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ACKopter · 03-21-2009, 02:33 PM

Swaped motors using a Common Sense R/C @ 3500 Kv w 13 T pinion and got a substantial increase in HS over the old 430X w/11T pinion but now have some gyro problems I cant overcome. This system is a 401 gyro w/ 9650 tail servo. Aside from my own lack of ability the heli has flown very well concerning the gyro function up to this point

The heli has a fairly sharp wag and a heavy yaw nose left at hover. I'm using a DX7 Tx and I realize these aren't true values but I have tried everything from 67 to 81 in my gyro gain menu with little effect.

In an effort to eliminate the problem I have done the following, Reset the tail servo and centered as per the Finless vid, resized the links on pitch slider and servo wheel, replaced the pitch slider assembly (tail shaft and bearings are less than 3 weeks old), replaced the plastic tail blades with known good set of CF tail blades. In addition I have recently upgraded or replaced the following components, ceramic mainshaft bearings, new main and auto gear with oneway bearing, nerw tail gear and bearing, and lastly a new belt. I believe the belt tension is good but am not certain.

It does seem that I have a high frequency vibration but I don't kow where it's coming from. Blades are CF and have been well balanced again as per the finless vids, tracking is very close but not perfect and as I understand it this should be acceptable.

I've been trying to get things sorted out since yesterday afternoon and have come up empty-handed and out of ideas. Feeling a little brain dead at the moment and can really use some help.
TIA,Chris

airjawed · 03-21-2009, 07:22 PM

Get rid of the vibration....spin it up without main blades and tail blades....it should run smooth like that....if not....then take off belt....that would narrow it down to the front end stuff...keep doing that till you find the vibe.

The drift if probably coming from the vibe.

Another thing is that when you increase the headspeed you have to decrease the gain.

dkapus180 · 03-21-2009, 08:37 PM

Are you using the stock esc ihad wag in my tail along with unknown rudder input on my behalf i still had a vibration that would make my heli twitch i replaced all bearings shafts and so forth i pull the motor and spooled up with motor in hand and felt a thumping in the motor so i went to the lhs they had no motor but a phoenix 35, so i bought it got it up and running and from what i can see in the dark all i need to make are some gain adjustments so what im saying is my esc could supply constant steady power to the motor. just my .02

ACKopter · 03-22-2009, 08:10 AM

airjawed,
I'll see if I can't isolate the vibe, I forgot to mention in my earlier post that I have also just replaced the main shaft, feather shaft, flybar shaft and head dampeners as well.

dkapus,
Yes, I'm using the stock 35x ESC. The LHS where I obtained the motor has been having very good success with this motor/ESC combo but you never know. If I cant run down the vibe source I do have an alternate ESC I swap out just in case.

ACKopter · 03-22-2009, 08:29 PM

Still no success.
I was able to isolate the vibration to the head and took a very close look to find the problem. Paddles were ever so slightly out of align and were a little unequal by .010", the flybar is equal though, the new dampeners seemed a little sloppy also so I installed the thick spacers and that tightened things up.
I redid the gyro this time in rate mode and adjusted the servo position till the tail held fairly well and then wen't back to HH with no luck. It seemed almost worse, I'm not at all familiar with gyro set-up so it is quite possible I did something wrong.

All in all I've spent the better part of the day checking, adjusting and testing to no avail. Still have a vibration and the heli wants to yaw very heavy to the left but I did slow down the wag by backing way down on the gyro gain(63 on the DX7).
I have not changed out the ESC as I was sure it was not the problem but I don't know what else it could be. It will have to wait for now as I'm through for the day at this point and once again fairly well frustrated with the finer points of these little heli's.

