How much servo torque?

[runzwithsizorz]

Was wondering aprox. how much servo torque would be needed to throw around a 5" or 6" rudder? Not sure Steve has anything beefy enough.
Also, isn't there a member here that can machine a coupler? Need to hook up a 5mm motor shaft to a 1/4in. flex. Was thinking of just drilling
out an OSE straight 5mm x .150. Also thinking I'd be screwing up the balance.

[LarrysDrifter]

A lot use a Hitec 645mg. Ive used them, but both have locked up...probably from getting wet. I always sprayed them with Corrsion X before use, but I dont think it water proofs. Ive since stepped up to the Hitec 7995 I think its called. 300oz. at 6volts. I also now use a life 6.6v reciever pack. You dont have to go to such a high torque rating as that though. I usually use a 200oz. torque rating for a minimum.

[runzwithsizorz]

Thankz, where do YOU buy your servos?

[egneg]

here are a couple of places I have used.

http://searchrc.horizonhobby.com/index.jsp?N=5527&sid=1338E56796E6

http://www3.towerhobbies.com/cgi-bin/wti0002p?M=HRC

[Fluid]

We should know the weight and speed of the model first to give a recommendation. But the Hitec 645 is probably the most common steering servo used by gas racers, racing boats weighing 13-17 pounds. The 645 has 133 oz-in of torque on 6 volts, but I prefer the 5645 as it has a much stronger centering force - and 26% more torque. If you have plenty of room in the boat the 755HB is a great servo with loads of power and pretty cheap. I have had trouble with cheap servos, if you need reliability Futaba or Hitec are at the top. There may be other good ones but I don't know them.

If you need steering power, be sure to run 6.0 volts with a 5-cell receiver pack, or set the BEC to 6 volts. Otherwise you are giving up 18% of the servo's power.

I have never had a 645 give up on me, but no servo likes getting wet. Spraying with CorrosionX is not enough, the servo lead hole needs to be sealed along with the output arm. Vaseline packed aroung the output gear works.

The best place I've found: http://www.servocity.com/html/hitec_servos.html

.

[Darin Jordan]

If you are looking for high-torque, metal gears, and also the extra precision of a Digital, Spektrum makes a couple of fantastic Digital servos that I've used extensively and just love.

For the high-torque model, the S6030 is a high-torque, 278oz/in Digital with metal gears. http://www.spektrumrc.com/Products/Default.aspx?ProdID=SPMSS6030

I used this in my 44" Delta Force Sniper G1 Gas Mono without any issues... I just love how the digitals return to center. Makes for a much more precise driving feel.

[sailr]

Not a bad price for that servo considering it's digital and the torque it puts out!


If you are looking for high-torque, metal gears, and also the extra precision of a Digital, Spektrum makes a couple of fantastic Digital servos that I've used extensively and just love.

For the high-torque model, the S6030 is a high-torque, 278oz/in Digital with metal gears. http://www.spektrumrc.com/Products/Default.aspx?ProdID=SPMSS6030

I used this in my 44" Delta Force Sniper G1 Gas Mono without any issues... I just love how the digitals return to center. Makes for a much more precise driving feel.

[BrianW]

I have been using this on all my builds. http://www.rocketcityracing.com/HYPERION-ATLAS-DS-20-UMD-FULLY-PROGRAMMABLE-DIGITAL-SERVO_p_1539.html

Digital,Metal Gear, Ball Bearing, 326oz/in @6V $38.95

[LarrysDrifter]

All my servos so far have been bought the the LHS. I bought a couple here from the swap used, but they were junk. Im only buying new from now on.

[detox]

Check out this new high voltage, digital, high torgue, waterproof servo from Hitec. This servo is rated to use safely with higher voltage 7.4v lipo packs or anyother lesser voltage packs. I like the A123 (LiFePO4) receiver packs 6.6v.
http://www.hitecrcd.com/products/digital/waterproof-servos/index.html
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXBJCE&P=7

[detox]

Does anyone know the advantages of coreless servos or HobbyKings new Mi (Magnetic induction) servos?
http://www.hobbyking.com/hobbyking/store/__14832__Mi_Digital_High_Torque_Metal_Gear_Servo_J R_Hitec_11_8kg_0_07_61g.html

[Make-a-Wake]

The Traxxas 2075 is waterproof and has around 130oz. at 6v............................good servo

[sigelitest]

http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=10746

[runzwithsizorz]

Thank you all so much for your responses. think I'll go with Darin's spektrum suggestion, for I have long put off upgrading my old DX3s tx to a marine. Might save some money on shipping for both the conversion, and the servo.
Perhaps I should start a build thread, for I have so many questions to ask. I am trying to build a bullet proof Titan 33. BTW, I do have a receiver pack.

[LarrysDrifter]

You should start a build thread. We enjoy reading them and you will learn some things in the process.