[vbvabuster]

My PKE is going through servos at an alarming rate. I finished it a week before halloween 2010 so it hasn't been in use for that long of a time. It is a hyperdyne board. The left servo died on Oct 30, I was having trouble with that servo anyway and I had a spare so I didnt think much of it. Now today my right one died and by died I mean that they work when they want to and jerk from up and down. Now anyone who's built one of these knows that each servo is about $30 including shipping, which is expensive to replace multiple times. So Im just curious if this has happened to anyone else?

At least Mattel's comes out in December.

[Kingpin]

There's been a number of reports about the servos and how they act in relation to the kit, usually reports of being very jittery... even the servos I got with my Hyperdyne kit jitter a little the moment it's switched on.

[GhostGuy]

I suspect the issue is a combination of the brand of servo being used, and the method by which the wings are attached. I've heard of others having the same problem with his kits.

In regards to the brand of servo, Hyperdyne uses Cirrus CS101s in his kits as they are one of the only servos small enough to fit in a location where you can mount the wings directly on them. But Cirrus servos are cheap, and I've seen lots of reports of them burning out, not just in PKEs but also in remote control vehicles.

You say you've been paying $30 for them, but that's probably because you're buying directly from Hyperdyne. You can get them here for $15:
http://www.hobbypeople.net/index.php/ci ... servo.html

Lastly, in regards to the mounting method, mounting the wings directly on the servos as he reccomends is bad because it puts sideways force on the axle, and that makes the motor work a lot harder than it needs to and can make the gears bind up. If you've ever looked at the inside of the original PKE, they mounted the servos in the center of the PKE and used pushrods to attach the servos to the arms. I designed my own PKE kits to use this attachment method to hopefully solve the problem of servos burning out.

[vbvabuster]

Thanks for the help guys. @ghostguy I have been using cirrus cs101s I bought them from gravesrc.com for $19.99 + $8 shipping I just rounded it to $30, thanks for the link I'll buy them there for now on. I have been mounting the wings on the servos. I'll try to see if I can put the servos in the center, but my 9volt is positioned there and its already tight in there. I'll buy two new servos and use my PKE as a show piece and grab a few of mattels for halloween and cons.

[GhostGuy]

The 9v can fit in the handle of the PKE.

[vbvabuster]

I'll have to grind out the inside of the handle to make it fit. Im going to take it apart when I have the time. I didnt get the best shell to begin with, but I'll make it work.

[exo95er]

Yeah, it's an extremely tight fit to have the wings directly on the servo. My servos twitch too, so I ended up disconnecting them and manually operating the wings - pushing them up with my other hand.

[ChapterMasterTu'Shan]

Buy JR or Futuba servos. You get what you pay for, and these are much higher quality than Cirrus.

[vbvabuster]

@ ChapterMasterTu'Shan, Im afraid I haven't heard of JR or Futuba. Do you use them in yours? Also do you know the model numbers? thanks.

[ChapterMasterTu'Shan]

I don't know how they are suddenly so cheap, but:

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXNCV6

[vbvabuster]

Thanks, Im going to order two right now.

[ProtonCharger]

everytime i see this thread i read "vbvabuster" as "vulvabuster."

[vbvabuster]

Lol. I knew I should have picked a different name when I signed up.

[Cyland Props]

Oddly enough the cheaper analog standard size servos seem to be much better suited to the PKE meter than the more pricey digital servos of any size. Typically the slower the servo the better it works.

[jaguargod]

There's been a number of reports about the servos and how they act in relation to the kit, usually reports of being very jittery... even the servos I got with my Hyperdyne kit jitter a little the moment it's switched on.

That "power-on" jitter is pretty normal. Every R/C car that I have ever had did that.

[jimbo7]

I seperated all the wires on the ribbon cables going to the wing boards on my kit. They move much easier which will also allow your servos to live longer. Atleast, I have had lots of luck going that route.

[GhostGuy]

It's impossible to prevent the servos from moving at all when they power up. The arms will inevitably have moved slightly out of place while the prop was powered off, and in addition it takes the microcontroller bit longer than the servos to power up and start sending commands to them.

That said, if you're getting lots of jitter when they power up, then yes, that's bad. On my kits for example, the servos only move twice when they power up. They don't sit there and shake. Shaking might be a sign of the servo trying to move farther than the PKE arm will allow it, so it is binding up and unable to move to the position it wants to. If that's happening you might try removing the servo horn and turning it a bit so the rest position the arms try to move to when the pke first powers up isn't inside of the PKE body where they can't go.