03-21-2009, 02:33 PM	#1 (permalink)
ACKopter Registered Users My HF Map location Join Date: Jan 2009	New motor + HS increase = Gyro problems. Swaped motors using a Common Sense R/C @ 3500 Kv w 13 T pinion and got a substantial increase in HS over the old 430X w/11T pinion but now have some gyro problems I cant overcome. This system is a 401 gyro w/ 9650 tail servo. Aside from my own lack of ability the heli has flown very well concerning the gyro function up to this point The heli has a fairly sharp wag and a heavy yaw nose left at hover. I'm using a DX7 Tx and I realize these aren't true values but I have tried everything from 67 to 81 in my gyro gain menu with little effect. In an effort to eliminate the problem I have done the following, Reset the tail servo and centered as per the Finless vid, resized the links on pitch slider and servo wheel, replaced the pitch slider assembly (tail shaft and bearings are less than 3 weeks old), replaced the plastic tail blades with known good set of CF tail blades. In addition I have recently upgraded or replaced the following components, ceramic mainshaft bearings, new main and auto gear with oneway bearing, nerw tail gear and bearing, and lastly a new belt. I believe the belt tension is good but am not certain. It does seem that I have a high frequency vibration but I don't kow where it's coming from. Blades are CF and have been well balanced again as per the finless vids, tracking is very close but not perfect and as I understand it this should be acceptable. I've been trying to get things sorted out since yesterday afternoon and have come up empty-handed and out of ideas. Feeling a little brain dead at the moment and can really use some help. TIA,Chris

03-21-2009, 07:22 PM	#2 (permalink)
airjawed Registered Users My HF Map location Join Date: Mar 2008	Get rid of the vibration....spin it up without main blades and tail blades....it should run smooth like that....if not....then take off belt....that would narrow it down to the front end stuff...keep doing that till you find the vibe. The drift if probably coming from the vibe. Another thing is that when you increase the headspeed you have to decrease the gain. __________________ Trex 450 Pro 3xDS410M + MKS8910A+, Align FBL head w/Microbeast, CC 45 Gov@ 3400rpm(max timing, outrunner mode), Scorpion 2221-8 on 14t, Edge FBL main and tail, CF boom, CC BEC @ 6V

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03-21-2009, 08:37 PM	#3 (permalink)
dkapus180 Join Date: Oct 2008	Are you using the stock esc ihad wag in my tail along with unknown rudder input on my behalf i still had a vibration that would make my heli twitch i replaced all bearings shafts and so forth i pull the motor and spooled up with motor in hand and felt a thumping in the motor so i went to the lhs they had no motor but a phoenix 35, so i bought it got it up and running and from what i can see in the dark all i need to make are some gain adjustments so what im saying is my esc could supply constant steady power to the motor. just my .02

03-22-2009, 08:10 AM	#4 (permalink)
ACKopter Registered Users Thread Starter My HF Map location Join Date: Jan 2009	airjawed, I'll see if I can't isolate the vibe, I forgot to mention in my earlier post that I have also just replaced the main shaft, feather shaft, flybar shaft and head dampeners as well. dkapus, Yes, I'm using the stock 35x ESC. The LHS where I obtained the motor has been having very good success with this motor/ESC combo but you never know. If I cant run down the vibe source I do have an alternate ESC I swap out just in case.

03-22-2009, 08:29 PM	#5 (permalink)
ACKopter Registered Users Thread Starter My HF Map location Join Date: Jan 2009	Still no success. I was able to isolate the vibration to the head and took a very close look to find the problem. Paddles were ever so slightly out of align and were a little unequal by .010", the flybar is equal though, the new dampeners seemed a little sloppy also so I installed the thick spacers and that tightened things up. I redid the gyro this time in rate mode and adjusted the servo position till the tail held fairly well and then wen't back to HH with no luck. It seemed almost worse, I'm not at all familiar with gyro set-up so it is quite possible I did something wrong. All in all I've spent the better part of the day checking, adjusting and testing to no avail. Still have a vibration and the heli wants to yaw very heavy to the left but I did slow down the wag by backing way down on the gyro gain(63 on the DX7). I have not changed out the ESC as I was sure it was not the problem but I don't know what else it could be. It will have to wait for now as I'm through for the day at this point and once again fairly well frustrated with the finer points of these little heli's.

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