Whats This Guy Done Wrong?

[blade4oo]

i thot all helis were soposed to natually drift to the lift because of the tail rotor
but the guy in the video looked like the tail did the typicall b400 thing and walked on him
and he puld the wrong stick lol i did it win i first started but i skiped the gliding on the froor thing i just jumped it up but i had a year of g3 before i evin bought a heli
and the trim thing ya i yous no trim ether alought of ajusting but i got it
and some advise for noobs "i dont like the word noobs lol " with a B400 is git rid of the stock gyro git a GY401 you should not be fighting the tial win you are lerning to fly your bird it will help you fly that mutch better git your bird flying more like the sims

[LockMD]

Actually this is not the right way to do it bud. You should find an arm that gives you as close as possible to 90 degrees and then fine turn it with sub-trim. The arms move in an arc, if you do not have them all at 90 degrees at center stick, your swash will not move up and down level because all of the arms are not moving in unision.

SPaRX

Okay but.....someone said if you have sub-trim it will be twice in the other direction when inverted :confused:

C'mon now school me. I am getting close to getting some gonads to try, but I need the right set up.

[blade4oo]

ok i going to corrict myself i do yous sub trim to 90 the servo but no trim

[sparx-]

Okay but.....someone said if you have sub-trim it will be twice in the other direction when inverted :confused:

C'mon now school me. I am getting close to getting some gonads to try, but I need the right set up.

No sir... that is TRIM, not SUB-Trim. These are two very different Trims. Sub-trim shifts the entire travel range of the servo. Think of a circle. Say your servo travels from 5 degrees to 185 degress with the center being 95 degress. You apply 5 degress of sub-trim and now your servo travel is 0 degrees to 180 degress with 90 degrees being the center.

With TRIM, using the same starting point, 5 - 185 center @ 95, you apply 5 degress of trim. You travel range is still 5 - 185, but your center is now 90.

Make sense?

SPaRX

[sparx-]

Also, the "it will be twice in the other direction when inverted" part is assuming you have a level swash BEFORE you apply that trim. This is because by adding trim, your swash is not level at center sticks.

Another way to think of it is like this...... Sub-trim is more like if you could "physically" rotate the servo about it's output shaft.

Applying trim is like you constantly applying input on the sticks.

SPaRX

[SeaComms]

Okay but.....someone said if you have sub-trim it will be twice in the other direction when inverted :confused:

C'mon now school me. I am getting close to getting some gonads to try, but I need the right set up.

What they are referring to there is trimming the swash to hover steady (hands off) with a little right trim on what used to be a perfectly level swash, to counteract the thrust sideways from the tail rotor. When inverted, the tail rotor is now pushing in the opposite direction, so the trim you put in to keep it steady hovering upright is now the wrong way and really trying to push the heli over when inverted.

In otherwords, upright you want to push the aileron a touch to the right to counteract the tail push, when inverted you want to move the aileron left.

You can put the trim in by all means if you never plan to fly inverted, but one day you will want to give it a go, and if you learnt to fly with trim to the right, you will need to relearn again with no trim before starting to go 3D.

[jayrat]

Thanks sparx-. Crystal clear!

[sparx-]

Look guys.. this is the best thing to do.

Center your sticks. Install servo arms and get them as close to 90 degress as you can. Then use Sub-Trim to get them at 90. Level your swash at center stick by adjusting the swash-servo links. Move the swash through its range using the throttle stick and make sure that it stays as level as possible. If need, you End Point Adjustments to get it level through the range of motion. Then GO FLY!

I DO NOT use my trims to get a Hands Free hover. This will unlevel the swash and give unpredictable results when you start rolling and looping. It is best to just learn how to compensate for the natural tendencies of how a heli flys rather then trim them out.

YMMV, but this is how I do it

SPaRX