dx7 and the famous DS821 servos
04-20-2009 | 04:23 PM
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From: banbridgenorthern ireland, UNITED KINGDOM
dx7 and the famous DS821 servos
Just flew the new Great Planes Extra 300SP only for it to crash within 3-4minutes...elevator servo (the famous DS821 JR servos) locked on its first use and is seized solid! STAY AWAY from these servos. JR really ought to admit the problems with these servos. Now i have a plane smashed for a failure of the elevator - plane is amazing though - rolls like mad on low rates. lets see what horizon hobby will say about refunding my plane and also replacing all the servos...
04-20-2009 | 04:40 PM
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From: banbridgenorthern ireland, UNITED KINGDOM
RE: dx7 and the famous DS821 servos
they would be for the money but alot of people have had probs with them. cant believe they have resulted in a wrecked plane [:@] lol
04-20-2009 | 04:41 PM
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From: West Valley City, UT
RE: dx7 and the famous DS821 servos
I have to agree with gaRCfield. I have a couple planes with them and have never had an issue. I fly the hell out of the planes too. I guess you just got unlucky and received a bad one. Sorry to hear you lost your plane.
Anyone at any time from any manufacturer could have this happen.
Anyone at any time from any manufacturer could have this happen.
04-20-2009 | 04:46 PM
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From: banbridgenorthern ireland, UNITED KINGDOM
RE: dx7 and the famous DS821 servos
but really should horizon hobby be responsible for this as really it is unacceptable for it fail immediately and also result in a bust plane!
04-21-2009 | 12:07 AM
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From: Elmwood Park ,
IL
RE: dx7 and the famous DS821 servos
I am assuming everything including the servo that locked on you during the preflight checked out ok ? you did do a preflight check right ?
04-21-2009 | 01:13 AM
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From: St Peters,
MO
RE: dx7 and the famous DS821 servos
I had 2 of the early version ones shear the shaft off. Replaced them with standard Jr servos and have not had a problem since. When I called HH, they tried saying I must have had them in a bind and although they offered to replace them, I declined. Luck for me they both sheared while the plane was on the ground so I suffered no damage.
Jr
Jr
04-21-2009 | 07:57 AM
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From: Sambach,
AE, GERMANY
RE: dx7 and the famous DS821 servos
I use DS281's in my GP Reactor and I love them! I got a smokin deal on a set of four so I slapped them in the Reactor and have been using them for about a year now. It really is a great servo. I am sorry to hear you crashed your plane. It sounds like you got a bad servo.
04-21-2009 | 09:47 AM
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RE: dx7 and the famous DS821 servos
ORIGINAL: rsands2801
Just flew the new Great Planes Extra 300SP only for it to crash within 3-4minutes...elevator servo (the famous DS821 JR servos) locked on its first use and is seized solid! STAY AWAY from these servos. JR really ought to admit the problems with these servos. Now i have a plane smashed for a failure of the elevator - plane is amazing though - rolls like mad on low rates. lets see what horizon hobby will say about refunding my plane and also replacing all the servos...
Just flew the new Great Planes Extra 300SP only for it to crash within 3-4minutes...elevator servo (the famous DS821 JR servos) locked on its first use and is seized solid! STAY AWAY from these servos. JR really ought to admit the problems with these servos. Now i have a plane smashed for a failure of the elevator - plane is amazing though - rolls like mad on low rates. lets see what horizon hobby will say about refunding my plane and also replacing all the servos...
I don't know your experience level (not a slam..so don't take that wrong) but set up, binding, and so on, are a major cause of some problems that are attributed to servos but are actually due to linkage problems than they are to the servo.
I did break one micro servo by playing with it when it was on the plane.. I broke a tooth inside the servo gearing which did cause it to lock up, but that was my fault, not the servo. The small servos are quite delicate, and I have occasionally been described as a bull in a china shop..
but proper set up of the linkage is paramount to battery life and servo "abuse".CGr.
04-21-2009 | 03:47 PM
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From: banbridgenorthern ireland, UNITED KINGDOM
RE: dx7 and the famous DS821 servos
a few on heli side of things have had probs with gears stripping in flight. I made sure there were no binds - its my 4th plane built so well aware of binding, etc. I was flying on low rates so binding was impossible during flight. i make sure before every flight that i do a preflight check on the surfaces, linkages and listen out for any binding from each servo and ensure it isn't trying to constantly drive.
