450 450 Heli loss of aileron and Aux channel

[DoninIA]

Hello,
Been lurking here for a while.
Haven't posted much, but I learn more by listening than by talking.

Just got my HK450 Pro put together and have about 10 batteries run through it practicing hovering.
I've started to develop a problem and it seemed to be getting worse tonight.
Spun the main rotor up and just lifted off the ground when I seem to lose left and right cyclic temporarily and then it would come back.
Elevator and tail servos still worked just fine.
Also throttle seemed to work just fine.
I was able to set the heli down.
Everything appeared to work ok on the ground.
Another attempt, heli started to tip right and would not respond to left cyclic.
I had the blade tips disintegrate when they struck the ground. Use wood blades when learning, excellent advice
Only damage was the blades.
Replaced blades, spun it up again, I left the throttle at mid point and attempted to give a left and right cyclic, servos would not move.
The moment I shut the throttle down, everything worked fine again.
Tomorrow I will tear into it and check the RX and connections.

I am using 3 Corona DS-919MG servos for the swash plate.
Orange 7 channel DSM2 for the RX.
Turnigy 9x for the TX.
HK plush 40A ESC.
Turnigy Typhoon 2215 motor
ASSAN GA410 Gyro.
Power HD 3688HD Servo for the tail rotor.

I started spinning this up 3 days ago, Yesterday I was finally confident enough to hover.
All seemed to be going quite well until today.
This morning I could have swore that I lost left/right cyclic for a moment, but wrote it off to being nervous.
Tonight this problem really started to show up.
I have had a few landings that were a little hard, training gear came in handy.
Also fwiw, I have been practicing on a V911 fixed pitch for the last couple months.

Doing a little searching, I see a few people have had problems with bad solder joints in RX's.
I'll put mine on the bench tomorrow and see what I can see with the O'scope.

Anyway, just checking if anybody has had a similar problem or if someone has any advice on what to look for.

Thanks !
Don

 

[Tony]

I don't think it will be a solder joint as the issue is resolved when you let off the motor. To me this is screaming BEC ISSUES. It sounds to be that as you are forcing power through the motor, the BEC just can't keep up, thus you lose power to the servos. I didn't read anything about What size battery you were using though, but it needs to be capable of providing at least 45 amps without getting too hot. If you have another ESC, then hook it up and see if the issues go away. I posted a buddy code in the for sale section to a YEP 45a ESC from the USA warehouse that will save you a bit of money (if you act before it expires) if you decide to get a better ESC. I myself have not had any luck with HK, Plush or any of the other ESC's and I'm taking a leap on teh YEP, but Lee, Gaba, Jesse and many others on here are running them with great success.

 

[wolfman76]

I run exceed rc proton 30 amp esc's on both my 400 blade and exi 450 with not one problem also use same esc on my spider quad

 

[Tony]

I used to run a 30a ESC on my 450, but the slow start is a joke, and it got pretty hot with the alpha 400 motor. Just a bit too small IMO.

 

[Lee]

I would check all the connections as you were thinking to do. Wiggle the wires while moving the cyclic stick to see if anything cuts out.
It could be that when spooling up, the vibration is causing something to come loose but reconnect when spooled down.

 

[DoninIA]

Thanks for the replies.

Tony, I'm using Turnigy 2200 mah 25-35c 3s batteries.
Also I have noticed my batteries are pretty warm when I remove them from the heli.
Motor seems warm, but not near as warm as the batteries.
Also funny you mention the BEC, I have an Extra 260 that is waiting for me to replace the landing gear.
I am having a similiar issue when I get airborne, the plane wants to roll right and it is all I can do to keep the wings level.
I have suspected the BEC in that case.

Lee, I have taped the servo plugs into the receiver, but that is going to be one of the first things I check also.
I'm using channels 1 & 6 for the aileron channels, so both of those would have to have a loss of connection while everything else is working.
I think I have seen some people actually glue the connections in. I'm sure my tape job is not doing a very good job of holding everything in place.

I used to fly nitro airplanes about 11 years ago.
Flew for about 3 years.
Electric was just starting to get popular.
So, all this electric stuff is very new to me.
Also, I was just starting to venture into heli's when I left the hobby.
There just wasn't much help out there, at the time, and several crashes later I gave up RC all together.

Also Tony, thanks for your video that explains how to match a motor to esc to battery.
I came across your video and was finally glad to have someone put it into terms that were understandable
and not trying to dazzle me with a lot of technical info.

