Ace GT5 causing ESC to get HOT and servos to twitch like crazy

[d2tw4all]

Maidened it today at the LHS in the driveway, shook like a bastard and turns out one of the blades was warped, luckily I was in the right place. Bought a set of align woodies for 10 bucks and threw them on and off she went, smooth as butter. Need to adjust blade tracking but I had no problems hovering it and doing some easy pitch pumps. Tail held well, during pitch pumps it moved and then corrected too much but I only had gyro gain at 60% so I'm guessing I just need to dial that up and I was so nervous I didn't bother switching to 100% on the gyro rate switch. I want to get it 100 percent mechanical before I do more, mainly just getting the blade tracking right but WOOHOO it was like butter in the air, I'm very happy! Thanks SO much for the insight here.

I only set my idle up to 85% since I have no idea what the headspeed is and I don't think the stock ace 40A ESC has a governer mode. I did download the iphone tach app so I'm assuming I can hit idle up while on the ground and keep the pitch at center and then use the app to determine the headspeed? Does anyone know if the stock ace ESC for this bird has governer built in? Otherwise I'd love tips for checking headspeed, seems like a 2 person job to be safe if you have to use a tach or the app...

I'm smiling!

Tom

[Bladecpnitro]

All right! Glad you got it going man.

I don't know how people are doing the cell phone app head speed test but it might be a good idea to put strait 50 50 50 50 50 in the pitch curves temporarilily and strap the heli down to check that.

Here is a headspeed calculator that runs within a few increments of what the iphone app does. Just punch all your info in on the top left and hit calculate. I think its more accurate if you leave efficiency at 90%.

For my 450 I punch this in:
11.1v lipo, 150 tooth main, 11 tooth pinion, 3850 motor kv)

http://dhrc.rchomepage.com/calcAdvanced.htm

[d2tw4all]

Thanks for the info. I flew it again yesterday, the gyro definitely acts up sometimes where it creeps for no reason, but if I power off/on it will behave. Not sure what the story is but at least I can get it to behave as long as I watch it when I power it on and make sure the servos aren't doing stupid things. The blade tracking looks like it's spot on now, so hopefully I can get more time on the bird and feel it out. Gyro gain def. should be at 100, when I flipped the gyro switch to that setting the tail held perfectly and there was no wag or hunting at all that I could see.

Tom

[d2tw4all]

I think I figured it out, you can NOT center your trims on the TX with the GT5, you need to look at the screen and adjust your trims so all the numbers are zeros. Mine were all not zero and I believe that's what was causing the servo drift.

Tom

[Bladecpnitro]

I installed my GT-5 last night a and the Align DS 415 MG elevator absolutely will not center at 90 degrees. Gary mentioned 90ing the servos good enough so as to not use anymore than 4 points of subtrim in the GT-5's servo subtrim menu. Mine is like 45 points if I leave it low and 49 if I shift the arm up one spline. The pitch and aileron aren't that far off..

I'm gonna have to have one longer swash link too, I had made one from a borrowed Blade SR rod that worked with the FB head after a crash but its just too short for the FBL head swash because the swash sets 5 or 6 mm's higher than the FB setup at center stick.


The other thing is gyro direction for the swash. I thought it would be easier to tell which direction its correcting when I lean the helicopter but the elevator servo barely moves at all. I think it moves the most if I roll the heli to the left.

What did you use for level reference when working with the pitch gauge?
Near as i can tell I have 5 degrees of negative pitch on the blades at center stick and 5 positive and 15 negative.

If I can get a few of these things corrected I'd be ready for a spool up this morning.

[d2tw4all]

I tried using a standard pitch gauge to which I attacked a bubble level, but then I got an align digital auto leveling pitch gauge and that got me where I needed to be in short time as far as pitch goes. I haven't messed with the other stuff yet, just been flying it as is and so far it's working fine. I'll probably go through the steps in the spring when it's warmer but for now it flies the way it is so I just run it.