04-21-2009 | 03:48 PM
#12
RE: dx7 and the famous DS821 servos
ORIGINAL: CGRetired
I have eight of them on two different planes and not a one has given me a problem. How many have you heard have had problems? I've not heard a thing here on RCU about problems with these servos, especially with any seizing up.
I don't know your experience level (not a slam..so don't take that wrong) but set up, binding, and so on, are a major cause of some problems that are attributed to servos but are actually due to linkage problems than they are to the servo.
I did break one micro servo by playing with it when it was on the plane.. I broke a tooth inside the servo gearing which did cause it to lock up, but that was my fault, not the servo. The small servos are quite delicate, and I have occasionally been described as a bull in a china shop.. but proper set up of the linkage is paramount to battery life and servo "abuse".
CGr.
ORIGINAL: rsands2801
Just flew the new Great Planes Extra 300SP only for it to crash within 3-4minutes...elevator servo (the famous DS821 JR servos) locked on its first use and is seized solid! STAY AWAY from these servos. JR really ought to admit the problems with these servos. Now i have a plane smashed for a failure of the elevator - plane is amazing though - rolls like mad on low rates. lets see what horizon hobby will say about refunding my plane and also replacing all the servos...
Just flew the new Great Planes Extra 300SP only for it to crash within 3-4minutes...elevator servo (the famous DS821 JR servos) locked on its first use and is seized solid! STAY AWAY from these servos. JR really ought to admit the problems with these servos. Now i have a plane smashed for a failure of the elevator - plane is amazing though - rolls like mad on low rates. lets see what horizon hobby will say about refunding my plane and also replacing all the servos...
I don't know your experience level (not a slam..so don't take that wrong) but set up, binding, and so on, are a major cause of some problems that are attributed to servos but are actually due to linkage problems than they are to the servo.
I did break one micro servo by playing with it when it was on the plane.. I broke a tooth inside the servo gearing which did cause it to lock up, but that was my fault, not the servo. The small servos are quite delicate, and I have occasionally been described as a bull in a china shop..
but proper set up of the linkage is paramount to battery life and servo "abuse".CGr.
04-21-2009 | 03:49 PM
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From: banbridgenorthern ireland, UNITED KINGDOM
RE: dx7 and the famous DS821 servos
the servo wasnt trying to even drive when i landed from what i could see - just jammed solid and close to its centre position
04-21-2009 | 08:04 PM
#15
RE: dx7 and the famous DS821 servos
Equipment fails. You fly long enough and its going to happen. I had a JR 537 fail on the elevator of one of my planes. Is a jr537 a bad servo, I doubt it, just bad luck. Get over it and move on or you will be out of the hobby in a short period of time. Most electronics fail very quickly after you start using it, if thier going to fail. Some guys burn in their equipment before using it. Dual elevator servos may have helped, You may want to look into a more redundant setup in the future.
04-22-2009 | 03:46 PM
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RE: dx7 and the famous DS821 servos
Heli guys wont touch them because of the sheared shafts. I saw one go on the aileron of a 46 size extra, the output shaft came off the top gear.
I wouldn't put those particular servos in anything that costs more than the servos themselves.
Your milage may vary. Search them on a heli site, there's thread after thread about them shearing or dying.
I wouldn't put those particular servos in anything that costs more than the servos themselves.
Your milage may vary. Search them on a heli site, there's thread after thread about them shearing or dying.
04-22-2009 | 08:22 PM
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From: GraftonNew South Wales, AUSTRALIA
RE: dx7 and the famous DS821 servos
I have had a shaft break on a DS821 servo as, it seems, have a number of other people. I have since relegated the rest of the ones I got with my DX7 set to throttle servos.
Since the problem was never acknowledged I can only assume that there has been no fix, and hence would not buy another DS821.
Just my $0.02
Terry
Since the problem was never acknowledged I can only assume that there has been no fix, and hence would not buy another DS821.
Just my $0.02
Terry
