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a Wing and a prayer

Old 05-26-2007, 06:06 PM
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Major Danger
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Default a Wing and a prayer

Dear Sal,
Now I'm getting beyond discouraged and slipping into irritated. I built a Zagi 48" wing some time ago. A beside that I built a Superfly.
The Zagi is the source of my frustration today because it's been on the shelf for the most part.

First time I took it out with the stock set up 400 garbage motor and 8 cell nimh battery that weighed a ton and a futaba Rx. It flew fine for 50 yards then went berzerk as if it had a brain seizure and flopped harmlessly to the ground. Problem was the Rx connections were loose and everytime I'd put things back in their place and try a flight it would happen again. So I got another one. Same thing. So I wised up and did a little hot glue. I wanted to fly not wait for parts. So that worked I think. But the thing would break 25-35mph range. So basically I'm flying a rock right.

Put it on the shelf and ordered up a mega 16/15/4 and a Castle creations pheonix 35 along with a 3s lipo. Took two weeks to get it all. Got it and got er running. She screamed rather nicely. Too it to the feild I named after myself. Danger Field. Anyway............ It was windy (20-25) and all I had planned was range test and glide test. It went better than I expected. She wanted to fly so I gave her 40% throttle and took her once around and landed her. It was difficult in the wind considering I hadn't had the chance to adjust trims.

Windy windy windy. Two weeks of wind. This morning I had had it. I took her out after being told wings love wind. No one told me they don't love turbulance. The problem I experienced though was odd. I do not think the servos are up to the task of anything besides dead calm. I'm running HS51'sMG I think. Without being plugged into anything you can manipulate these buggers with your index finger and feel the resistance from the gears of course. In the Superfly I'm running BMS bluebird 350's and you cannot move those thing at all if there unplugged. Only with the radio will they budge.

The HS 50-89MG all have the same torque when plugged in 48oz. The BMS blue bird 350mg and 350max mg run 60oz of torque. I've very confused here.

The Zagi seemed to have a mind of it's own today. I can't get the plane past 70% throttle now or the femanine mind takes over and doesn't obey regular command imputs. I darn well know it's the servos. I'm replacing the Futaba Rx for sure. I shouldn't have to use hot glue. It's back on the shelf awaiting repairs because she got a mind of her own and attacked a pack of nearby earthmovers. But thats not going to happen till I replace again the Rx and the servos. But what I would like to know is thus:

1. Why does the BMS servos appear strong as an OX without being plugged in and the HS series pale in comparison. This is nuts.

2. PLease suggest a suitable replacement for the servos.

Major Danger
Old 06-14-2007, 02:08 PM
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salnsp
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Default RE: a Wing and a prayer

The Bluebirds may be higher torque or the gears train simply do not move as well and consequently feel stronger.
The HS-55 servos that you are using (I hope this is correct) do not have enough torque for the electric Zagi. I would use HS-81 MG's or HS-85 MG's. Make sure they are in solid and have no movement. The linkages must be tight and slop free. This should then work for you even at very high speeds. I can't tell you about the receiver except that you should be doing a range check with the power off and then again with the power on. If you get range according to the manufactureres spec then you should be alright.
Old 06-19-2007, 06:50 PM
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Default RE: a Wing and a prayer

Thanks Sal,
You are correct and I was dislexic. I do have the HS 85MG in the plane. Where I came up with HS51 is beyond me. Call it a brain fart if you will. I did many range check on the Futaba Rx with more than competant and experienced flyers. Passed on the ground tests. In the air the connections just seemed to get loose and all hell would break loose. Since this post I have replaced the RX with the CC berg Rx and those connect real tight and snug. No problems at all so far. I've replaced the HS servos because mostly after a hard landing sometimes the servos won't return to zero (to easy to manipulate) and I wind up taking it home to recalibrate. That gets old. The Bluebird 350mg's are now in the plane and wow what a difference in flight. Between the New Rx and servos I had a ball. That is until the mega I bought through your company in May started grinding. So once again she's on the shelf while mega sends a new one. I'm not discouraged now. Sometimes you just have to laugh.

Thanks again

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