Analog to Digital Servos

[John Seybold]

Hi,

I'm thinking of trying digital servos in my next build and was looking for some recommendations for servos. I'm using a Futaba transmitter and have used their servos as well as Hitec in the past. With regards to the digital servos what are some model numbers that you guys use for rudder, throttle and mixture control.

Thanks for any suggestions and opinions,

John

 

[Hydro Junkie]

How big of boat? A bigger boat is going to need a more powerful rudder servo

 

[John Seybold]

First project wil be a 90 rigger

 

[Steve Seebold]

I use HiTech 5945 digital servo for the rudder on my gas monos and I just use a cheap analog servo for the throttle.

 

[Hydro Junkie]

Futaba Rudder Servo options:

S9155-153 oz-in @ 4.8v 192 oz-in @ 6v

S9156-272 oz-in @ 4.8v 340 oz-in @ 6v I use this in scale boats at 4.8v with no problems

S9157-425 oz-in @ 6v

All are coreless, ball bearing, metal center cased, metal geared and water protected

As far as throttle/remote needle servos, pretty much any servo would work with around 50 oz-in of torque. If space is an issue, an S3150 slim wing servo might be an option as long as you're using 4.8v. One other note on this servo is that it is presently on backorder.

To see the Futaba digital servo page, the address is:

http://www.futabarc.com/servos/digital.html

I went back and looked up your HS5945 and found this:

Stall Torque (4.8V): 152.75 oz/in. (11kg.cm)
Stall Torque (6.0V): 180.53 oz/in. (13kg.cm)
This means that it's comparable to the 9155 at 4.8 and only slightly lower at 6 volts. For a 90 rigger, a bit more torque might be advisable considering the speeds they can hit. I'd probably look at the S9156 to start with