Servo help on first larger Electric

[ronrandle]

Hi all, I've ordered a 25% Sukhoi listed below and need some servo help. I'm comfortable choosing servos for my smaller 55" 1200 watt planes but want to make a smart choice on this larger plane.

What amount of torque am I looking for for servos in this size of plane?

I believe the elevator uses a joiner so I need to either use one larger servo or do a dual elevator set up and move the servos forward in the plane.

I'm trying to keep this plane light and inexpensive so I'd appreciate any recommendations you have. Digitals are fine but may be out because of cost.

I'm planning on using the following for power:

Hacker A50-16L
Xoar 18-20" propped for 2,000w
CC85HV
Dimension engineering Sport BEC
2-4S4000 25C packs

I'll start a build thread as soon as it arrives.

Thanks for your help.

Ron



http://www.peakmodel.com/index.php?main_page=product_info&cPath=1_99_96&products_id=542

[staggerwing]

I've done several giant elec & feel it mostly depends on type of plane & how you're going to fly it--no matter what the power is. This obviously being a 3D aerobatic bird would I assume require servos no different than what might be reccommended for gas power --- IE comparable if not same forces on moveable control surfaces.
There are currently a ton of servos on todays market--analog & digital--if you've got $, flaunt it, if not, try to find feedback on lesser expensive servos ---after all, it's been proven some big buck RC items come from the same source as do comparable low cost items,w/ just the label & maybe a slight exterior change .

[ronrandle]

Thanks Staggerwing.

You're right, I will primarily be flying 3D with this plane and have no issues with OEM brands that fly under the radar, so all brands are under consideration.

I guess I'm trying to figure our how much torque I need for the bigger planes control surfaces. Will Hitec (or equivalent) 625MG's at 80 oz be enough or do I need 645's that are a little slower but have 100+ oz of torque.

Or is it a combination of both, 625's on ailerons and 645's on elevator and rudder.

Anyway, that's the info I'm trying to get my head around.

Thanks again

Ron

[Goinav8n]

Hi Ron

I used the 5645 digitals in my latest project with a 5 cell reciever pack. These are very good inexpensive servos. Troy Built is a good source. I got mine off ebay for 45.00 a piece but it has been awhile back.

You can always look over on the Flyin Giants web sirte as these guys sell stuff pretty cheap in the swap shop area. I have found most of the servos I have gotten from these guys come exactly as descibed.

Jeff

By the way I am not to far from you

[ronrandle]

Thanks Jeff. I had looked at the 5645's and like the specs.

Ron

[Yardbee]

Hi Ron: Have You Checked Out the TS-150 Digital Servos From Tower Hobbies Priced @ $39.99 I Am Using Them On My 30% Size Yak-54 & So far They Have Performed Flawlessly! According to Tower There Made By Futaba. The Specs Are Pretty Impressive: 162 Ozs of Torque @ 4.8 Volts & 193 Ozs of Torque @ 6.0 Volts. I Am Also Using the Hitec HS5645Mg Servos on My QQ 72" Yak. I Have Had Good Luck With Both Brands & No Issues. Looking Forward to Your Build Thread Of the 26% Sukhoi!! I Have The Exact Model.

Good Luck: Joe :)