Tom

[Bladecpnitro]

I borrowed another longer link off my SR which was too long and had to be cut down some. Got it all setup and found the problem with gyro swash correction was that I had my gyro mounted 1/4 turn out which meant the gyro was seeing left and right roll as elevator movement. Yes I wasted that nice gyro tape that came with the gyro and had to move my gyro a 1/4 turn. It was perfect where I had it. Now I can't unplug anything without taking the gyro off which might be a good thing. After moving the gyro a 1/4 turn it started acting right then. Swash corrections were what I was expecting.



I flew it this morning and love it.

[Laurens]

Thats good news! Sometimes small errors can cause big issues.

[Bladecpnitro]

Hey Laurens, is there a list of error messages somewhere for the GT-5?

[gwright]

After experimenting with numerous mounting tapes a while back, I found the thin grey tape that comes with the unit to be the best by far. There is a roll of thin grey tape sold by 3M, forget the number but it's available at most lowe's and wal marts. I'm not sure if it's the exact thing as what comes with the gyro but it works just as well and it's available locally. 3M has the thin grey stuff and some slightly softer clear stuff, almost like the gel pads. The clear stuff doesn't work as well so you want the grey.

[Laurens]

There's no special way for the GT5 to tell you there's a problem. For instance, what I've found is that if you don't use a second satellite, it just won't work.

@ Gary,
I'd be interested in that number, since we don't have any walmarts or lowe's around here.

[d2tw4all]

Originally Posted by Laurens

There's no special way for the GT5 to tell you there's a problem. For instance, what I've found is that if you don't use a second satellite, it just won't work.

@ Gary,
I'd be interested in that number, since we don't have any walmarts or lowe's around here.

I only use 1 sat, on spektrum, and it works just fine...

Tom

[Laurens]

Thats strange. Thinking of it, maybe I plugged it in the wrong port, but I'm not sure...

[d2tw4all]

Originally Posted by Laurens

Thats strange. Thinking of it, maybe I plugged it in the wrong port, but I'm not sure...

Maybe, all I know is mine works just fine with 1 sat. It's the first version too.

Tom

[Bladecpnitro]

Is this the 3M tape your talking about Gary?

http://www.price2watch.com/sears/com...ner/p/10502375

Originally Posted by gwright

After experimenting with numerous mounting tapes a while back, I found the thin grey tape that comes with the unit to be the best by far. There is a roll of thin grey tape sold by 3M, forget the number but it's available at most lowe's and wal marts. I'm not sure if it's the exact thing as what comes with the gyro but it works just as well and it's available locally. 3M has the thin grey stuff and some slightly softer clear stuff, almost like the gel pads. The clear stuff doesn't work as well so you want the grey.

[Nivenmo]

I am also using the HS-81 servo on a Mini Titan. However, the helicopter spins wildly during spool up. Could you share your setup parameters for this tail servo.

Thanks

Originally Posted by d2tw4all

Hi guys,
I'm having trouble setting up my mini titan with the FBL conversion and the GT5. Got the head all together and installed and now I'm trying to get the GT5 going and it's scaring me, I'm using 3 HS-65HB servos for swash and an HS-81MG for the tail. I don't fly 3D at this point and I saw another thread where someone was using this configuration on a GT5 FBL mini titan without any problems. I have everything bound through a spektrum Sat to my DX8, didn't have any problems there, and I set up the basic config for swash etc, but when I plug in all my servos and it turns on, they all buzz pretty bad and none of them will center on their own, it's weird all the servos seem to respond to my inputs but stay at the extremes, they don't follow my stick movements except outwards if that makes sense, and I noticed after fiddling with it for a minute or so that the ESC was getting HOT which since the motor isn't even connected tells me the BEC is pulling a LOT of juice. Anyone have any ideas? I haven't switched anything from the defaults except set the swash to 120, radio to spektrum and bound, and the servo frequency is 166. I'd love some advice here because the manual is useless and I have no experience with FBL and 120 degree helis... HELP!

Tom

[Laurens]

Ovrclkd had the same issue, this was his solution:

You need to change the Gain Direction for the Gyro tail sensor in the directional menu under rudder. Ok ..... time to maiden after the wind drops below 20 mph!