SR X250 saga
#26
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I couldn't find a 4mm to 8mm prop adaptor for the Graupner props but I did find this solution.
http://www.getfpv.com/graupner-prop-...-4mm-4pcs.html
http://www.getfpv.com/graupner-prop-...-4mm-4pcs.html
#29
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That would be far to conventional for one of my airplanes. But it did give me an idea (that's a bad thing) How about I set it up with a module with a cartridge of helium attached to a deflated balloon actuated by RC. After taxing out to the take off point on the runway I activate the balloon which inflates and lifts the plane into the air. The cartridge capacity is more than the balloon can handle so at about 25 feet the balloon bursts. I activate the motor and fly away. When the balloon bursts it ejects the lifting mechanism so the plane doesn't have to carry it around. (I know, I've been watching to many James Bond movie's)
#30
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Perhaps this is slightly more reasonable, No lack of power for short grass takes but I think the mains will collapse with added friction, but I'll give it a shot. Going from a 40 watt to over 200 watt power set up I won't need much runway.
#32
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Yup these are keepers, great ground clearance but I am having to upgrade the servo. the i300 servo becomes over loaded by any speed higher than walking speed resulting in a spin out. Maybe a ground loop although maybe that only pertains to tail draggers. With the smaller wheels I had reasonable control up to take off speed.
Last edited by zeroback; 06-18-2014 at 08:39 AM.
#33
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Time to wake up my videographer Upgrading the steering servo and getting the slop out of the mechanisms made a marked improvement in controllability, it taxi's sweet now. I received the adaptor sleeves for the Graupner props. The rings seemed kinda loose when installed in the prop but the prop seems to be running vibration free. I think this spinner looks better and it saves a 1/4 oz in the nose.
Last edited by zeroback; 06-18-2014 at 08:31 AM.
#34
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Well I finally had the opportunity to maiden the new X250. Any test that comes back in operable condition is a success although there is some tweaking needed. First taxi and range test went well and the ground handling was excellent considering the 000000 grit sandpaper runway. A WOT burst and it was in the air in 15ft or so Set the throttle to about 65% and trimmed the elevator and aileron. It settled right in. Then I flipped on the gyro and the plane started having spasms which at the time I couldn't identify what was going on so I flipped it off. I left it alone for the second flight. I checked the settings at preflight on batt.3 and discovered I had the rudder backwards and obviously way to much gain. The third take was aborted when the direct drive steering servo failed and it plowed the prop as it made a hard left resulting in some minor wing tip scraps and a need for a new prop. The Kv of this motor is on the light side for this prop. After a few more flights with different props for data purposes, I'll give this motor a proper wind.
Last edited by zeroback; 07-02-2014 at 07:32 AM.
#36
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#37
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The Contender is a great flying plane. Mine is glow powered with a plain FP60. I did the modifications that others have done on here. changed the rudder shape for more area below the thrust line and built it with the upswept wing tips. Really fun airplane.. That's my .02
#38
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The Contender is a great flying plane. Mine is glow powered with a plain FP60. I did the modifications that others have done on here. changed the rudder shape for more area below the thrust line and built it with the upswept wing tips. Really fun airplane.. That's my .02
#41
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I ordered a couple of metal gear servos (quite some time ago) for the steering repair from HK a $12.00 and a $7.50 Turnigy. The $12.00 servo came with spasms in one direction, so HK shipped a new one, no problem . So I went with the Turnigy servo, I must say I'm impressed with the servo it is very smooth, powerful, virtually no backlash and excellent centering. I taxi tested it, with the big wheels, strong steering, a little toe in on the mains and it taxi's great. It's neat to watch it bounce along over rough terrain but still remain on course. Can't wait to get out the triple 0 runway and end my flying drought as well as collect some data foe the motor rewind (winding sorta becomes an addiction once a frame with a dialed in wind is flown.)
Although not much flying geeting done in my spare moments I've been working on this
Although not much flying geeting done in my spare moments I've been working on this