BladeCX2Two

Hey guys-

I'm having a new problem with my Belt CP. I can't seem to get my tail from going counter-clockwise without giving it a good amount of tail to the right input. I've already maxed out the the throw on the tail blades and actually wrecked one servo by trying to go to far and in turn stripping out the gears inside the servo. The tail blades are spinning in the proper direction. There aren't any nics or breaks in the tail blades either.

One thing I can tell you is that I just put on a set of brand new balanced Align 325 carbon blades on Thursday. I know the stockers are 315mm so I'm adding on an extra 20mm of rotor span. Do any of you think that my problem is the tail blades themselves in not being long enough to compensate for the longer main blades?

I just got done rebuilding most of the head assy tonight due to a mishap on Friday. Somehow my ESC went into brake mode and when my blades hit the gound, it sheared off the plastic upper head. I just got done running it outside and other than having to hold the tail stick pretty far to the right, it flies pretty darn good. I don't know when else to try.

Thanks.

Cheam24

Maybe, as you said, the tail blade is not big enough for the main blade. I don''t have a Blade CP.
But in my case for a HBK2, I used two larger tail blades which helps. I made them myself, way bigger than stock. About 20 percent larger. See my post in tuner shop.

gnd2

What's your head speed? You may just need to increase it. The 325's will produce more drag so you'll have to compensate, but I don't think they should be too much of a problem on a Belt CP.

evdreamer

I have 320mm blades on my Belt CP and have no problem. Do you have zero pitch on the tail blades with no rudder input? If not try moving tail servo, most likely backwards toward the tail. Are you in HH mode or standard rate mode when this happens? How high is your gain on the gyro?

BladeCX2Two

Yes, I do believe it is at zero pitch in its idle state. I have the stock gyro. I tried both norm & rev tonight. In one mode she goes into massive tailspins so I switched it back. I tried various gains on the gyro also. I don't think it's a gyro problem after trying all that.

1) Tail rotor is spinning in the proper direction.
2) I tried various belt tensions
3) Tail blades are on the correct way.
4) I even tried a brand new tail shaft tonight.
5) If I move the servo forward anymore and give it more pitch it will pretty much fix the problem BUT, If I give it rull right tail input, it will strip out the servo because it's then forced to pull the linkage more than it can. I already put a new esky servo on it yesterday. Hate to ruin this one also.
6) The linkage is not binding on anything.
7) I set the trim all the way to the right, then I gave it full right input on the stick and then move the servo as far ahead as it would go to the point just before she would start to skip teeth inside the servo.

Guys- I can't think of anything else. This isn't even at full head speed either. She starts to rotate clockwise even before liftoff. I'm forced to give it input almost from the get go.

Any further ideas?
Thank you.

gnd2

The problem is you're not getting enough thrust from the tail to counter the torque of the main rotor. When you put the longer blades on it increased the torque that the tail needs to overcome. You compensate for this by sliding the servo like you mentioned for more pitch, but if you're so close to the limit that you're stripping the servo then it means you either need more speed or a bigger tail rotor to get more thrust from the tail.

The simplest thing to try at this point is to increase your head speed. I think the stock radio has some knobs for adjusting the pitch and throttle curves right? You need to adjust those to get more head speed at hover and it should help (increase the throttle knob and/or decrease the pitch knob).

I don't know what you would replace the tail blades with to get more thrust.

The tail on the HBK2 is said to be a little underpowered and there's a tail drive pulley upgrade available that increases the speed of the tail relative to the main rotor, but I've never heard of this being a problem with the belt cp before.

Druss

I'm with gnd2, I think you need more thrust, either with tail blades that have more surface area or increased speed. Try and see if tail blades from other 450 size helis are larger.

BladeCX2Two

Hey guys- I really appreciate your responding to this. I took it out again after work. I did what you said by increasing the head speed by dialing down the left knob (hov.pit).. head spead increased but also took more rpm to lift off. This helped the nose a tiny bit. It was the knob on the right (pit trim) that made a bigger difference. I dialed this knob all the way down. Doing both of these helped but still isn't enough. In saying that at least it proves the theory of needing more tail thrust like you guys said. With the 325's on there, it's just too much for the tail to compensate. Also keep in mind, these are 325 fiber blades not wood, which I think are heavier than wood. Maybe that's why you other guys aren't having problem with your 325's...maybe you have wood ones. I love these blades and plan to stick with Align. I just had too much problems with the coverite material coming off the stock blades. Plus these seem way more stable.

Just a few moments ago, I ordered 2 sets of Align 315mm fiber blades, plus 3 sets of Align 450 carbon tail blades. They all should be here by early next week.

Thanks again for your advice.

blk822

Are you using a pitch gauge to set up your blades? You my have to much pitch at to low a head speed.

BladeCX2Two

Thanks for the reply... I haven't checked the pitch at all lately since I put on the Align blades but it very well could be off several degress. I'll post back later on today. Gotta go to work.


Thanks again.

aland25

Just a quick suggestion, you might try a different tail servo.
Even though it looks like it is working properly, it might not be holding well when you get your head spead up.

Sorry for the post if you have already checked this.

BladeCX2Two

aland25- yes i did put another brand new servo on it and it does the same exact thing. But thanks for your reply though. I checked the pitch on it tonight and in normal flight mode, at 50% throttle she has about 5* of pitch. At full throttle in 3D mode, she has about 9 1/2*... at mid stick in 3D mode, she is spot on 0*. I'm pretty happy with those numbers.

My Align 315 blades and trex tail blades shipped. I might have them as early as Saturday.

I flew it tonight a whole batteries worth. Other than having to give it constant tail input, It flies very nice. I don't know if it's more stable because of the 325 blades or just the Align blades period. To give you an idea of how much tail input I have to give it, I have to hold it about 1/3 of the way between neutral position and full right. Not bad but until it's fixed, I don't feel comfortable in doing anything except for hovering around. I'll first try the trex tail blades with the current 325's I have on it. If that don't cure it, then I'll put the Align 315's on.

Thanks again.

BladeCX2Two

Well guys-- My Align 315 fiber blades and tail blades showed up today. I immiedately tried out the tail blades. Had to thin them out a bit as the stock esky ones are thinner. Took it outside and SAME THING, nose to the left. The Align 450 tail blades are probably only 3/16" longer than Esky... So then I put on the 315mm blades and kept the trex tail blades on. SAME THING, nose to the left. Servo was as far forward as I could go without hearing that it was skipping teeth.

Needless to say, I just figured out what the problem was. I had the linkage for the tail hooked up on the outside of the white servo bell horn. It supposed to be on the inside of it, so the linkage is acutally between the tail boom and the bell horn. On my heli, you could actually see that linkage curve downwards. This was creating a great deal of bindage. I just found this while I was paging thru the book looking at pictures. Now I sit with lots of extra tail blades and 3 sets of Align blades. That's the good that came out of it.

Flies like a top now. Actually had to move the servo back just a hair.