Out of track Raptor Blades

[jschief]

Can Blades be out of track as much as 4 degrees of pitch. This seems to be a little excesive. I have maverikk wood blades and I have checked all linkages and they are all the same lengths.

Can a bent flybar cause this problem. The flybar was bent alittle and I straightened it. I have a replacement coming but the flybar looks straight I just wonder if it could have twisted a little to cause this.

[ClayK]

Feathering shaft? If it's been in a crash, I'd check that too.

Check the bearings.
Check control arms, make sure they aren't loose.
Make sure flybar is equadistant from paddle to paddle.
Check set screws.
Check the flybar seesaw, mounting screws might be loose (don't ask me how I know this.)

[jschief]

Feathering shaft, is that the shaft that connects both blade grips together and goes thru the rotor hub and blade dampers? I have changed the main shaft and this shaft that connects both blade grips because both had a very slight wobble when rolled across a flat surface.

All screws and and control arms have been checked and are not loose.

[ClayK]

Yes, it's the shaft that goes through the rotor hub that holds on the blade grips.

You pitched out both blades using a gauge? Screws and arms all tight and it's still off on one side?

hmm.... Do the blades grips move/jiggle or are they tight on the hub? Are you only seeing it out of track in flight? Are you using woodies or carbon fiber?

[jschief]

Woodies, I have a set of carbons coming with a new flybar. I do not trust the my rebent flybar.

I had a perfect landing in a tree, this is the reason for the replacement of the blades. Everything else seems to be good.

[ClayK]

Flybar could be causing it out of track, but that may not be the end all and be all of the problem.

Wood blades can get wet (nitro exhaust and water, don't ask me how I know this) and balance can be thrown off, suggest checking the CG on them and the balance.

If replacing the flybar (make sure the distance is equal from paddle to paddle from seesaw) and/or blades fixes it, you know what the problem is.

[flyinfool]

Are you saying that with a difference of 4 deg of pitch the blades are in track?

If so there is something still bent or damaged from the crash.
In addition to all of the above suggestions, check the head to see if the head-block itself is bent or the hole that goes onto the main shaft is stretched out causing a loose fit.
It could also be a damaged damper.

I would think that with that much of a problem that there must be a lot of vibration.

[johndale]

Can Blades be out of track as much as 4 degrees of pitch. This seems to be a little excesive. I have maverikk wood blades and I have checked all linkages and they are all the same lengths.

Can a bent flybar cause this problem. The flybar was bent alittle and I straightened it. I have a replacement coming but the flybar looks straight I just wonder if it could have twisted a little to cause this.
I had a lot of problems with the maverikk blades of all types on my Raptors 50m V2. Just my 2 cents.

[jschief]

I only flew for a little while and tried to get the blades to track. I got the 4 deg difference with the pitch guage. I haven't had time to put the blades on a table to make sure the blades are true.

The dampers seem to be ok, the flybar was bent and I straightened but maybe it got twisted a little, I think this might be the problem. I won't know until I can look at it more closely on thur. I have a flybar and carbon blades coming I will check with the new stuff when it arrives. :dontknow

[HelicopterJohn]

Hi jschief,

You said:

Can Blades be out of track as much as 4 degrees of pitch. This seems to be a little excesive. I have maverikk wood blades and I have checked all linkages and they are all the same lengths.

You issue is probably with the blades especially if you are turning them at a higher RPM. Also, woodies can fly great one day and then suddenly develop issues. Furthermore, it is important that the area under the blade attachment area on the wooden blades is coated with CA to strengthen them. Woodies are fine for hovering and basic flying around but sometimes tend to have tracking issues as you advance your flying skills. Incorrectly aligned flybar paddles can also effect blade tracking.

Also, you should check to see that the thrust bearings in the blade grips are properly installed. The small internal diameter always goes towards the blade. The large internal diameter always goes next to the thrust collar.

Blade grips over time can become sloppy and sometimes effect the tracking of the blades especially if one is worn more than the other.

If you get a chance you can check out my Website (see link at the bottom of this post). It will give you some information that may be helpful in the setup of your Raptor 50. If you click on the Raptor 50 link it will show you the method I use and the associated tools I use in the setup of Raptor 30/50 V1/V2 machines. To achieve a nice flying machine this setup helps. Also on my website is a Raptor linkage setup form that is nice because it allows you to record the length of all the linkages and in case you crash or replace any ball links you can verify the correct during rebuild. The form is pretty painless to use and is free download.

In my opinion a level swashplate properly centered in the collective range with the flybar paddles leveled and the linkages of appropriate length (linkage pairs should be identical length) is essential to a correctly setup helicopter.

Hope this helps in some small way.

:D

[jschief]

Thanks for all the help. I have logged a full gallon and about 2 hrs of flight time before I did not account for the tree getting in my way and I am sure I have installed all bearings and correctly. I just was wondering if this could be normal. I did not have this problem before the crash. I have replaced the main shaft, the spindle shaft because these were slightly bent. All the other parts seem to be fine including the bearing these parts ride in. I have a flybar coming ups I will let you know if this fixes the problem.

I have glued the woodies blade grips I will try re-balancing. I also have a set of carbons coming.

Everything seem to be fine until the crash. Tomorrow I will have time to look at it I will not fly it until the other parts come.

[jschief]

One more question concerning the fly-bar. There is two notches in the fly-bar, is it ok if these notches are slightly out of alignment with each other. I thought these 2 notches should be flat in the same spot on the fly-bar.

[Seeker]

Those notches are where the arms tighten down on the flybar. Just be sure the set screws are in the notches.

[HelicopterJohn]

Hi jschief,

The set screws that hold the control arm to the flybar need to be in the center of the notches when tightened. You should measure from the outside of the control arm on each side and make sure the distance to the end of the flybar on each side is equal. You may have to play with this a little to get proper alignment.

Also when you screw the paddles on measure them to make sure they are the same distance from outer edge of the control arm to the most inner part of the flybar paddle on both sides.

Make sure when the swashplate is level that the flybar paddles are level. They sell flybar paddle alignment gauges for this purpose.

Just some things that may help.

:)

[jschief]

I just fiqured the flats in the notches should be flat in the same part of the flybar.

I have replaced the flybar with a new one this morning and both blades are alighned at the same pitch and about 12 deg pos and -2 neg. I will do some more fine tuning because 12 deg pos seems a little high in the beginner setup.

I can hover pretty well until the mishap (see above) so I think I might change to intermediate setup. I have taken the training gear off and I have about a 2 gallons in.

Thanks again for the help, I learned it is cheaper to replace the flybar than trying to straighten it. :wink:

Now to log in some more flight time. We have had some sleet and some rain here hopefully this weekend will be better.

[Seeker]

I would keep the 12 degrees if your engine can handle the pullout at that pitch... I say that because I have mine at 13 with no problem. It helps when I get in trouble and need to pull out hard with some positive pitch.

That being said, I'm getting ready to tone down my positive and add some more negative.