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Old Dec 27, 2011, 10:34 AM
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Joined Jun 2009
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FW SU-35BM (S) 2011.12 Version 1 - Frame only

EDF Units: Standard 70mm EDF with cw and ccw 5 blade rotors.

EDF mount area and duct dia:
Inlet 80mm
EDF Mount 74mm
Aft EDF exit 70mm
TV Nozzle 60mm
CS fan units are slightly longer and will require sanding into position.
Duct does have two choke points at the gear mount and wing spar. In board cheats were likely added likely to compensate

Special Consideration should be given with Frame Only model setup. Trying to maintain CG while adding heavier motors wire servos etc in the tail makes it harder to CG unless going to a larger battery because the battery can't be moved forward of the bulk head which has the nose gear retract mounted.
For build considerations the ESC's are set far forward in a center vent at cg giving a motor wire length of 380mm. This is hard on the motor wires and is above recommended limits especially in power levels are increased.
Stock uses 14awg but draws only 45+ amps. Many 70mm setup with more power go up in amps ~60+amps giving consideration to 12AWG at that length which again increases weight in the tail make cg that much more challenging.

Sample Setups:
V8's Initial sample setup SU-35 AUW 3178g (7 lbs) (e.g. 5000mah lipo, 2x80a esc's, 2200kv 2839 x 2 motors, 10awg wire between esc & battery, 13awg wire from esc to motors)

Motors: 3D 2849-2200kv ~47amps ea. Purple Power (BH)
Stock 2200kv motor: 100g, w/ fan: 175g

Drive train placement:
Battery to motors is ~580mm
Battery to recommended ESC postions ~150mm
ESC to Motors ~ 380mm
ESC is not in the duct air stream but in the center channel with various ventalation driven by the EDF suction.

Battery Bay Dimensions/Weight limit: 200mm L x 58mm W x 75mm H front 65mm H rear

Battery Recommendations: Select this link to Battery List W/ Weights, Amps Outputs & Vid performance footage. Both stock and others will benefit from heavier batteries to compensate for CG.
4000mAh 650g batts have been reported as CG-160mm and had 3min basic flight times.
4600-5000mAh 750g-800g can CG 155mm-145mm but are heavier. They were reported to have 4min flights with vertical and speed passes.
5000mAh+ 800g+ batteries with High C counts have been reported to perform 3D well.

Most pilots in the first few months of release are finding batteries in the 700g to 750g with above 140 amp outputs to be a good all around battery.
Basic batteries like the Turnigy 5000 30C also showed surprising results at the beginning of the flight.
Thus battery choices may vary depending on your flying style; Easy level passes, High Speed passes, Repeating verticals and 3D.

Recommended CG: from wing root on fuse, 145mm - 155mm.
A good reference for 155mm CG position is the LE of the box hole that connects
the aileron radio wire to the wing.

Landing Gear: Standard FW Etracts used on F-18, Euro etc. These match PZ15090 but struts take 4mm shaft rod.
Very nice struts. The provided FW retracts do have play in them.The picture below demonstrated either swaping an PZ15090 Metal Trunnion retract with the Freewing or putting the metal trunnion in the FW Etract.
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Last edited by Maxthrottle; Feb 03, 2012 at 11:47 PM.
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