First 3D Plane (servo help)
 

Hi all. I am starting to build my first 3D type plane and need advice on servos. The plane is an Extra 330 with a 64" wing span and will be powered with a Saito 100 and using a Futaba radio system. I have a drawer full of standard Futaba S3004 servos, but something tells me these wont do for anything except maybe the throttle. I have a fairly tight budget on this, so I would like to try and go as cheap as possible without compromising things too much. Any help is much appreciated!

RE: First 3D Plane (servo help)
 

I have been told that Hitec 475BB on 6 volts is a pretty good cheap servo. I am planning a .60 size 3D plane build and will be using a mix of Hitec 425BB and 475BB powered by a nimh 1450 @ 6V battery pack. These servos can be found for less than $15.00 each. If you want to step up to a little faster and more power Futaba 3010 and JR 821's are fairly strong and fast but around $30.00 a piece.

RE: First 3D Plane (servo help)
 

The Hitec 475BB is a good servo on 6V but my worry would be the vibration levels that a Saito 100 can produce. The 475 uses Karbonite gears and although they're very strong, they're also very brittle and don't like shock loads or high levels of vibration.

I think on anything with a Saito 100 in it and 3D throws you really should be thinking metal gears, at least for the tail.

Forget the Futaba 3010s if you want any kind of precision. They have *huge* amounts of slop in the output shaft and gear-mesh. I used them on a Saito-100 powered Mojo 3D profile and my ailerons ended up with 3/8" slop either side of neutral -and that's with ball-joints, not just regular clevises.

There are lots of quite affordable mid/hi torque metal-geared servos on the market now and even some of the newer digitals are quite reasonably priced. However, there are also a lot of lemons.

I've reviewed a lot of them and will be publishing my results at RCModelReviews as soon as I've cleared my plate of work (you know, the kind that pays the rent) :-)

RE: First 3D Plane (servo help)
 

Thanks, Blazer1. Is this the servo you are referring to?

http://www3.towerhobbies.com/cgi-bin...?&I=LXDEM1&P=0

RE: First 3D Plane (servo help)
 

Thanks for the heads up XJet.

How about either of these:

Hitec HS-625MG High-Speed (would this have enough torque)

Hitec HS-645MG High-Torque (would this have enough speed )

RE: First 3D Plane (servo help)
 

IMHO You COULD get by with 3004s on everything but the rudder. For KE you will definitely need some more grunt there.

However digitals with better torque are now not expensive and that is what I would reccomend.

Futaba S3152 will do [ I am using these on a 3D profile with a 120 ] or even cheaper are Spectrum. $90 to $120 for 4 ?