Walkera HM60 B

Iced_E · Posted: Wed Aug 11, 2010 5:22 pm Post subject: Walkera HM60 B

Hi, I am a NEWBIE in this heli buisness. After a lot of thinking, I finally ordered a Walker HM60B spesial edition.
Anyone got experiance from this heli? How difficult is it to set it up for a rookie pilot??
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a quote from a guy in the lokal RC club; "I NEVER CRASH MY HELIES, I JUST LAND THEM REALLY, REALLY HARD" Smile

Proud owner of Walker HM60 B

akhileshgarwal · Charging Joined: 23 Aug 2011 Posts: 2

My son, a beginner to RC helis, chose to buy a Walkera 60#B[2,4 GHz] rc heli, which was too advanced for his skill level, and he promptly crashed it. I am into aeromodelling with some experience with beginner’s helis such as Blade CX 2, and as his father and comparatively more experienced aeromodeller, I wanted to impress him and am trying to fix it, but find I need a lot of help !

The first problem was that the receiver and servos would not respond to the transmitter. The system is 2,4 GHz. Thinking that the receiver went bad in the crash[transmitters rarely do], I bought a spare receiver, but it wouldn’t respond either, so I figured it was a binding problem. I used another 2,4 GHz transmitter and luckily it binded ! Now I’m using the original Tx and it binds. However, there are some problems with the TX. It is set up in mode 2[throttle LH stick], but rudder stick does not work, though rudder trim does. On RH side, the elevator stick works, but the trim doesn’t. I opened the Tx and found that old batteries remained in the Tx and leaked onto the rudder pot. I tried removing the pot, it is devilishly difficult. I checked the pot resistance, it is 5k and varies, which means the pot is working, but still rudder stick control is not. Are the stick and trim pots in the same voltage sensing circuit, ie are the stick and trim pots in series or parallel ? Why is it that it in case of rudder, the trim works but the stick doesn’t while in case of elevator the stick works but the trim doesn’t. Can this problem be fixed ?

The rudder trim works, but only when the rudder servo is plugged into the receiver directly. If the rudder is plugged into the WK-G011 Gyro and the gyro is plugged into the receiver rudder output, the rudder servo stops working. The Gyro LED comes on[quick flash, which means the gyro is in the process of initialization when the power is turned on] but then goes off[which means the gyro is in normal mode or the power is turned off]. If the rudder trim is adjusted , at some position, the led blinks twice[which means that a] the rudder servo bellcrank is being adjusted or b]the neutral position of the rudder servo has drifted, and the neutral position has to be reset]. With the gyro connected, the rudder servo does not work. Is the gyro bad or does gyro sensitivity and rudder mixing require adjustment ?

The next problem is that the main gear teeth were stripped and I replaced it. Unfortunately, while working on the Tx, I accidently moved the Mode selector slide switch, so the throttle function moved to the rh stick and the elevator function to the left hand stick. When I fired up, the rotor started off at medium speed and I did not know how to stop it. I discovered the cause by chance when I moved the RH elevator stick and found it controlling the throttle ! Luckily I did not have a serious accident, but the teeth of the main gear stripped again. I changed the gear again and this time I have lubricated them with grease.

Then I found the aileron servo was bad and changed it, using another small heli servo. But the direction of arm movement was opposite, so I had to open the servo and interchange the motor and pot wires. Luckily it now works in the right direction.

I tried to get the heli to lift off by adjusting the tail rotor pitch manually to keep it from turning too much, but the rotor shook/vibrated a lot, particularly when I increased throttle. I balanced the rotor blades by adding electrical tape near the cg[ the two blades were badly unbalanced] and it helped a lot in reducing the vibration. I checked the pitch adjustment by disconnecting the brushless motor and giving throttle. My understanding is that a beginner’s setting is -3 to 4 degrees at 0, +5,5 degrees at half throttle , and +9 to 10 degrees at full throttle. But I find that upto half throttle, there is no change in rotor pitch and from half to full throttle, the pitch does change to + 5 degrees or so. Is it a case of bad pitch adjustment or wrong programming of exponential ?

I adjusted the rotor blade pitch to 10 degrees at full throttle and was able to lift off by giving a sharp burst of throttle. But the rotor is not stable, it tends to tilt to one side and the direction of tilt moves around-I believe its called toilet bowl effect. Is it bad tracking or due to bad flybar adjustment ?
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akhilesh