GY401 - Rudder servos are going bad after one flight
10-11-2014, 11:03 AM
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GY401 - Rudder servos are going bad after one flight
I have a Raptor 30 with a Orange FASST receiver and a Futaba GY401 Gyro. I have gone through 2 servos so far. It only goes up for a couple of flights and the servo stops working. It had been in a pretty bad crash before it started cooking servos. I thought the first one just burned out on it's own then a second burned out. These are rated for 6 volts and I have a Life 6.6 receiver battery. The tail slider does have a little bit of resistance I am going to rebuild the tail again. The resistance isn't bad enough to bur a 90 lb torque servo out though.
10-14-2014, 08:45 AM
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Sounds like a possible set-up problem to me as the GY-401 and proper servos will last for hundreds of flights.
First question is what servos are they?
Second: Did you set it up so mechanically so that you have pretty much equal throw of the servo arm when giving left stick as when giving right stick?
Third: If set as above, is the servo arm perpendicular to the control rod when at mid stick?
Forth: If all above did you adjust the end point pot to insure no binding at either full right or full left?
First question is what servos are they?
Second: Did you set it up so mechanically so that you have pretty much equal throw of the servo arm when giving left stick as when giving right stick?
Third: If set as above, is the servo arm perpendicular to the control rod when at mid stick?
Forth: If all above did you adjust the end point pot to insure no binding at either full right or full left?
10-15-2014, 08:06 AM
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I have a Raptor 30 with a Orange FASST receiver and a Futaba GY401 Gyro. I have gone through 2 servos so far. It only goes up for a couple of flights and the servo stops working. It had been in a pretty bad crash before it started cooking servos. I thought the first one just burned out on it's own then a second burned out. These are rated for 6 volts and I have a Life 6.6 receiver battery. The tail slider does have a little bit of resistance I am going to rebuild the tail again. The resistance isn't bad enough to bur a 90 lb torque servo out though.
10-15-2014, 08:15 AM
#5
Key points to his original post
a 401 is normally paired with a 9253 or a 9254
Those servos are rated at 4.8v (4 cell pack)
Anything more needs a voltage drop.
If he's flying one of those servos, then the increased voltage is almost certainly the issue.
But he hasn't addressed the questions I asked so we don't know yet.
a 401 is normally paired with a 9253 or a 9254
Those servos are rated at 4.8v (4 cell pack)
Anything more needs a voltage drop.
If he's flying one of those servos, then the increased voltage is almost certainly the issue.
But he hasn't addressed the questions I asked so we don't know yet.
10-15-2014, 11:02 AM
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The first servo it burned out was a Turnagy copy of the Futaba servo that comes with the GY401 Gyro the second was a Hitec HS-6635HB servo both can take 6.6 volts and
HS mode. I have never seen a Gyro burn out servos and this gyro has ben good for a long time with many different servos on it.
I did have the original 9253 start to smoke and went bad after 5 flights because I forgot about the 6.6 volts being too much for that servo. A lot of flyers said they run 6.6 volt life batteries with the 9253 with no problems so I thought it would work. But the rest have been 6 volt servos.
HS mode. I have never seen a Gyro burn out servos and this gyro has ben good for a long time with many different servos on it.
I did have the original 9253 start to smoke and went bad after 5 flights because I forgot about the 6.6 volts being too much for that servo. A lot of flyers said they run 6.6 volt life batteries with the 9253 with no problems so I thought it would work. But the rest have been 6 volt servos.
Last edited by Basil Yousif; 10-15-2014 at 11:06 AM.
10-15-2014, 01:31 PM
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The first servo it burned out was a Turnagy copy of the Futaba servo that comes with the GY401 Gyro the second was a Hitec HS-6635HB servo both can take 6.6 volts and
HS mode. I have never seen a Gyro burn out servos and this gyro has ben good for a long time with many different servos on it.
I did have the original 9253 start to smoke and went bad after 5 flights because I forgot about the 6.6 volts being too much for that servo. A lot of flyers said they run 6.6 volt life batteries with the 9253 with no problems so I thought it would work. But the rest have been 6 volt servos.
HS mode. I have never seen a Gyro burn out servos and this gyro has ben good for a long time with many different servos on it.
I did have the original 9253 start to smoke and went bad after 5 flights because I forgot about the 6.6 volts being too much for that servo. A lot of flyers said they run 6.6 volt life batteries with the 9253 with no problems so I thought it would work. But the rest have been 6 volt servos.
10-16-2014, 08:09 AM
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So I guess the real question is can a crash cause a GY401 to act like it's working and burn out servos. I just got another GY401 so I'll replace it. It would be a waste to not use the suspected bad one if it were good.
10-16-2014, 03:47 PM
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If it was working fine before the crash.. and started burning out servos after the crash then it is probably damaged.
Last edited by Rob2160; 10-16-2014 at 03:58 PM.
