Phasing question

[lpiint]

I have noticed the phasing on my trex 500 is out quite a bit. I can't see any way to adjust it. I read online that the phasing was not adjustable on a trex 250 and am wondering if it is the same for all Align helicopters? If anybody could explain why it is this way I would really appreciate it.

[legine]

are you sure its not your tail kicking out slightly?

[lpiint]

My Trex hasn't flown yet, I am doing final setup.

[Vinger]

Haven't flown, but phasing is out! Are you sure you are not talking about swash interactions while still doing setup. Phasing can only really be determined once you fly, especially on the TRex type of head as it is not adjustable. As long as the head is build properly you should not have any issues.

[lpiint]

yah I might not be describing this correctly. I'm referring to when you line up the swash plate ball with the elevator ball and the blades are not straight across. If that's not a good enough description it is what finless is doing about half way through this vid http://video.helifreak.com/?subpath=...=swashwash.wmv

[Vinger]

On my 500 the swash aligns (pun intended) properly with the blades, so I would check your head built and setup again.

"Elevator link lined up with ball and flybar straight down the center of fuselage" and that's exactly how mine lines up.

Phasing in flight will be experienced as an apparent roll if you only apply elevator or an apparent pitch while applying only a roll input. I have found the TRex 500 to be fairly free of this, BUT it still depends on what make of main blades you use. The Align carbon series of blades and the GCT(Mavrikk) wide chord blades tend to work the best, with the least amount of phasing problems.

[srhadden]

If you have a swashplate leveler for the 500, you can easily get a centered swashplate and easily cancel out the "CCPM" interaction. For example, I set it level at center stick. Then you go full stick, if the swash is not level, you use travel adjust (ATV) to level it. Then do the same for low stick.

[Finless]

I hate to tell you all this but the Trex500 has a built in 2-3 degrees of phasing. If you line up your flybar with the boom PERFECTLY you will see the two front balls on the swash (the inner and the outer) are not perfectly in line. Every 500 I have checked has this built in phasing.

Bob

[Vinger]

Originally Posted by Finless

I hate to tell you all this but the Trex500 has a built in 10-15 degrees of phasing. If you line up your flybar with the boom PERFECTLY you will see the two front balls on the swash (the inner and the outer) are not perfectly in line. Every 500 I have checked has this built in phasing.

Bob

Bob, sorry to disagree with you, I have now checked 3 TRex 500's and ALL have ZERO phase angle built in, meaning that with the flybar straight down the fuselage the elevator/antirotation link lines up perfectly with the ball on the rotating side of the swash.

I have checked and re-checked all of them and they all showed the same zero phase angle, even with carefull measuring it definately have no phase angle built in. Maybe a change happened somewhere in production, but I even put on my old plastic head and that was the same.

[Paco]

Hello there guys.
As soon as I saw this "phasing" thread I got in to see if I could learn more about why my T500 rolls finely to the left but awefully to the right, and I realize it may have something to do with phasing according to the way someone here described it (pitch changes while rolling, or viceversa)...

I've checked the phasing on mine after reading Vinger's explanation, and although I can't assure I'm looking at the right stuff I'd also agree my 500 has NO phasing built in....

I'll stay tunned to fin out more about phasing issues

Thanks.

[Finless]

I guess a picture will be worth a thousand words! I will take pictures of several 500's and show the phasing. This came to my attention when people started talking about the phasing built in on the Atom 500 as it has about 5 degrees. Curious about that I went and checked several Trex500's. Sure enough it has a little phasing as well. Realize it is not much and easily not noticed. DONT use the blades to check. Use the flybar.
Now this was in Dec 2008. Since I just built an ESP recently, I will check it and see if something has changed but I kind of doubt it. I am off to a funfly so wont be able to check and take pictures until next week.

Bob

[Skint Eastwood]

Its known when doing a t500 flybarless conversion to add 2 degrees of phasing in software

[Vinger]

Originally Posted by Finless

I guess a picture will be worth a thousand words! I will take pictures of several 500's and show the phasing. This came to my attention when people started talking about the phasing built in on the Atom 500 as it has about 5 degrees. Curious about that I went and checked several Trex500's. Sure enough it has a little phasing as well. Realize it is not much and easily not noticed. DONT use the blades to check. Use the flybar.
Now this was in Dec 2008. Since I just built an ESP recently, I will check it and see if something has changed but I kind of doubt it. I am off to a funfly so wont be able to check and take pictures until next week.

Bob

Do all these measurements with the flybar only, as I have said in my earlier post. Will try to take post pictures tomorrow as it's pretty dark and rainy to get to helis at the moment.!!!

[Vinger]

Tried to get the best pictures, but the angel is such that it's difficult to get the correct view, but here is my try.

from behind with flybar dead center on fuselage:



From slightly of center, showing balls line up on elevator link:



another dead center from rear:



With head removed and note the washout pins line up with elevator link:




So as far as my experience goes, the TRex 500 has NO or ZERO phasing built in.

[Ah Clem]

It it usually easier to spot it from the top, looking down to see if the washout arms are parallel to the head yoke.

Every TREX 600E I have ever seen has zero degrees of phasing, except mine, which has a very few degrees advance (it seems to roll better/flatter also).

The 500's I have seen have the small amount of advance timing/phasing that Finless Bob describes.

I will look again the next time I am at the field.

[sllimg]

Originally Posted by Skint Eastwood

Its known when doing a t500 flybarless conversion to add 2 degrees of phasing in software

I had a really good setup with the Mikado head conversion on my 500. Phasing wasn't a problem. I recently purchased the new head on Helidirect and now I can't get the phasing right. I have 2 degrees in the software and the heli still pitches forward when doing rolls. What am I doing wrong?

[Vinger]

Originally Posted by sllimg

I had a really good setup with the Mikado head conversion on my 500. Phasing wasn't a problem. I recently purchased the new head on Helidirect and now I can't get the phasing right. I have 2 degrees in the software and the heli still pitches forward when doing rolls. What am I doing wrong?

Type of blades also changes the phasing relationship. I have found that the Align 425D gives zero interactions while the Radix blades seems to give the most. GCT (Maverikk) wide chords are good as well. Cheap carbons from HobbyCity was the worst.

I am still using a flybar, but would surmise that it should be same for flybarless setups. Try other blades as well.

[hawkins221]

Originally Posted by Ah Clem

It it usually easier to spot it from the top, looking down to see if the washout arms are parallel to the head yoke.

Every TREX 600E I have ever seen has zero degrees of phasing, except mine, which has a very few degrees advance (it seems to roll better/flatter also).

The 500's I have seen have the small amount of advance timing/phasing that Finless Bob describes.

I will look again the next time I am at the field.

yes i must agree with you. my 500 don,t have any visable phaseing but always comes out of a really hard elev flip to one side, pain in the ass!!
i also have a logo500 waiting to get airborn with maniac blades and am hoping for some perfection.

[Paulice]

I've just checked my 500 ESP and there is none on my model.
But i can dial it in on the TX if a find i need to, but till now not found the need, and as for forward roll's it will roll better to the right than left but thats the rotor direction and gyroscopic affects.

[lpiint]

Wow this thread is still going. I have found out the problem with mine. I didn't think it was worth mentioning but I have a Trex 500 clone (EXI 500). The head is so poorly made that the washout arms were bent along with numerous other pieces. Thanks again for the help guys.