Super_Dave

I'm in the process of building this awesome kit and I'd like to know if I need to upgrade my servos before I finish it. This is my biggest plane so far infact all of my aircraft before this one have been 42inch wing span electric F3A pattern flyers. So I'm not sure if I'm going to need some better servos for this plane. I bought the Spektrum DX7 to go with this plane so it came with the DS821 servos which put out 72oz/in of torque. I know thats enough for the ailerons but I'm wondering if that 72oz/in of torque is going to be enough on the elevator and rudder. I'll be doing mostly pattern flying with it so I'm probably going to be a bit hard on these servos. If I need to upgrade I have no problem spending $120 or so on two servos to keep me from crashing.

Flying weight of this plane is about 7.5 pounds. The elevator isn't exactly a 3D sized control surface either.

alan0899

G'day Dave,
The servos that come with the DX7 are fine for a 60 size pattern ship, but you may need 2 for the elevators as well as the ailerons, so you will need 1 more, for the throttle & 1 more for the rudder, that's 6 in all, this is where a good digital for the rudder of about 10 or 11 Kg is worth it.
You will find that pattern flying does not need super throws, & high torque, but accuracy is a must.

Tired Old Man

My Feedback: (1)

The 821's will be just fine. No worries there.

Deadeye

Agreed. I fly mine with Hitec 475's, which aren't rated quite as high in torque.

Super_Dave

Great thanks for all of the information! I figured the high speed would put a lot of stress on the servos gears so I wasn't sure if I needed metal gear servos or not. They are digital so they should be good and accurate.

Deadeye, that is a beautiful Extra! I'm hopping mine will look atleast half as good as that one. How much time did you spend covering it?

Deadeye

Thanks Super Dave! I think I spent about 40 hours on that covering job. I had a friend with a vinyl cutter cut out the Isis and the lettering beneath the canopy. I spent at least another 40 hours planning it all out. It's all Monokote, no vinyl on it, and just a little clear mylar over the canopy decals:

Super_Dave

I'm still trying to decide on a color scheme for mine. I want it to be very eye catching but still fairly scale. I love the Matt Chapman Cap 580 paint scheme but there is no way I'm going to do that on my own with my ultracoat. I started in cars and I enjoyed making paint schemes for the bodies but its so much harder to do it with this coating compaired to paint.

I do know some things that I need to include on mine. With the sailplane I have I covered it with transparent white on top and transparent blue on the bottom of the wing. When the light shines through the white it makes the blue light up and the brighter the sky the easier it is to see. Of course thats not exactly scale but I have to add that into it somewhere.

Oh yeah and deadeye I'm not sure if you have done much low speed aerobatics but if you have how effective is the elevator and rudder? They are a bit smaller than I thought they were going to be. Like I said I will be doing mostly pattern but I'm going to try some minor 3D manuvers with it when I get comfortable too.

Deadeye

I made my rudder and elevator much larger than stock, and counterbalanced them both. I can hover mine pretty easy with the Saito 125, but still have to fool with the CG a bit for true 3D. Of course, I can fly it pattern as well, as I use pull-pull on the rudder, and each elevator half has it's own servo driving them with only about 6" of push rod. Flutter isn't a problem.

Super_Dave

Well I already have the rudder and elevator built so I my as well fly it as it is for now (it will give me an excuse to build a 2nd one later on[8D]). This is my first kit and its so much nicer knowing I can change things to my liking along the way! I am a little worried the stock control surfaces are to small so I might have to scrap them and build my own sense it looks like its so easy to do. I found a thread of someone else building this plane and they made the same modifications you did and I see you posted there too. Can you tell me the dimensions of your elevator and how much you took off of the stab? The size of your elevator is about what I'm looking for.

I still haven't looked at how they want you to set up the servos yet but I like the pull-pull rudder setup on my electric plane and I like your setup for the elevator.

Deadeye

I will take some measurements for you. Give me a day or two.

FlyingPilgrim

My Feedback: (26)

Just replied to same thread in kitbuilding.
Only need to post same thing once[:-]

Super_Dave

Yeah I know but I wasn't exactly sure where to post this one. I figured I would have more people who actually built the kit in the kit building section but no one has replyed.