: trex500 swash plate turning on full collective up?



nzchopper
19-07-2012, 08:19 AM
Hey guys, I got power to the servos etc on my trex 500 for the first time last night. its my first CP chopper.

Am trying to get everything straight and correct.

Basically, when I go collective/throttle up, at its full extension - the swashplate spins slightly - usually counter clockwise.

It appears to stay basically level throughout the the travel range but the fact that it spins slightly just dosent look right to me.
i.e so the balls on the swash plate are no longer straight up and down with the balls on the servo horn.

is it normal? am i chasing an impossible dream trying to get it not to spin?

thanks guys.

bobes919
19-07-2012, 08:57 AM
Did you use a swash plate leveler ?

Seems like the servo links may be longer than the others when in full throttle ? Causing the swash to turn . Using your eye as a guide is not good enough in my opinion .

I use 50% pitch curve when i set my swash plate using a leveler and across the whole throttle range from 0-50-100% thorrtle i make sure its perfect , then switch back when your ready to fly to a linear pitch curve .

Mr.Leopard
19-07-2012, 09:09 AM
Have you centered your servos with your radio at mid stick? Arms should be perfect 90 degrees and swashplate should have 0 pitch and perfectly level

nzchopper
19-07-2012, 09:12 AM
Nope I havent used a leveler as yet. I had one arrive yesterday so will give that a try.

Initially looking at it it looks as if the tool may be too tall, ill find out though. (its one of those turnigy ones, if anyone is familiar with it)

I could get my engineer friend to mill the top off it if it is too tall..

I also thought i may have too much movement in the servos as it only spins at its maximum up position.

so, to confirm - the swashplate should not turn?

bobes919
19-07-2012, 09:23 AM
Nope I havent used a leveler as yet. I had one arrive yesterday so will give that a try.

Initially looking at it it looks as if the tool may be too tall, ill find out though. (its one of those turnigy ones, if anyone is familiar with it)

I could get my engineer friend to mill the top off it if it is too tall..

I also thought i may have too much movement in the servos as it only spins at its maximum up position.

so, to confirm - the swashplate should not turn?


I dont believe it should turn , like Mr baja said you need your servos at 90 degrees which is mid stick .

Peter
19-07-2012, 09:26 AM
By "turn", do you mean rotate , or lean slightly back/forward or left /right ?

Most will rotate slightly, that's the play in the anti rotation arm; but a flybarred heli shouldn't have the swash leaning in any direction over it's full travel.....

nzchopper
19-07-2012, 10:33 AM
By "turn", do you mean rotate , or lean slightly back/forward or left /right ?

Most will rotate slightly, that's the play in the anti rotation arm; but a flybarred heli shouldn't have the swash leaning in any direction over it's full travel.....

yes i mean it rotates slightly,

and I have been trying to center it with my throttle at its lowest position..:frusty:
should i set throttle to 0 at center stick?

edit, ignore that bit, i think i should set a flat throttle curve and just disconnect the motor or set hold to 0% while messing with the swash?

aalin13
19-07-2012, 11:27 AM
edit, ignore that bit, i think i should set a flat throttle curve and just disconnect the motor or set hold to 0% while messing with the swash?

You can either disconnect the motor or use throttle hold on the TX. The main thing is which ever mode (normal/stunt/TH) you use to set the swash, you should use a linear pitch curve with 50% at mid stick, and have your throttle stick centred on the TX.

Hope that helps!

Mr.Leopard
19-07-2012, 12:06 PM
Ok...do this step by step

Disconnect motor

Uninstall servo horns

Turn everything on

Install servo horns are 90 degrees at throttle mid stick or 50%

Adjust sub trims so every servo is perfectly 90deg

Install adjust push rods untill your swash is perfectly level and your blades have 0 deg of pitch

Understand?

nzchopper
19-07-2012, 12:13 PM
Ok...do this step by step

Disconnect motor

Uninstall servo horns

Turn everything on

Install servo horns are 90 degrees at throttle mid stick or 50%

Adjust sub trims so every servo is perfectly 90deg

Install adjust push rods untill your swash is perfectly level and your blades have 0 deg of pitch

Understand?

Thank you sir, I understand. :)
Now im just hanging out till I can leave work and get to work on the chopper!
Ill let you guys know how I get on, and will no doubt have more questions!
Thanks again

nzchopper
20-07-2012, 05:50 AM
Ugh, once again I fail to see the obvious!
That plastic bit at the rear of the rotor head with the slot in it to guide the rear swash ball link with the long stem on it...
I had that bit of plastic the wrong way round, so it didnt guide anything...i thought it was a strage carry handle or something LOL

EDIT: I had this bit backwards...lol (not my heli)

http://t1.gstatic.com/images?q=tbn:ANd9GcSQS2Ueth02xiHXFMgjJND8mnVRnuchvma5pQEZ2fBg-gj8Dsd6sw

stevo1957
20-07-2012, 06:47 AM
That's called the anti-rotation guide mate.

Don't feel bad.........we've all done silly things with our helis but that's just part of the learning process.

Cheers,

Steve

nzchopper
20-07-2012, 08:32 PM
I got the swash plate sorted - and my mate machined down my swash plate leveling tool and cut a slot in it so I can slide it on and off without taking the head off, so thats nice..

BUT the dramas continue!
I got the blades on and spun it up just a little to see if any issues immediatly presented themselves and they most defifnitly did. As the rpms increased I got a HUGE wobble, didnt take me long to find that my main gears are (were) completly warped.

I have just spent the last couple of hours at my mates machine shop turning them down to true..
What a screw around that was! We had to machine a rod down to size in the lathe to hold the main gear, cut a hole in the dead center of it on the mill so we could secure the gears to the rod with the jesus bolt in the lathe and machine them down to true..they were WAY off.

I have just got home from the workshop and am about to refit the gears...hopefully they will be good now.
It was very much a fix them or brake them trying mission as they were COMPLETLY USELESS as was...lets see if this is better..the mitutoyo gauges say YES!

nzchopper
20-07-2012, 09:25 PM
Installed the gears and gave it some power - the main gears are now good and spin true, no more wobble in the system.
I kept the mandrel tool incase I get any more warped gears in the future so we can turn em down to perfect quickly with no messing around...
I dont want to get ahead of myself..but I may have lift off tomorrow =O

Will keep the forum informed =) no doubt ill be here tomorrow saying i stacked it LOL!