What have I done wrong?

[powelly999]

https://youtu.be/PEwiX0TtW_A

Hi all
Above is a video of the problem (I hope!). I adjusted the throttle curve to almost a flat line to raise the head speed and took off some negative pitch at the the bottom too but still the same issue as can be seen. I did notice on one run up, some tail wag before it started to spin so I tried some gyro gain settings, 25%, 50%, and 75%. None made any difference to the problem, in fact the 25% setting just seemed to let it spin quicker, causing the training skid to unclip itself. Anyone know how much TREX 470LM tail rotor blades are? :-(

Beginning to think I might just put it back on the shelf
Andrew.

[The Tok'ra]

link to tail blades here, if you do need them. Did they get damaged when the heli was spinning? https://www.align-trex.co.uk/69-tail...-hq0693at.html

O.K. So it spins the in the same direction as the head, so it's overcompensating for some reason. Can you do a video of what I asked you to do in post #13 please, and show the Tx stick movements too please. Edit:- I think you checked this already, but can you also check if the tail is spinning the the right direction too, it's hard to see in the video. When the head is spinning clockwise, the tail blades should be spinning ant-clockwise looking at it from the side the tail blades are on.

[trillian]

It kinda looks like the tail blades are on backwards 'may just be an optical illusion.

[The Tok'ra]

yeah, you might be right, it's hard to tell, but it still wouldn't cause the tail to overcompensate like that. I've seen posts on HF where people have flown around with the tail blades the wrong way and it still flew, but i bet the tail hold was a bit off LOL

[powelly999]

Thanks again all
I’ve checked the tail rotor blades and they are correct.
Here’s a video of what happens on the table
https://youtu.be/FzXnByhh1dQ

Thanks
Andrew

[trillian]

Nope... the tail blades are on backwards amigo.

I’ve checked the tail rotor blades and they are correct.

[powelly999]

Don’t think they are on the wrong way? Looking at the side at the tail the leading edge is rotating clockwise while the main rotor rotates clockwise looking from above. The original video may look like it but I’m pretty sure this is correct
Thanks
Andrew

[Magic919]

Compare it to the pics on here https://www.align-trex.co.uk/align-t...rh47e01xt.html

They look backwards to me too. It does look a lot like it uses the wrong direction to correct the tail. It does a great pirouette.

Don’t give up. I’ve built a tail wrong, set up mixing with FBL and even had the running gear spinning in reverse. Eventually I sorted them all and I’m just a newb.

[The Tok'ra]

Yup, tail blades are the wrong way round for the correct direction of rotation. It should be spinning Anti-clockwise. If your tail rotor is spinning in the same direction as you have the tail blades, then that's your problem, the belt is making your tail go the wrong way too!! Any that will make the tail do very strange things indeed!! Also, Why did you raise the throttle stick up before you moved the tail on the bench? it shouldn't matter where the throttle stick is, the tail should behave the same regardless, and it looks like it is correcting the right way to me.

[powelly999]

Yup, tail blades are the wrong way round for the correct direction of rotation. It should be spinning Anti-clockwise. If your tail rotor is spinning in the same direction as you have the tail blades, then that's your problem, the belt is making your tail go the wrong way too!! Any that will make the tail do very strange things indeed!! Also, Why did you raise the throttle stick up before you moved the tail on the bench? it shouldn't matter where the throttle stick is, the tail should behave the same regardless, and it looks like it is correcting the right way to me.

Ahhhhh the penny drops, although I have the blades on to suit the rotation, the rotation is wrong. I expect the belt twist is wrong sending the tail rotating the wrong way. I’ll take it apart later to check.

Thanks Tok’ra and the rest of you that noticed. I’ll report back to let you know.

Cheers all

[trillian]

We've all done it! When I first built my Hirobo Sceadu 50 I somehow had a double twist in the belt Surprisingly, it still flew, but there was so much drag it was crazy.

Ahhhhh the penny drops, although I have the blades on to suit the rotation, the rotation is wrong. I expect the belt twist is wrong sending the tail rotating the wrong way. I’ll take it apart later to check.

Thanks Tok’ra and the rest of you that noticed. I’ll report back to let you know.

Cheers all

[The Tok'ra]

Ahhhhh the penny drops, although I have the blades on to suit the rotation, the rotation is wrong. I expect the belt twist is wrong sending the tail rotating the wrong way. I’ll take it apart later to check.

Thanks Tok’ra and the rest of you that noticed. I’ll report back to let you know.

Cheers all

Yeah, must be the belt making the tail go the wrong way. It explains exactly why it's doing what it's doing. put a small torch between the belt at the front of the heli and look down the boom and you should be able to see well enough if the belt is twisted or just hooked up the wrong way round.

[The Tok'ra]

We've all done it! When I first built my Hirobo Sceadu 50 I somehow had a double twist in the belt Surprisingly, it still flew, but there was so much drag it was crazy.

Yup, we have all done something stupid at some point. It my early days, before I stopped using Normal mode, I went inverted forgetting that I had not flicked up into idle up, I did that a few times before I stopped using normal mode at all, and thankfully it was almost always with a sub micro heli, so no damage to the heli, but I did do it with my Oxy 3 once, and that bent the FS, and that was the last of Normal mode. LOL!!

[trillian]

I did that just a few weeks ago! With my Trex 500. My first thought was just that the governor didn't latch on properly as it's not the best gov to say the least. Then realised I had not flipped to idle-up. I got away with it though

Yup, we have all done something stupid at some point. It my early days, before I stopped using Normal mode, I went inverted forgetting that I had not flicked up into idle up

[The Tok'ra]

I did that just a few weeks ago! With my Trex 500. My first thought was just that the governor didn't latch on properly as it's not the best gov to say the least. Then realised I had not flipped to idle-up. I got away with it though

Yeah, It's just too easy to forget. That's why i just did away with normal mode completly, there really is no need for it these days, apart from when setting up the ESC anyway.