fredycompean

Hi, please help me get around the electronics on this thing. I need to know how to program the ESC, how to know the amps I'm pulling and some minor things about the balancing and building.

Equipment:
TRex 450X
Align 400L brushless motor.
Align 25A ESC
6 ch Hitec Receiver
HS-55 Hitec servos (HS-50 rudder)
GY240 gyro
Align Li-poly 9c 11.1V 1800mAh batts.

Questions
1. My TRex is just finished. the only thing that went wrong during building was that I over threaded the paddle flybar control horns. I don't know which way would be best to fix that problem Maybe, using some CA to regenerate the thread??? please suggest.

2. The manual says to put the battery in front of the motor. I find it that its tight with the canopy and I'm not sure. it looks like it fits much better behind the motor. Has anyone tried this? Does it affect balancing?

3. When I connect battery to ESC, the motor emits sounds. I haven't yet found a friendly detailed manual for it. Please explain what I should do. I know it has three features you can configure, but I'm not familiar with them. Which settings should I use?

4. My main rotor only spins one way, does everyone's? How do I know my motor will run the way the main rotor needs it to rotate. If it was reversed and needed any one cable to be crossed, it would fight the way the main rotor spins, and maybe scrap the pinion or gear.

5. I've always wanted to know how many amps I'm pulling and never new how to do that. Today I came across this item at the bottom of the page http://www.align.com.tw/shop/index.php?cPath=22_35 and wondered if it would help. It's a mini amp clamp meter, mighty expensive so Please let me know if it works.

Please help. All is about done and my fingers are burning to maiden this baby.

Thanks in advance to any one that answers any of this questions.

FRedy

fredycompean

Oh, and one more thing.

Which pinion is best in your experience. i got three with my motor, and I can barely tell the difference and don't know which would be best.

tks

Norrmannen

You'll find all that you need here: http://trextuning.com/

fredycompean

Thanks, i'll take a look

fredycompean

Maiden this morning. It's good. Still a little tweeking to do. Those "z" bend push rods are giving me trouble on elevator control. Also I have some aileron trouble. I wonder if that upgrade of small ball links is a good idea.

Also please suggest which pinion to use with each different set of blades.

Fredy

Norrmannen

I'm pretty new to this and didn't notice a big difference. Setting dual rates tho made a big difference not so twitchy...

fredycompean

I'm having problems wth my control arm links hitting the SF mixing levers. Anyone have the same problem ? How was it fixed?

avi8er

1. nothing to suggest that I would stand behind, sorry.
2. Personally I am suspending my battery below the heli with pull ties, this way I can fine tune cg and have a big battery; 3s2p 2500. I am running the Align 400L and I have not heard a sound, are you sure it is not coming from the speed controller? Is your throttle trim all the way down? Some motors hum a little if they are getting juice but not enough to spin.
3. I will guess at the settings, this is a GUESS so find a manual; voltage should be 9 volts for a 3 cell lipo, there should be a solf cutoff at low voltage, and the third could be so many less important things, maybe a slow spin-up.
4. there is a one way bearing in the flywheel. This allows the copter to autorotate if the motor siezes. The 400L is very tight so it seems like it will not turn backwards, however it will with proper force. This is not bad for the motor but be carefull what you apply the force to (don't hold the linkages, try the rotor head) If the motor is hooked up backwards the flywheel will spin when the motor is activated and the rotor will remain motionless, harmless. Just try it at low speed and correct it if wrong.
5. Amp meters are helpful, but unless you plan on mounting it on the heli and having a friend put his head under the flying heli and read it to you, it is only good for static thrust. The problem with your ESC is the amperage it makes available for servos, not the motor. Too much draw from the servos and the board stops working (melts, ask me how I know). Hope your not too high up. I am flying with the 400L and 15 tooth pinion, I hovered my 2500mah battery for just under 10 minutes or 1/6 hours. 2.5 Amps (2500Ma*h) divided by 1/6h=15A. My heli is using 15 Amps to hover, it is crude but it gives you an idea. I have read people are using the 25s with no problem but I went with a 35 just for the fun of it. Like $20 more for insurrance and I can run nice strong servos.

Be careful with the battery you are using. It is good for 16.2 continuous Amps. I am pulling 15 to hover with a pretty similar setup. Forward flight will require fewer amps but if you do ANY aerobatics it will quickly exceed that. The only other thing I have to add is that I am new to helis so take this info with a grain of salt. I do have a fair amount of electric plank experience to draw from but I spend most of my heli time entering and exiting forward flight, I don't do any crazy stuff yet.

fredycompean

Thanks for that. I solved many of the issues, but I'm interested in how you calculated the amp draw during hover.

