Boy am I lucky!

[sgtmike74]

Check this out. I discovered it after trying to solve the mysterious “clanking noise” that was coming from my Raptor 30, accompanied by a momentary stop of my tail blade. I am so glad this didn’t give way while I was in flight!

[tdswan]

That's not good! Wonder how that happened?
It's always nice to catch these problems before they cuase a real problem. :)

Congratulations on actually getting a book on Access. Maybe at least one of us in here will understand it now! :p

[heli-cuzz]

Good catch sgt.

Ever lose a tail while in flite?

I have with my cp blade... LoL. It spins and spins and spins... Then crash :eek:

[TORO]

Lost tail=immediate throttle hold !!!! MUST DRILL INTO HEAD MUST HIT HOLD HOLD HOLD... I ve lost the tail on my rappy twice... both times succesful auto via throttle hold...

[sgtmike74]

I never 'lost' a tail on my cp but I have heard of people putting a small amount of CA between the tail blades and the gear.

[kcgraves]

I lost the tail on my MX400Pro last week with a brand new set of main carbon blades on it. The servo link rod for the tail came out of the rod end. Was about 30 feet up. Spin, Spin, Spin, flip, CRASH. Main blades, feather shaft, main shaft, tail shaft, fly bar. New blades should be here tomorrow. Next time I'll try the throttle hold, if I remember.

CP sometimes just goes. Get one good motor that lasts for months then one or two that last a week.

[sgtmike74]

When I originally posted this I was sure that the source of my clanking noise was coming from the damaged pulley. After replacing the part imagine my surprise when I still heard the clanking noise emanating from my tail section accompanied by the momentary stop of my tail blades. Don't get me wrong, I am glad I found this part before it failed completely I just felt lost as to what to do next concerning the noise. I started looking at different forums, namely raptortechnique.com and the raptor own manual, when I made a discovery. If you look at the pic of my original post (#1) you might see it. My blade grips where on backwards!! According to raptortechnique.com the lead edge of the top blade should be facing backwards AS WELL as the pitch arm of that corresponding blade grip. In the manual I had to zoom in very closely to make it out but sure enough it was true. So I had to flip my grips as well as switch out the grips to make sure they were facing the right way. They are now set up like the following picture. Once I did this tho, I had to manually flip the reverse switch on my GY401 to keep the heading hold holding in the correct direction. (failure to do this will lead to a really bad day). After all said and done I tested my heli out and the noise was gone!! Not only that, but the heli holds much better in the None Heading Hold mode as well. So if you are experiencing clanking noise looked to see what your blade grip orientation is.

[vapochilled]

good find! at least you have a conclusion, and found the damaged pulley.

[sgtmike74]

I might have spoke too soon on this one. Though my tail blades are now set up in accordance with the manual as well as raptortechnique.com that noise started up again after my third flight. I tighten up my boom with the help of a buddy and the noise disappeared, but came back later that day.

This is what I THINK is happening inside the boom.

The belt itself forms a loop that goes from the main gear assembly through the boom around the tail pulley and back again.

Half of the belt is pulled, while the other half is pushed.

When the engine spools up it increases the load on the belt and spins it faster which causes it to stabilize and not bind. (no noise)

As soon as the load is gone (you drop your throttle) you still have excessive rpm of the belt.

Im thinking that the half of the belt being pushed is bending and warping
with this high rpms/no load, instead of staying tight. Just like a tank tread when turning. When the belt warps the teeth on the belts are catching each other and snagging. Every time the belt snags on it's self it causes the tail blades to stop here and there.

My next step to tighten up the boom. place a mark on the boom exactly where it enters the main frame. If the boom slides inwards over a period of flights then my mark will disappear and let me know my problem lies with the securing of the tail boom.

[cbflys]

If you suspect or ultimately find out that you tail boom is sliding - you may want to try to wrap one layer of double sided transparent tape around the end of the boom. This will help by increasing the diameter slightly as well as provide some extra friction from the adhesive.

[sgtmike74]

That's a good idea, I think I will mark the boom first just see if it did in fact move, and if it did I will apply some tape to thicken the boom.

[tdswan]

How cold is it there? In the cold, that Raptor boom will actually shrink up. Mine shrinks so bad that even when it's too tight indoors it will be too lose outside. I usually ground my Raptor in the winter months.

[cbflys]

td - you're right. I forgot about that.

I don't enjoy freezing my "you know what" off anymore - so I haven't done any winter flying in years.

[tdswan]

The sad thing is that it was right there and neither of us ever noticed it! :p I had the same experience last winter and since haven't flown in the winter months with it. Usually from about 45 degrees and up it's not a factor and that's about my cutoff point for flying.

What happens is the belt gets so loose that the teeth hit each other and bounce against the boom, hence the tinging sound.

[sgtmike74]

I am up in Washington state right now and it can get cold. On a side note maybe I can talk the wife in letting me get a carbon boom. I would love to get a Titan 50 carbon boom and start converting this thing over, not sure of the cost though :D

This sort of brings up another question. If you bought a gallon of fuel in the winter months. You stored it in your garage without breaking the seal, will the fuel go bad before the summer months hit?

[tdswan]

Not if it stays sealed. Just keep it in the house and it should be fine. Two guys that live near me buy a pallet of fuel together each spring and what they don't use gets stored until the next season.