!!3 dead DS76t's within 3 hovers!!

[grabsomeozone]

short and to the point. I've been flying Helis since last march. MY 300X HAS BURNT UP THREE TAIL SERVOS IN NOT EVEN THREE FLIGHTS. They all have gone out within about 30sec of lift off(haven't even switched batteries yet). I'm using the stock DS76T w 1520center pulse and 270hz frequency(100% sure 7200 is set up right, i've even quadruple checked this) . My endpoints are all set w no hint of binding and pushrod to tail slider is perfect. I also have a 450x and have done the 7200BX set up multiple times w no issues. all of the cyclic servos are working perfectley and have never even had one act funny nevermind go dead. i think its something w the 7200 and will problably call HH to see if i can send it in. The servos have died in low level hovers so haven't had any crashes as a result(sure is helping my reflexes though). when i check them(DS76T's) they are cool to the touch and not even warm. i think its the 7200 and was hoping for some ideas and/or confirmation of my thoughts. almost everything i've learned about helis hsa come from this site. THANK YOU ALL FOR YOUR HELP. YOUR GREAT.
Ricky Bedard(southern NH)

[nartac]

posts like this is the reason why after 2 flights on my new 300x, I switched out to Hitec servos for both cyclic and tail. Just don't want to chance it.

[dragon79]

Originally Posted by nartac

posts like this is the reason why after 2 flights on my new 300x, I switched out to Hitec servos for both cyclic and tail. Just don't want to chance it.

Hey Cain, are those servo model numbers listed in that post for "building a sticky" ? Just curious. Mine still good but always good,to have a reference post like that.

[melow08]

I also switched mine out BEFORE there was an issue, just in case. I have the 5065's on the cyclic and 5084 on the tail, works great, not really better or worse than the originals, but metal gears and no reported problems for all the time they have been in service.

[DoubleCH]

I wouldn't jump to conclusion yet, especially when 3 servos failed in short order. I may very well jinx it but my original stock tail servo has served almost 150 flights and 1 BEC voltage dip crash and a pilot error crash that actually pushed the servo out of alignment with pushrod. Servo still works fine.

Sounds like OP knows what he's doing. Is any of the DS76t's that get burnt up an existing one from the 450X? How do you define "burnt up" especially when you say they never got warm? What happens if you try run them on the 450X? Have you checked BEC output voltage (easiest point to check is servo plug exposed metal on the side of BX.

[nartac]

Originally Posted by dragon79

Hey Cain, are those servo model numbers listed in that post for "building a sticky" ? Just curious. Mine still good but always good,to have a reference post like that.

yes, I have a set of Hitec HS-5065MG for cyclic as a spare for my 450 pro and an HSG-5084 in hand for the tail so I just threw them in. Perfect fit no mods necessary except for the elevator where I have to file the servo arm a bit to clear the wicked motor.

[trippledigitss]

I just had my stock tail servo go out today. I had probably 25-30 flights on it since new and flew two batteries today with no trouble. Then when I put a 3rd batt in and went to lift off she spun around me. So I set it down and then noticed the tail was stuck in full left rudder beyond normal travel. I popped it loose to the middle but the servo is dead, wont move at all and was pretty warm to the touch. Thinking back I heard a snap/pop when I plugged in the 3rd batt but I thought it was just an arc or something from plug to plug, maybe it was the t servo?. Anyway, no damage and just ordered a new stock one, gonna call HH and see if they will send me one, but for $15, the servo is no big deal, its the cost of a crash caused by it that would have irked me.

But I decided to look on here to see what a suitable upgrade would be for it with minimal or no mods required. I've never used HiTec's and my personal feeling about them is not favorable, not for any reason other than I dont really like the name. But are they a good servo? How do they stack up with other high end servos? I guess they cant be any worse than the Eflite huh? I may try that 5084 nartac mentioned, looks like they are only 30-40 bucks?

[nartac]

Originally Posted by trippledigitss

I just had my stock tail servo go out today. I had probably 25-30 flights on it since new and flew two batteries today with no trouble. Then when I put a 3rd batt in and went to lift off she spun around me. So I set it down and then noticed the tail was stuck in full left rudder beyond normal travel. I popped it loose to the middle but the servo is dead, wont move at all and was pretty warm to the touch. Thinking back I heard a snap/pop when I plugged in the 3rd batt but I thought it was just an arc or something from plug to plug, maybe it was the t servo?. Anyway, no damage and just ordered a new stock one, gonna call HH and see if they will send me one, but for $15, the servo is no big deal, its the cost of a crash caused by it that would have irked me.

But I decided to look on here to see what a suitable upgrade would be for it with minimal or no mods required. I've never used HiTec's and my personal feeling about them is not favorable, not for any reason other than I dont really like the name. But are they a good servo? How do they stack up with other high end servos? I guess they cant be any worse than the Eflite huh? I may try that 5084 nartac mentioned, looks like they are only 30-40 bucks?

I have been using hitec hs-5065mg on my 2 450 pros for the past year and half and have never had them ever malfunction. I have also crashed them few times and most of the time the metal gears held up fine though I have replaced the metal gears a few times. The 450's have futaba 9257 tail but since I have this 5084 sitting around, I threw it in and it works great so far.