10-18-2014, 11:00 AM
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Got out my Amp/voltage testing harness out and tested the setup - The Gyro tested out good but the Orange receiver was bad. So I think the voltage problem was going on with the receiver. I will definitely try the GY401 out in a airplane to see if it's okey. If the rudder servo dies in a airplane I can still land the plane.
10-18-2014, 05:04 PM
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Got out my Amp/voltage testing harness out and tested the setup - The Gyro tested out good but the Orange receiver was bad. So I think the voltage problem was going on with the receiver. I will definitely try the GY401 out in a airplane to see if it's okey. If the rudder servo dies in a airplane I can still land the plane.
Some people were flashing different firmwares that helped but I didn't try it. I have no idea if the 2014 version of that gyro is any better.
I used to use the HK401 which is a GY401 clone in the early days and they were ok for learning but ended up swapping most of my helis to the Spartan Quark as my flying skills improved.
The difference is incredible. The Quark was king of the gyros a few years ago before FBL became popular.
They were over $100 back then, but now you can pick them up new for about $80. Treat yourself to one, I guarantee you will love it.
The heading hold is rock solid and it makes inverted flying and flips much easier - my 401s used to drift when inverted.
http://www.spartan-rc.com/products/quark/quark.php
Last edited by Rob2160; 10-18-2014 at 05:14 PM.
10-19-2014, 01:25 AM
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I heard the Spartan were great - the best bang for the buck. I need to get a couple. I also had a HK-401 it worked for 20 flights then started to go bad. The cheap mems for $11 seems to work okey. I don't do any extreme 3d anyway just go inverted and roll. Nothing crazy so the mems will be okey on electrics. My Raptor 30 - 50 and 60 though I will try out the Spartan.
10-19-2014, 07:17 AM
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With some of my HK401s they had a slight drift when upright during a hover. I was able to eliminate it by using a rudder trim that was pre set when I activated one of the idle up modes.
In upright flight the helis then had no yaw drift, however when inverted some of them would drift in yaw significantly. It wasn't consistent from one gyro to the next. The HK 401 was a $10 gyro and far from perfect. I had a few that were very good but most had slight drift issues and I replaced them with Quarks when I started doing more inverted flying.
The Quarks and the Genuine Futaba GY520 are totally drift free upright or inverted.
In upright flight the helis then had no yaw drift, however when inverted some of them would drift in yaw significantly. It wasn't consistent from one gyro to the next. The HK 401 was a $10 gyro and far from perfect. I had a few that were very good but most had slight drift issues and I replaced them with Quarks when I started doing more inverted flying.
The Quarks and the Genuine Futaba GY520 are totally drift free upright or inverted.
Last edited by Rob2160; 10-19-2014 at 09:37 AM.
10-19-2014, 08:33 AM
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I think the HK 401 was just not very good at taking crash shocks. That's where the quality comes in. I did do the mod where you open the case up and put in some hot glue with the glue gun. That helped a lot but sooner or later they went it went bad.
I think that's why some of these cheaper gyros fair well in electric helicopters - there's much less vibration than a notro.
I think that's why some of these cheaper gyros fair well in electric helicopters - there's much less vibration than a notro.
Last edited by Basil Yousif; 10-19-2014 at 08:36 AM.
10-19-2014, 08:39 AM
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Did fitting your new GY401 fix the problem?
Last edited by Rob2160; 10-19-2014 at 08:53 AM.
10-19-2014, 09:00 AM
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The only area the GY401 was weaker in compared to the top gyros was in how well it maintained the pirouette rate in the hover in severe winds (e.g. while flying sideways at a high speed and prouetting or while pirouetting while in a tail slide and similar tail demanding maneuvers. It would still do them fine, it is just that the piro rate would increase as the tail came into the downwind side and slow a bit wile going through the upwind side.
10-19-2014, 09:26 AM
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I have used a number of genuine Futaba GY401 gyros (and still do in some of my current helis, even some set for 3D) and I also tried the Hobby King clone. There was absolutely NO similarity in performance between the two. If the GY401 was an 8, the HK401 was a 2.
The only area the GY401 was weaker in compared to the top gyros was in how well it maintained the pirouette rate in the hover in severe winds (e.g. while flying sideways at a high speed and prouetting or while pirouetting while in a tail slide and similar tail demanding maneuvers. It would still do them fine, it is just that the piro rate would increase as the tail came into the downwind side and slow a bit wile going through the upwind side.
The only area the GY401 was weaker in compared to the top gyros was in how well it maintained the pirouette rate in the hover in severe winds (e.g. while flying sideways at a high speed and prouetting or while pirouetting while in a tail slide and similar tail demanding maneuvers. It would still do them fine, it is just that the piro rate would increase as the tail came into the downwind side and slow a bit wile going through the upwind side.
Last edited by Rob2160; 10-19-2014 at 09:41 AM.
10-19-2014, 03:44 PM
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I took the time to find out who the poster is and it appears he is always plagued with problems. I fly nothing but JR and they always tell the buyer what servo to use with their gyros and why. I believe Futaba does the same thing and my advice to the poster is to abide by what they recommend.