If I did the same calculation, it gives my battery pulling 10.8amps during hover.......

I can hover for just over 10min (1/6 or .1666), I'm using a 1800mAh Align, so 1.8 / .1666 = 10.80ams.

is this correct? because then that brings another question to mind.

Why I'm I struggling with the battery temperature?

Right upon landing I take my heat gun and meassure the temperatures and they read as follows:

Motor (align 400L) 199ºF
Align Battery 168ºF (on the side, but on the lable is like 20-30º less, don't know why)
Align 25A ESC 110ºF

I've been told that at that temperature, my battery shouldn't be over 140º so at 168º is over heating and that it will reduce it's life if continued that way. i thought overheating was caused by overdrawing amps, but at 10.80amp draw on a 16.20amp capable battery (rated at 9C 1800 mAh) it doesnt' seem that way. I'm only using 66% or it's current draw capacity and I'm over heating???

Can anyone figure that out? I'd appreciate it, because now I'm all confused. Also why does it read differently on it's side than on the labels side?

avi8er

I believe that these flat packs emit their heat outward through the sides first, measure wherever it is hottest. I don't have a heat gun but I have found this; my motor is HOT but I don't sizzle when I touch it so that is near 200f. I can squeaze my battery after flight and it is comfortably warm, about 110-120f. 140f you can not wrap your hand around the battery for more then a second. The speed controller is similarly warm.

Here is what comes to mind first about your battery, it is not holding a full charge. If you have a fancy heat gun you must have a multimeter. Check the voltage hot off the charger, it should be over 12 volts. I purchase the Triton charger when I got the $100 battery becauseI wanted to have all the info. When this charger is done it tells you the exact voltage on the battery and how many amps it pumped into it. I KNOW that I am using 2500Mah when I fly. If one of your cells starts to go bad the other two will draw faster, causing more heat and an inacurate calculation (it is a little inacurate to begin with so let's not get carried away).

Second, what pinion are you using, and what blades are you using? The carbon blades use a LOT more amperage to spin. The pinion also makes a big difference. I was using the 15t as per the manual, but I read at trextuning to use 13t. I had my friend with a lot more experience then me tell me that I need a smaller pinion, so I changed it and am waiting for the battery as we speak. And finally, are you hovering in ground effect or out? The Trex is in ground effect when below about 2 feet.

Norrmannen

Maybe your pitch is too high and not enough head speed?
Mine seems to raise in temp when I increase pitch..

fredycompean

Thanks, I do have the Triton too, and I know it's putting around 1750mAh into it. It's a 1800mAh pack, so pretty sure I'm getting the charge. Plus I have two packs, and they're both suffering from that heat. yesterday, at 6 minutes of hovering (both ground effect and not; intermitently) it was at around 120, which was good and got my hopes up, but I continued flying and when I saw my timer, it was at nearly 12minutes. I landed with out needing to, but just for safety of not over draning the pack, and it was at 148ºF. I'm gonna loosen up the belt drive a little.

I'm using the wood blades and a 13T pinion. I've also been to Trestuning.com and it has been great help, but still I can't resolve my issue.
I'm starting to think that it may be caused by servo power draw. I did mention I'm having problem with my collective on elevator control because the SF mixing levers are binding with the links at a certain position. I thought I had them on backwards, but have rechecked the manual and they are fine. I can't figure out why they bind.

I've done the canopy mod for battery heating, and also shaved flush the ailerons control arms to avoid binding with the canopy. there's still a lot of fine tuning to do to this heli. I definitely cant fly comfortable like this.

I have the pitch and throttle curve like suggested in the "set up" section of Trextuning.com so I dount it is the pitch - head speed relation. I've tried different settings and have tried a high headspeed with barely any pitch, but still the same.

I'll keep trying and let you know in case it helps somebody else with the same problem in the future.

Thank you for you comments

jamesotron

You're not alone there, I can quite easily get the aileron and elevator control horns to connect when extended to full throw. I've had to severely truncate the throw with EPA to stop it from touching. I also get binding where if I dial in max pitch extend the aileron to max throw in either direction and then reduce the pitch the swash plate can actually bind against the the top of the frame.

My main problem though is servo stalling, my HS-55's are constantly whirring trying to get the head to comply to their idea of center position. I've been around all the ball links with a soldering iron as suggested on trextuning.com and that has helped, but not relieved the problem. Any suggestions?

You're lucky, at least you have gotten in the air!