Here's my situation, I'm going to be ordering the Hangar 9 Twist .40 along with the Spektrum DX7 aircraft version. The DX7 is going to come with four servos. Here are the specs:
DS821 Sport Digital Servos
Torque: 72 oz/in @ 4.8v, 88 oz/in @ 6.0v
Speed: .19 sec/60deg @ 4.8v, .15 sec/60 deg @ 6.0v
Size: 1.50 x .94 x 1.47 in
Weight: 1.5 oz
Ball-Bearing: Single
Motor: Cored

I know these would work for the Twist, but I want to save them for my next model I'm planning on getting, and according to the manual these are overkill for the Twist. The Twist recommends [link=http://www.horizonhobby.com/Products/Default.aspx?ProdID=JRPS537]JRPS537 [/link] or equivalent servo's. The specs on these servo's are:
* Size Category:Standard
* Type:Analog
* Torque:40 oz/in @ 4.8V, 49 oz/in @ 6V
* Speed:.25 sec/60° @ 4.8V, .19 sec/60° @ 6V
* Dimensions (WxLxH):.73" x 1.52" x 1.32"
* Weight:1.58 oz
* Bushing Or Bearing:Bearing
* Bearing:Single
* Motor Type:3-Pole Ferrite
* Gear Type:Nylon
So my question is would something like this work as an equivalent?
[link=http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXDEL7&P=0]Hitec HS-322HD Servo Deluxe Karbonite Gear Std U [/link]
Speed: 0.19 sec/60° at 4.8V
Speed: 0.15 sec/60° at 6.0V
Torque: 42.00 oz-in at 4.8V
Torque: 51.00 oz-in at 6.0V
Length: 1.60" (41mm)
Width: 0.80" (20mm)
Height: 1.40" (37mm)
Weight: 1.5oz (43g)

The only big difference that I saw was that the JR servo had 1 ball bearing where as the Hitec in a non-ball bearing servo. Whats the difference in a standard servo vs standard ball bearing servo, besides the obvious? And if it does make a big difference to where I should get a ball bearing servo would the [link=http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXDEL9&P=0]Hitec HS-325HB Servo Standard Karbonite Gear BB U[/link] or [link=http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXVW07&P=0]Futaba S3004 Standard Ball Bearing Servo[/link] suffice? I know this may seem pretty obvious to most of you but Im not to educated on servo's and since the Twist is a 3D capable plane I wanted to make sure I had something ideal for the situation. And if you are wondering, I plan on saving the Spektrum servo's for the Aeroworks .46-.60 Edge 540. Thanks for the help.

You can almost always substitute another servo in the same or greater range of output torque safely.

The 332HD's will work just fine.

Ball Bearing servos will last longer versus Bushing based servos so they are preferable.

But the choice is yours...

Remember that there is some very good likelyhood that even a bushing servo will outlast the plane.

In your shoes I'd opt for the cheaper servos in the 3D plane, knowing that sooner or later I AM going to crash it, since I'll be flying it low and close in.


A .60 ( or larger ) Edge may hold up longer if only because you may fly it out further and higher, giving you more time to land and react... so I'd put the better servos in that plane.

I use mainly Hitec 425BB's in all my 40 to 120 size planes (mainly sport fliers) on all the control surfaces. I use 322's, 325BB's and 422's on the throttles. I have never had a problem with any of these servos. If you want a little more punch, then the Hitec 475BB's (61 oz/in) are only 16.99 and will do for many planes to come.

Curt

I've flown the snot out of a Twist 60 using Futaba 3004 servo's. Never had a bit of problem out of it.

Hogflyer

Futaba S3004, JR ST-47BB, Hitec HS-425, just about any decent standard servo will fly the plane fine.

There are not many 40 size model aircraft that require anything more than a basic, standard size servo. I originally bought Airtronics and have collected quite a few Airtronics servos, their basic servo that comes with most of their transmitters. I've used them over and over again in different aircraft with not a problem at all.

In fact, I had basic servos in my Tiger 60 and encountered a problem with the elevator fading out during some maneuvers. This turned out not to be the servo, but the linkage flexing under pressure. I fixed that and flew that plane and flew it and flew it. It is now about, oh, 6 or 7 years old and still flys with the original servos installed.

Choose what you feel good about.. ball bearing or bushing, standard (more than adequate) or high-torque (a tad bit overbored) whatever. But, the advice given above by opjose regarding the real possibility of limited life for this aircraft, you may choose standard servos.

If you want fast response, most of these servos will work just fine with 6 volt battery packs. You will get more torque and faster response, but shorter battery life (so use a higher capacity battery pack).

Just a thought.

CGr.

Standard servos will just fine. Been flying mine for over 2 yrs on JR ST47's with no problems & still tight using 6V Bty.

Yes the Hitec HS322 or Futaba S3004 will work just fine.
I like the HS425 a bit better than the HS322
http://www3.towerhobbies.com/cgi-bin...&I=LXN586&P=ML