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Old Jan 22, 2013, 12:05 PM
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Originally Posted by snrek View Post
nice to get (Or have) the rotor stopped when on the ground.
On a real Gyrocopter, they actually use a clutch assy. to the main drive motor as a "pre-rotator" setup to get the head upto speed before takeoff rollout. In other words, just the opposite. It's exactly like a speedometer cable which spins inside a casing and has (2) rubber contact "wheels" on each end or a gear to spin up the rotor.

Actually, a BETTER fix for you is to cause the servo to tighten an abrasive band around the main shaft itself, thus causing the friction you want much more efficiently. Far side of the band is fixed behind the shaft onto the
mast and other end goes directly to the servo arm.
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Old Jan 24, 2013, 06:51 PM
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Quote:
Originally Posted by XtalHunt View Post

Actually, a BETTER fix for you is to cause the servo to tighten an abrasive band around the main shaft itself, thus causing the friction you want much more efficiently. Far side of the band is fixed behind the shaft onto the
mast and other end goes directly to the servo arm.
Thanks for the idea. Once I get mine flying I may look at changing it to this design. (Still waiting for new batteries)
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Old Feb 07, 2013, 06:47 AM
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New to autogiros

Hi All- I just wanted to thank everyone involved, I'm a member of an RC club in Spain and intend to build a Cierva semi-scale model. I'm just finishing off the J-AG4as an introduction and will attempt to fly it once the wind dies down.
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Old Feb 07, 2013, 09:30 AM
Sky's not the limit, ground is
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Originally Posted by Dan Brown View Post
Hi All- I just wanted to thank everyone involved, I'm a member of an RC club in Spain and intend to build a Cierva semi-scale model. I'm just finishing off the J-AG4as an introduction and will attempt to fly it once the wind dies down.
I haven't read all the posts here but does this model call for blade leading edge weight and negative/positive incidence? I cant see any on the pic.

Don
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Old Feb 07, 2013, 10:35 AM
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The only weight on the leading edge is the CF spar. The blades do have negative pitch, can't recall the exact angle but it's set by the blades' trailing edges being mounted over the LE of their neighbors at the hub. Works fine.
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Old Feb 07, 2013, 10:46 AM
Sky's not the limit, ground is
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Originally Posted by roidspop View Post
The only weight on the leading edge is the CF spar. The blades do have negative pitch, can't recall the exact angle but it's set by the blades' trailing edges being mounted over the LE of their neighbors at the hub. Works fine.
Got it. I was just concerned I didn't see that on the pic of Dan's rotor. Just don't want to see a fail because it was overlooked.
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Old Feb 07, 2013, 11:28 AM
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Rotor head photo

Hi Ron- you're on the ball- I mocked up the rotors as I'm waiting for 2mm carbon rod- the incidence on the plan is made by gluing 10X10mm depron shims of 3mm depron on the trailing edge of the blades. Nice to get a response, I thought I might have joined the party a bit late.
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Old Feb 07, 2013, 12:18 PM
Sky's not the limit, ground is
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Looking good Dan. Great job! Once you fly these you'll be hooked. This is just a gateway gyro. You'll be building bigger and better ones before you know it.
Good luck and welcome to the club.

Don
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Old Feb 07, 2013, 05:37 PM
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Update: I received my new 3s batts. Got all my stuff together and headed out for another test flight. It was a bit breezy on and off so I waited until the breeze spun up the rotor to where I could hear it humming. Gave it a toss and Iím not sure which failed first. The control rod/horn to the rudder or the hinge on the mast. At any rate it resulted in another broken rotor head. I decided my building skills and 4ch abilities just arenít where they need to be to fly an auto gyro, at least not currently. I pieced together a delta wing similar to the one used back in post # 237. I took it out again this morning. It was flying pretty decent but I didnít have enough head tilt from side to side to make it turn without using the rudder. As I was bringing it down for some travel adjustments I landed on a clump of dried tall grass and broke off the landing gear. It still looked air worthy so I made some quick adjustments and gave it another toss. I flew it for another 4 minutes, nice turns and plenty slow enough to allow time to fix my over correcting. I figure Iíll give the AGís another try down the road after I hone my skills a little more. In the mean time I have already made the necessary repairs and canít wait to get in some more stick time.
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Old Sep 09, 2013, 04:25 PM
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Nope, ain't happenin'!

This thing consistently rolls to the right, even inverting.

1) Low headspeed? Most likely.
2) Too much neg. pitch? I am at -4.5 degrees and it's not spinning fast enough.
3) Wrong blade material? I used depron meat trays from the butcher because that's all I could find.
It is roughly 5mm thick.
4) Hyperion 2s/850mA pack and yes it's heavy.

Would like to know who else had right roll issues with a CW spinning head.
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Old Sep 09, 2013, 04:39 PM
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Originally Posted by branded7K View Post
Flight tests were not successful. Tried the 2-bladed rotor and just couldn't get it up to speed.
I'm not the only one so that's a relief. Same here, no real speed!
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Old Sep 09, 2013, 05:47 PM
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Pitch

Hey, anyone with a helicopter pitch gauge (which I used when building this sucker) please stick it on your 2 or 3 rotor blades and reply back what it comes in at? Thanks, I'm suspicious of my -4.5 degrees as part of the problem. Seems -3 degrees would make more sense.
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Old Sep 09, 2013, 05:55 PM
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I've had that wild-rolling thing with mine, but as I recall it was due to ME setting the head up wrong...the LE of the blades was tipped UP instead of down! It made it impossible to fly! The blades absolutely have to have negative pitch with respect to the axis of rotation.

As to rolling tendency on takeoff, it will happen if the rotor hasn't had a chance to come up to speed. The trick is to accelerate at about half-throttle far enough to get the blades up to speed, then add power to climb out. It works like a charm.

Haven't built a two-bladed rotor yet; the three-blade is working so well that I haven't gotten around to it. But Gary's seems to fly great, so.... one of these days.
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Old Sep 09, 2013, 06:31 PM
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Well yeah, that would be positive pitch then! No, we're not that incompetent, Alzheimer's is still a few years away yet. It's -4.5 degree on the L.E. with a C.W. spinning rotor that picks up wind okay, even rolls backwards if it's a good breeze, but it's not spinning amazingly fast either. My next move (after piecing the airframe together again) will be to shift the battery back to the center tower and as you had said.... LONG half-throttle rollout with full-throttle ground break. This means I need a longer strip directly into the wind.

How the hell does Gary hand spin the thing in a warehouse by twisting his body and then just toss it into the air? No way in hell this will do that, I dunno what his trick is besides maybe helium-filled blades!
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Old Sep 09, 2013, 06:41 PM
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The blades MUST be coning at time of liftoff, right? My head and forward speed are nowhere near that.
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