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Old Sep 09, 2013, 06:49 PM
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In his videos, it appears that is one long warehouse. I know mine could get off and flying easily in that amount of space...whether I could turn tight enough keep it in one piece afterwards is debatable. With mine, outdoors, no wind, I just flip the rotor to get it started, power up, roll maybe 80' or so and off it goes. As to how Gary does it, I'll bet he'd tell you if you asked.
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Old Sep 10, 2013, 04:07 AM
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Hi Dude, I had quite a few issues with my Monotwirl at first (all my own stupid fault) which is quite similar to this model.

I also had a violent roll to the right ending in an inverted crash, BUT, the Monotwirl turns CCW. The first problems were caused by the hang angle being too low, i.e. the C of G was too far back compounded by having a faulty (and too weak) aileron servo. Have you hung yours on a piece of string suspended by the head to see how she hangs? Is you aileron servo ‘up to it’?

I messed around quite a bit with different blade sizes and carbon rod, tube and spruce LE’s but the real sweet spot was when I built the head and blades EXACTLY as described on the plan, maybe your 5 MM meat tray foam is twisting under load??

I would try a hand launch first, you can feel if the model is pulling upwards and or to the side and although with Depron blades it is not as pronounced as with wooden blades they will whistle slightly when up to speed. A tip here is not to run but keep walking fast, they do take time to spin up.

I will measure my Monotwirl blade’s angle when I get home with my Hely pitch gauge (or I may use the ‘Spirit Level App’ which I put on my new smart phone yesterday ) and let you know.

One thing that I learnt playing about with Depron blades was that the amount of flex along the length of the blades seems to be quite critical. Depron does not have much mass to counter act conning and I think that getting the correct compromise of stiffness/ ability to flap is pretty important.

Good thing is that a couple of strips of Depron and 15 minutes gluing are all you need to knock up a new head when you trash one. Keep going, I did with my Monotwirl and she now flies really sweetly and has pretty much been my favourite ‘end of summer’s day, sun going down, no wind last flight’ model this season.

Good Luck,

Paul

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Old Sep 10, 2013, 10:43 AM
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Just measured my Monotwirl, - 10 degrees which is spot on what it is supposed to be for that model. I would suspect that yours should be around the same as they are both flat plate foam profiles.
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Old Sep 10, 2013, 12:54 PM
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Okay, you've answered most of what I wanted: 80 feet is PRETTY DAMNED LONG! For something under half a pound, it sure is! This launch technique is what I need this thing to be able to do because I'm disabled:

Autogyro Fun Indoors (1 min 38 sec)


Can you "pump" the head up in your hand like he does and toss it effortlessly in the air? Well, that's what I want mine to do and if you can't do it then yours is really not equivalent to his setup either. So I gotta go back to him but he's not big on sharing details. I see a LOT of "high fiving" in the thread and whatever but very little detailed info, like blade pitch for example. Or setting the blades to 120 degrees apart as easily as possible, stuff like that.

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Originally Posted by roidspop View Post
In his videos, it appears that is one long warehouse. I know mine could get off and flying easily in that amount of space...whether I could turn tight enough keep it in one piece afterwards is debatable. With mine, outdoors, no wind, I just flip the rotor to get it started, power up, roll maybe 80' or so and off it goes. As to how Gary does it, I'll bet he'd tell you if you asked.
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Old Sep 10, 2013, 01:04 PM
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Paul: I know my 5gram servo is too weak but that does not affect spin up nor getting it off the ground. I don't have anything larger here. I just wish to see the POS fly, even if it's just a minute, THEN I'll blow time and effort on it. I may try a new head using Dollar Tree foam as the poster above you claims he uses anyway. I see no reason to need Depron meat trays, plus the foamboard stripped of the paper will be ~3mm, losing 2mm of 'drag' right there! That should add some headspeed, matter of fact I should do that now! My L.E. consists of the small wooden skewers from Walmart, not CF rod. I only acquired CF after head was completed. I intend to stick with skewers, as entire head has survived 5 crashes, 2 on concrete. "Maybe your 5 MM meat tray foam is twisting under load??" No, the damned thing needs to actually SPIN like it has a purpose in life first! "A tip here is not to run but keep walking fast, they do take time to spin up." I am not physically able to walk fast, due to crashing a real one 9 years ago. It needs to act much like Gary's does, that's the reason why I thought it was a feasible build. That and I got bored with the UFO disks.
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Old Sep 10, 2013, 01:27 PM
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WHAT is negative 10 degrees, rotor blade pitch? There is NO actual pitch setting called out for this J-AG3 build, or hasn't anyone noticed? What's the AUW on yours?