If you decide to go with an aftermarket servo, make sure to go over the setup to make sure the servos function as it should. This means mechanical setup as well as go through the AR7200bx setup.

[DoubleCH]

Originally Posted by DoubleCH

I wouldn't jump to conclusion yet, especially when 3 servos failed in short order. I may very well jinx it but my original stock tail servo has served almost 150 flights and 1 BEC voltage dip crash and a pilot error crash that actually pushed the servo out of alignment with pushrod. Servo still works fine.

Jinxed indeed.
https://www.helifreak.com/showthread...34#post4927634

[sn00p]

Originally Posted by DoubleCH

Jinxed indeed.
https://www.helifreak.com/showthread...34#post4927634

I chuckled to myself when i was reading your above comments as i had not long read your flight log lol.... thats mine jinxed now too

[grabsomeozone]

one of the servos that died was the origanal that came on my 450x. i cant check the voltage coming out of the BEC as i dont have a device to test it. i thought that the voltage output may have spiked as well so i put a H3000 spare that i had on it as i know they can handle higher voltage(set to 1520CP and 50HZ on the 7200BX. there is a chart in the 7200manual w tail settings. 65 isnt an option but i heard that servos can be ran at lower HZ w/o damage but not higher.) i also know that its not a tail servo but wanted to try it for the above reasons. that to got burnt out. I guess thats bad term to use. they were dead w no response or sound at all and only at ambient temp when touched. i've tried the dead servos on the 450's 7200 and no response. i dont know what to do next? I don't believe that i had 3 bad DS76t's and a H3000? i was going to try the 5020G off the 450 out but thats a little pricey to risk as i am not currently working. like i stated before, "never had a problem on the cyclic". wouldnt a high voltage supply have effected a 6.0 volt cyclic servo if i killed a 6.0volt tail servo in under 30secs? any and all thoughts welcome. i dont want to buy a pricey tail servo and have it go to shit ya know.

[ahahn]

Originally Posted by grabsomeozone

...<snip>... i cant check the voltage coming out of the BEC as i dont have a device to test it. ...<snip>...

If you think that you will be flying electric helis (or planes), I really recommend getting an inexpensive multimeter. Sometimes you really need to know what is going on.

Think of it as a tool, equivalent to a good set of hex drivers!

[DoubleCH]

Originally Posted by grabsomeozone

i dont know what to do next? I don't believe that i had 3 bad DS76t's and a H3000? i was going to try the 5020G off the 450 out but thats a little pricey to risk as i am not currently working. like i stated before, "never had a problem on the cyclic". wouldnt a high voltage supply have effected a 6.0 volt cyclic servo if i killed a 6.0volt tail servo in under 30secs? any and all thoughts welcome. i dont want to buy a pricey tail servo and have it go to shit ya know.

You mean the 6V-capable H3000 also dies? This is weird. I wouldn't try an expensive tail servo in that case. Maybe get another stock cyclic servo to use as tail for testing for now. At least you get a spare cyclic servo once testings are done.

[trippledigitss]

Originally Posted by nartac

I have been using hitec hs-5065mg on my 2 450 pros for the past year and half and have never had them ever malfunction. I have also crashed them few times and most of the time the metal gears held up fine though I have replaced the metal gears a few times. The 450's have futaba 9257 tail but since I have this 5084 sitting around, I threw it in and it works great so far.

If you decide to go with an aftermarket servo, make sure to go over the setup to make sure the servos function as it should. This means mechanical setup as well as go through the AR7200bx setup.

Thats good to know about your experience with the Hitec's. I called HH today and they are going to send me out a new one for free. But I had already bought a replacement eflite right after my first post, I was ordering a bunch of servos for my goblin 500 build and just figured $15 for the eflite tail servo was no big deal. I should have just got the hitec, cuz now I dont want to just place an order for that one thing so I'll probably just wait until I need something else. Or maybe if/when I burn through these other 2 eflites? Then again I was lucky to have it go in between flights and not cause any damage so maybe I should just get the hitec or another servo that is better than the stock one and change it out before I have any issues with it.

The guy at HH said it is not a common problem they are running into at all, he said maybe only 2 others have called with a problem with the tail servo?

Anyway, thanks again for the info!

[trippledigitss]

Originally Posted by ahahn

If you think that you will be flying electric helis (or planes), I really recommend getting an inexpensive multimeter. Sometimes you really need to know what is going on.

Think of it as a tool, equivalent to a good set of hex drivers!

Yeah +1 on that, get a tester/meter. Then I would think about sending the BX back to HH and have them send you out another? Either way, good luck, hope you figure out what is up and get it all fixed up and in the air again.

[grabsomeozone]

yeah i have about 20 DS76's with stripped gears around. when i first got the 450x i didnt realize they could be rebuilt. i have one on the tail now but havent got around to trying it out(replaced the gears). its all set up though. going to look around for a meter. i actually may have one. i have all kinds of strange tools around from working in the various construction trades. on which of the three servo tabs that come out of the 7200 should i place the testing probes or doesn't it matter.(just try different combos till i get a reading?)

[sn00p]

Originally Posted by sn00p

I chuckled to myself when i was reading your above comments as i had not long read your flight log lol.... thats mine jinxed now too

FFS it did indeed jinx me

[DoubleCH]

Of all who got jinxed who has the highest flight count on the tail servo before jinxed? I got 150+ flights.