RC India

Cant seem to spot the difference between Futaba 3001, 3003 & 3004 servos. Any one?

3001 is less torque and slow compared to the other two.  There seems to be little difference between 3003 and 3004.

S3001 made for helicopter because helicopter has too much vibration so Futaba has made this servo with indirect drive potentiometer and also it has ball bearing, it has less torque but it is more precision. If you read technical specification of helicopter servos then you will notice that all of them have indirect drive potentiometer.

S3003 and S3004 both have similar electronics, bother have direct drive potentiometer so it is not recommended for helicopter use as per futaba. Because in direct drive system vibrations shocks directly travel to potentiometer and become damage easily. S3003 is standard servo without ball bearing and S3004 has ball bearing, in fact you can buy ball bearing upgrade kit for S3003 servo to make it S3004.

That is why you will see S3001 servo is more expensive than S3003 and S3004 but price difference between S3003 and S3004 not so much.

Yeah Anwar thats exactly what i noticed on the Futaba site. But the price difference between 3001 and 3003/3004 is quite substaintial. didnt understand why? And thanks for moving the topic to its correct place, sorry didn't know where to put it!

Thanks very much Rajib for the super explaination. I think now i know these servos a little better.

So if the 3001 can withstand more vibration would they give longer life in a plane? That brings me to my next question "Can the S3001 be used for 60 size scale planes?" Bought a few warbirds at the Amby Valley show, so now i need 30 odd servos!

I have seen the s3004s used in such planes widely.  A .60 size glow engine mounted well should not cause too much vibrations.  The 3001s should work just fine too.

People have been moving both of these from one plane to another, occasionally changing gears in crashes, for years on end.

There are some good cost effective choices from Hitec too.

Thanks once again Anwar. So what do you suggest? I use a Futaba 2.4 Ghz system

Other than the 3001 and 3004 Futaba ones, Hitec's 425BB servos are also widely used for non-3D flying. They all seem to last many years.  Do wait for a little bit to see what others suggest, as there are other brands like Power HD which may serve the purpose at lower prices.

Hello Manav,

At our RCTC field one guy used to fly 50cc gas model with Futaba 3003 servo and result his plane hit inside military zone and crashed. He was flying that plane more than 3 days and later his servos failed, so it is very clear that these servos are capable of taking more load than recommended. But if you believe that human life is more precious than our models then it is not ever recommended using any servos higher than its recommended application. It is always better if your model needs 2.5kg torque servos you use 3 or 3.5kg torque servos, in that case they last very long and because of overload they fail.

There are so many technical things about selecting servos for your model, I have found two very nice website links with lots of details, and I think if you read them you will understand better.

URL: http://www.hooked-on-rc-airplanes.com/rc-servos.html#2
URL: http://www.futaba-rc.com/servos/digitalservos.pdf

A fellow modeller has NIB Hitec HS 485s for sale at a very reasonable price of  :Rs: 800. Good GP servo.

The Hitec ones would be a good investment.  The higher torque certainly is an advantage.

@Rajib: Thanks for the links. Read through them. Already feeling smarter  :thumbsup: ;D

@Anwar: Thanks for the advice. Seriously considering them  :thumbsup:
One queston though, are the Hitec servos absolutely and always compatible with Futaba 2.4Ghz Tx/Rx systems? And yeah, do the Futaba control horns/arms fit Hitec servos? bought a couple of these from Tower: http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXD671

@Sushil: Thanks very much for the info. Very interested in them pending compatibility answer by Anwar. Plz PM details

Thank you all very much for the help  :salute:

These standard servos will work fine with Futaba 2.4Ghz systems, to the best of my understanding.


This is something to be very careful about. Do NOT substitute servo arms !  See these threads :

http://www.rcindia.org/servos-gyros-and-all-electronics/the-importance-of-servo-arms/
http://www.rcindia.org/servos-gyros-and-all-electronics/servo-arms/

@Anwar: Thanks very much for the very useful info. Now looking into the Hitec servos as an option and will always keep the "servo arm" issue in mind  :thumbsup:



@Sushil: Plz PM me servo details or call me at #0-98220-35673.

Once again thank you all for your help  :salute:

[quote author=Rajib link=topic=4947.msg53101#msg53101 date=1300082372

At our RCTC field one guy used to fly 50cc gas model with Futaba 3003 servo and result his plane hit inside military zone and crashed. He was flying that plane more than 3 days and later his servos failed, so it is very clear that these servos are capable of taking more load than recommended.
[/quote]

Cannot imagine anyone flying a 50CC Gas with 3003 servos. Its like trying to drive a Maruti 800 with a DLE-50CC engine.