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Apr 06, 2009, 04:36 PM
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Mud Duck Bill's Avatar
oops http://www.youtube.com/watch?v=haCltu30Ids
Last edited by Mud Duck Bill; Apr 06, 2009 at 05:34 PM.
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Apr 07, 2009, 08:02 AM
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JochenK's Avatar
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Bill,

your prop wash test looked alright.

When you've got your battery, make your gyro ready for flight. Then stick a piece of paper to the side of your gyro and suspend it by the nose wheel. Draw a vertical line down from the point of suspension. Then hang your gyro by the top of the rotor mast and draw another vertical line down from the point of suspension (see here: https://www.rcgroups.com/forums/show...&postcount=53). Where those two lines intersect is the c.g. of your gyro. The hang angle is the angle between the line drawn when you hung your gyro by the top of the rotor mast and the center of the rotor mast.

On my Minimum v2 the hang angle is 8° and the motor thrust line is about 1.4" above the c.g.

Jochen
Apr 07, 2009, 10:18 AM
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Mud Duck Bill's Avatar
YA KNOW old Bill hasn't used a Protractor sense High School but when I went looking for it there it was with my mechanical drawing set. Boy does that bring back memories. Any way back from memory lane this is what I came up with.
Apr 07, 2009, 11:12 AM
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JochenK's Avatar
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Bill,

did you use the new batteries? I not, you'll have to repeat the procedure. And, next time, draw in the centre line of the rotor mast so you'll have the hang angle.

Jochen
Apr 07, 2009, 11:41 AM
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Mud Duck Bill's Avatar
yes this is with the battery I am going to use. I drew in the mast line and if I am at the right axis point it looks like 10 degrees
Apr 07, 2009, 12:36 PM
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JochenK's Avatar
Thread OP
Bill,

10° is good. 2.5" between the c.g. and the motor thrust line seems a bit too much. Can you lower the motor by about 3/4"? And how much does she weigh with the lipo battery?

Jochen
Apr 07, 2009, 02:57 PM
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Mud Duck Bill's Avatar
Well I just came back from the UPS store and it weighs the same with the lipo which is 2 LB.s How large of a prop do you have on your autogyro ? I am using a 6x4 maybe a larger one is in order? I couldn't resist and took it out in the yard in the limited space I have I could see the blades begin to cone and I got off the ground just a tad before I had to stop.

I have to go back to work tonight so It will be a few days before I get to lower the motor and is 3/4" enough or do you want more. Bill

" ONLY BREAK WHAT YOU CAN AFFORD "
Last edited by Mud Duck Bill; Apr 07, 2009 at 03:42 PM.
Apr 07, 2009, 03:12 PM
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JochenK's Avatar
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Bill,

I'm using an APC 9"x4.7" slow fly prop.

Did you really do a short hop? Without flipping over? Maybe you shouldn't change anything. Wish you luck for yout first flight.

Jochen
Apr 07, 2009, 03:44 PM
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Mud Duck Bill's Avatar
It Did Want To Roll To The Left A Little But It Did Come Off The Ground A Few Inches
Apr 13, 2009, 04:02 PM
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Mud Duck Bill's Avatar

Maiden day


Gentlemen : Tomorrow is maiden day for my red neck minimum build and the field is still rough so it looks like a hand launch. Any advise on how I should approach this and any thoughts on what to expect. It probability won't be pretty Wish me luck Bill
Apr 13, 2009, 04:12 PM
Tannenzäpfle-Terminator
Hephaistos's Avatar
Hello Bill..........

I will press my thumbs for you! I cannot give you any hints except from this: Get some bottles of beer before the maiden-flight. As Goethe said, "ERGO BIBAMUS" ("Lets have a drink") is the only conclusion fitting perfectly to every possible assumption:

I crashed my gyro before it took off: ERGO BIBAMUS!
It flew like a bird and did not want to stop: ERGO BIBAMUS!

I don´t care about, but I had some fun: NOW TWO TIMES: ERGO BIBAMUS!

Bye
Mike
Apr 14, 2009, 05:03 AM
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JochenK's Avatar
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Bill,

look here:
https://www.rcgroups.com/forums/show...&postcount=138
And I do wish you luck.

Jochen
Apr 14, 2009, 08:49 AM
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Mud Duck Bill's Avatar
As always excellent information Thank you and here we go. bill
Apr 14, 2009, 02:26 PM
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Mud Duck Bill's Avatar
http://www.youtube.com/watch?v=-V4CP0Fpglg

Well it didn't go so good but that was to be expected I think the wind shifted and I got a bit of a cross wind,also I don't think I leveled the nose before I let go. All things to ponder before the next try If you see anything else let me know Bill
Apr 14, 2009, 06:02 PM
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Boneswamped's Avatar
Great Effort Bill!
It certainly sounded as though your rotors were up to speed in the video. I would agree with you that your release angle on the hand launch didn't look quite optimal(hard to say). It seemed that you were nose high, and slightly rolled to the right upon release. I'm guessing you had a left quartering headwind as well. Being directly into the wind is very important, escpecially with an untrimmed model. As far as your comment about not bringing yourself to let the model go; we all feel that way on the first flight. You built it from scratch, you can certainly REBUILD it, so don't worry. I commend you on your efforts so far, and good luck! I enjoyed your video.
Regards,
-Mike

p.s Bill; because winds are more critical when launching an autogyro than a fixed wing I use a very light piece of silk ribbon tied to my antena so I can do that last minute check just prior to releasing the aircraft.
Last edited by Boneswamped; Apr 14, 2009 at 06:06 PM. Reason: afterthought


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