Sherman

I have always used standard Futaba servos for both my 40 and 60 size planes (the S148 which used to be supplied with the radio, and the 3004, the servo now supplied with the radio). I have had aerobatic planes, such as the Goldberg Chipmonk, the Ace Cloud Dancer, the 60 powered Kaos, and numerous 46 powered planes.such as Tower Kaos). It hasn’t dawned on me that these standard servos would not be strong enough for my planes. Now, I notice the Goldberg Skylark 70 calls for a minimum servo strength of 54oz. And although the Revolver calls for five standard servos, the review in MAN
And advertisements for the Revolver call for a minimum of 50oz. However, the reviewer in the MAN used #3001 servos, which only have 33oz.

First off, how nervous should I be in using 3004 Futaba servos for the Skylark 70 and Revolver (am currently flying the Revolver with the 3004 installed), and if caution or safety dictates, would it be better (cheaper) to use more powerful servos, or to upgrade the receiver battery to 6Volt. If upgrading to 6 Volt, do I use the same 600 mah capacity, or do I need an increased capacity for the same length of performance. I really hate to have to start getting into the higher torque servos if I can avoid it (and I already have received information on getting the maximum mechanical advantage when hooking up the servos). Would appreciate your thoughts and comments on this.

DadsToysBG

My Feedback: (35)

What you use is up to you. Just keep in mind that no plane has never crashed because you used to much servo, but many have gone in because of less. I always use more then what is suggested. For example the JR Sport 126 @ $35. ea is MG at 126oz at 4.8v. Is it to much for 40 size YES will it cause the plane to crash NO. Can you use them again all longer planes YES. Dennis

bigdarylg

i would upgrade to a six volt nimh battery. i,ve started using 2200mah batteries from batteryspace.com. they sell for like 10.95 ea.

colecaz

Here is a website that has a calculator to tell you how much servo torque you need.... Prepare to be surprized...

http://www.csd.net/~cgadd/eflight/calcs_servo.htm

lrb75

My Feedback: (12)

If you had to use anything more than a standard servo (3001, 3004, 148) on a plane the size of the Skylark or the Revolver then 90% of all the 40 and 60 sized sports planes that have ever flown should have crashed. Unless you plan on doing 3d (which neither of these planes can do) or you really overpower the plane fly with what you have. I would seal the control surface gaps to minimize the chance of flutter. One other note the small mid size, mini or micro servos that have alot of torque on their spec sheet should be avoided for these size planes because the gear train isn't as robust as a standard servo.

acarter

I agree with bigdarylg that you should use a 6v battery. If you look at the s3004 specs, it says that if you have a 6v it will give them 57 oz per in torque which is more that you need. Although they are very slow they would work.

Here is a link to the s3004, if you scroll down you can see the specs
http://www3.towerhobbies.com/cgi-bin...&I=LXVW07&P=ML

Good luck,
Austin