Quote:
Originally Posted by PaulB View Post
Just measured my Monotwirl, - 10 degrees which is spot on what it is supposed to be for that model. I would suspect that yours should be around the same as they are both flat plate foam profiles.
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Old Sep 10, 2013, 01:54 PM
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XtalHunt,

To ROG my AG3, I put it on the floor, spin the rotor by hand, and apply full throttle immediately to get it off the ground. It'll be up in ten or 15 feet indoors with no wind. Once airborne, I must come back on the throttle. The pitch on the blades is established by shimming the trailing edge up about the thickness of the blade material. I think I saw 5mm material mentioned earlier. That may be too thick (draggy) to spin-up well. I'm using 3mm. Hope this all helps.

Gary
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Old Sep 10, 2013, 02:05 PM
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That's what I'm thinking also, that the thickness of these yellow sheets is increasing the neg. pitch too much. Your takeoff roll: Exactly the opposite of how "roidspop" states he does his!

Go figure!

With initial full throttle, I do not notice you're having too much trouble with ground looping and mine has enjoyed doing the Salsa several times now. So jump on full throttle and you avoid ground looping?

I hate tail-draggers, always have. I'll redo the head, hopefully getting this thing to hand launch status. With my legs, I really need it to be capable of hand launching.
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Old Sep 10, 2013, 02:11 PM
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My main reason for jumping on the throttle is to get that rotor spinning. It also prevents the Mambo. Mine is horrible on the ground except at crawling speed.
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Old Sep 10, 2013, 02:21 PM
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Yeah, that's a tail dragger! I took lessons in a Cessna Citabria 25 years ago, horrible ground handling. Why would models be any different?

HOW does it spin up enough by twisting your body like that in the video? Just doesn't seem possible because we're talking 2 seconds between doing that and the hand launch!

HUH?
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Old Sep 10, 2013, 02:24 PM
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I'm forcing air up through the rotor, so it has to spin. Gotta do this when there is no wind to spin it up.
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Old Sep 10, 2013, 02:24 PM
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Okay, I just tried doing that little "body twist" dance move of yours: SQUAT! Moved ~20 degrees!

My head is not right! No, not that head.... the rotorhead. Roughly how much hot glue is in your hub "sandwich" and is it filled with glue? Does your neg. pitch look like ~3 degrees? The hub disks are ~1/16" standard ply?
Plus you basically have a bushing in there? A CF tube, which in turn rides on the CF mast?
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Old Sep 10, 2013, 02:31 PM
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Next one, I'm using ball bearings left over from my Blade CP, that will eliminate any binding suspicions, I guess this also needs to be much lighter than this one. It's pretty sturdy and maybe over-built for the application.
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Old Sep 10, 2013, 02:33 PM
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My rotor hub is probably "filled" with hotglue. I can't remember. It's been too long ago that I made it. 3 degrees might be a good guess. If I was any good at math, I could figure it exactly. I'm thinking 1/32 ply, but it's been too long ago.
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Old Sep 10, 2013, 02:43 PM
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Got a $1 protractor by chance? Your entire 3 blade rotor, is it "incredibly light" in weight? Like 5grams maybe?
If so, then that's my problem.
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