because this blade should equal thrust as the other set,

but we have a loss of thrust from the clockwise set and this induces an anti clockwise rotation.

 

now you have worked out what rotation is causing problems you can start to cancel out areas.

blades are new you say so we deduct blades from the problem. you fitted them correct ie: one set left other right ( like a quadcopters blades)

now we have two areas of interest , Motor-pinion - drive gear main shaft. a motor thats on its way out will not work as well it could have started to loose its brushes

or just fall apart from use and abuse. if all else fails you look at the motors and the main board drivers ( aka fets)

Edited October 14, 2013 by Tamiyacowboy

[PurcyP]

had my boss look at it, faulty motor it would seem so will be sent back to J perkins n see what happens

 

thanks folks