ds821 for tail?

[busa 2002]

can you use a ds821 for tail.or does it need to be digital

[nexgen]

Digi is always better especially if your gyro is digi only. Big things are speed and torque (in that order), you want as much of each as you can get. Digis will have more of both than a comparable analog

[MartinS819]

DS821a are digital servos, but yes speed is big when you consider tail servos. Usually rudder servos don't have as much torque as cyclic servos. The DS821s are OK, but when I used to use one it wouldn't always hold, especially in backwards flight, probably because they are relatively slow, and too slow for the Spartan. It did work fine with my ole GY401 though. Align makes some pretty good servos that won't break the bank, and they're fast. There's a similar thread a bit further down you can read that asked the same question.

[MartinS819]

Here you go:

http://helifreak.com/showthread.php?t=166863

[bobbybe]

martin-
i use the align ds610 servos for cyclic, and they're about as good as you can get for a coreless digital servo (.08 seconds and 12 KG of torque!!) under $60. they make a tail servo too- the ds620. but looking at those specs even a 610 would be fine for the tail

[MartinS819]

Yup, and they just came out with the new rudder servo, the DS650. Supposed to be the fastest right now. On the other end I hear JR will be releasing the new 8917s which are better than the 8717s, but cost a whopping $150 each!!! But unless you're Alan Szabo or Jason Bell, you won't even notice a difference.

[bobbybe]

.001sec and 1,000kg of torque! for only the price of a small car!

[MartinS819]

Damn things can benchpress a small car hahaha. One day you could get a flat on your way to the field to fly. Break out the ol' jack? NO! Who wants to use those lumbering, heavy, ugly things anyway? Break out your heli and put it under the car. Raise your collective and BAM the tire's now off the ground and ready to be changed! ;)

[bobbybe]

and that's only at 4.8 volts!!!

[MartinS819]

Wow, wrong thread!