gregoryshock

I've been trying to build Great Planes Waco Classic Almost Ready-to-Fly Glow/Gas Biplane and I'm confused about the servo selection. They recommend Futaba S9001 servos for all the control surfaces. I try to budget my money when I start project, and these servos are pricey. I was originally under the impression that this plane flew with 7 standard servos. It appears that my idea of what standard servo is, wasn't entirely right. I won't be putting in the S9001 because by the time it becomes available it will be too late for me to fly that plane this year. Do any of you know why they recommended the S9001 over the standard S3004? Would the S3004 work on this model? I mean they are using a separate servo per aileron! I don't want this to turn into a big servo debate. I'm looking for a good answer for why they chose that particular servo over a normal standard servo.

Bax

My Feedback: (11)

Those servos were chosen because they are coreless, ball-bearing servos that are a good compromise between speed, power, and price.

gregoryshock

I can't use those servos because they are not available. I want to be able to fly the plane this year! They will not be available until it is too late. Is it necessary for the servos to be coreless? What is a good alternative? What would happen if I used the S3004s for this year?

A. J. Clark

Don't know why they choose that servo . I would consider the s3010. I have been using them in a rascal 110 with no problems.

gregoryshock

Is this the plane your talking about? TowerHobbies.com SIG Rascal 110 Sport GP/EP ARF White/Blue 110"

DGrant

My Feedback: (4)

If I'm not mistaken, Great Planes, Futaba, OS, Hobbico, etc... are all products that have some sort of affiliation to eachother... at least within the distributors realm. Most of Great Planes kits/plans I've seen all have an OS engine depicted on the plans, and recommend Futaba as well. You will never see a Great Planes product that recommends JR or Spektrum, as those are completely different entities/companies/distributorships..... Just as Tower Hobbies, and Horizon Hobbies are completely different in that same fashion.. with each being a head company.. and each has their proprietary brands. Great Planes just happens to use Futaba as such a proprietary brand, just like they use OS from what I know... At least thats what I've seen in the many years I've been in the hobby. I'm sure there's alot to it, but at least you might get an idea about it.

So... with that said... Just read the specs on the 9001's, and find an equally strong (or stronger if you can) servo that suits your budget. Hitec's are a good choice, and most times affordable, especially the analog servos.

You definitely want something stronger then a 3004 in there though. That's a decently large bipe. I might suggest Hitec 645's, or 5645 digitals. The 645's are about $29 usually. Use these on the control surfaces. For the throttle, you can easily use a 3004..(for the choke also if you have it servo operated).

Other then the Hitec's there's still several servos on the market that are stronger the 3004's... without breaking the bank... just don't compromise and settle for standard servos. You're plane is worthy of good strong servos.

A. J. Clark

Yes that's the plane. Only I have the older version. I think there has been some revisions in last few years . The futaba s3010 was one of the servos recommended in the manual.

I agree with the last poster . I wouldn't use the s3004 in the size of plane you have.

j.duncker

My Feedback: (2)

If flown in a scale like manner 3004s will be just fine. Even if hooned about 3004s on the ailerons will be just fine. The 3004 on elevator might be a little slow to respond on full power dive. If you plan to fly knife edge manouvres then you will a rudder servo with CONSIDERABLY more grunt than a 3004.

Here is a pic of my 1/4 scale Stampe which had an OS 120 4 stroke and flew just fine on 3004s with only 2 on ailerons, the top ailerons being connected to the bottom wing by pushrods. It is being sidslipped in to land with rudder and ailerons cross controlled and some throttle, it was a pretty draggy configuration. Loved flying that thing. There was enough rudder authority for good 4 point rolls.

RBACONS

My Feedback: (3)

Agree with J. Duncker. 3004s on the ailerons will be fine. Rudder and elevator could stand more torque if you're pulling out of a high speed dive or doing knife edge.

Desertlakesflying

My Feedback: (28)

If you are overly worried just go with these... I have them in my T-One sport jet. 2.2M Or the little brother the LF-13 at the same place

PowerHD LF-20MG Metal Gear Digital High Torque Servo | Value Hobby

gregoryshock

I have a hog bipe by sig. It used only 1 standard servo for all 4 ailerons. It flew on a .61 size engine.

I think so too. I can't remember ever doing a high speed dive.

Your link is messed up. I had to copy the link to a text editor to see what is wrong. I think what you want it to do is this: PowerHD LF-20MG Metal Gear Digital High Torque Servo Value Hobby Thank you for the suggestion but I think for now I should stick with a vendor I trust. And wow the price is cheap!