I'll report back what I find.
I wonder if I could put a watt meter on the BEC and measure the current going into the receiver when I am at mid throttle and giving cyclic commands?
Might be another test.

Thanks,
Don


- - - Updated - - -

Yep ESC's ordered.
Now the wait begins.



Don

 

[DoninIA]

Looking at all the specs.
The Turnigy plush 40A has a max current of 3 amps on the BEC.
The YEP has a max current of 6 amps.
Adding up the load on the heli, the 922 servos pull 250 ma and tail servo 1 amp (Power HD 3688HB).
This is under normal load. I'm already at about 2 amps.
This doesn't include the Receiver and Gyro load.
I know the receiver will pull around 300 ma.
I learned this when I had the receiver on my bench, hooked it up to a SMALL 5v power supply and tried to bind it to my transmitter.
I could not get it to bind.
After much trial and error, I discovered I had the current limit on my power supply set to 200 ma.
Cranked the limiter up to 350 ma, watched the current meter and I was surprised at how much current these receivers were pulling.

Anyway, I'm leaning towards the BEC as being the problem, but I'm still going to tear this thing apart and check connections.

Don

 

[Lee]

If you lost power to the RX does it not show you having a brown out with a flashing light on the RX?
I see you are using a 9X and DSM2 Orange RX. So you have the Spectrum Module in the X9? Maybe there is something to do with the module to RX? Just a guess.

 

[DoninIA]

Good point Lee.
That's one of the things I noticed after my problem.
The LED was still solid (not flashing).
So I think if it was a current issue, that led would be flashing.

I think I will still convert over to the YEP ESC's though, but now I better take a harder look at the connections.
Hopefully they will arrive here. Just received my latest HK order.
2-canopies, 2-MEM's Gyros and 2-Orange receivers.
Only thing in the box was 2 canopies. Let the fun begin.

Don

If you lost power to the RX does it not show you having a brown out with a flashing light on the RX?
I see you are using a 9X and DSM2 Orange RX. So you have the Spectrum Module in the X9? Maybe there is something to do with the module to RX? Just a guess.

 

[Lee]

The YEP esc is awesome. I love mine in my Warp 360.
Well that sucks about the missing parts.

 

[Tony]

If Lee trusts the YEP 45 in his Warp (a $400 frame), then I think I can trust it in my little ole Align lol. Hope you get it working soon.

 

[DoninIA]

Didn't have time to look at the 450 today. Planning on it tomorrow.
YEP ESC's are coming from HK USA warehouse, so hopefully in a couple weeks I will have them.
In the mean time, I am going to pull the receiver out.

Don

 

[DoninIA]

Started tearing into the HK450 heli and have already discovered one big problem.
I am using a HK 7ch Orange receiver. Opened up the case and the antenna fell on the bench.
The antenna has a very small jack that plugs into the circuit board.
With an vibration at all this antenna will unplug.
The end that flops around in the case is metallic and free to short out traces and components on the receiver board.
I have a couple more of these receivers ordered, the first thing I will do when I get these is secure that connection.
My next decision is how to secure it. Hot glue or Solder.
I think I will solder so it can be taken apart in the future if need be.

Don

 

[Tony]

Use hot glue. If there are two polls on that plug, and you solder it, then it will fail. Hot glue is nonconductive so it won't mess with any signal quality.

 

[DoninIA]

I ended up soldering it. There are 2 pads on the sides of the connector.
I rang them with my ohm meter, both go to ground.
I just soldered the one pad to the shield on the connector. Fairly simple.
Can be easily de-soldered if need be.
I will say, this is a quality coax connector, but I don't think it should be plug on. Maybe some type of screw on.

My next project will be to check all my receivers for this type of plug.
If the wind lays down tomorrow, it will be time for a test spin up and see how it goes.

Don

 

[Tony]

Good luck.

 

[Lee]

Glad you found the issue. I always hot glue my antennas in smaller RXs. In bigger ones, i protect them with plastic control rod sleeving.

 

[DoninIA]

I think I will try hot glue on the next one.
Is there any concern that the will act as a conductor and cause a short ?
Now if the wind would quit blowing.....

Don

- - - Updated - - -

Should say, is there any concern that the GLUE will act as a conductor and cause a short.

 

[Lee]

No definitely not. On the HK401B gyros we used to coat the circuit boards in glue to stabilize the gyros.

 

[DoninIA]

Thanks.

Don