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Old Apr 24, 2013, 12:11 AM
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I've Made some small tweaks to the collective and it's much better.. Thanks Bert

I flown two flights this morning and it's flying really well I will get a couple more in this afternoon.

I'm just tuning the Skookum .. Seems to be good at 60%cyclic gain and 85 % Hiller decay.. But will play more to find the optimum.

Well pleased with it so far
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Old Apr 24, 2013, 11:58 PM
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I've put over two and half hours of flights on the mechs now. Max voltage is 32v average 29v and running at 40 degrees Celsius. I'm amazed at how smooth the 3 blades are and they sound very quiet in flight.

The Skookum needs more tuning as it's tending to balloon into wind and I have to apply forward cyclic.. Just like a flybar. Once I get this sorted it's going in the fuselage.
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Last edited by justy g; Apr 25, 2013 at 12:03 AM.
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Old Apr 25, 2013, 04:20 AM
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The Netherlands
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That is not "flybar-behaviour".... that is "rigid behaviour".
If a flybar is showing this tendency in level flight, the paddles are not properly tweaked to their zero degree position.

Flybarred rotors usually ONLY show this tendency during descend while carrying airspeed, because during descend the paddles get a positive AoA and a advancing/retreating airspeed difference.

The skookum (or any FBL set) should suppress this and if not, you need a bit more "I" gain (or whatever it is called in the Skookum).

It is a very wild guess because I am completely unfamiliar with the Skookum, but just from logic and knowing how a flybarred head works, I think you need to change the Hiller decay a bit as that sounds to me closest to the "I" factor.

You can also use this characteristic: if you use an idle-up with slight forward trim for forward flight, the helicopter will show a very clear tendency to maintain a certain airspeed all on its own, the amount of airspeed being determined by the amount of forward trim. If the helicopter slows down for whatever reason it gets a tendency to drop the nose, if the speed exceeds the "setting" it automatically tends to lift the nose. Takes a little bit getting used to but once you get the hang of it, it is a very useful feature that for example greatly assists in maintaining a certain airspeed during approach.

Brgds, Bert
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Last edited by Brutus1967; Apr 25, 2013 at 04:34 AM.
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Old Apr 25, 2013, 04:47 AM
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Bert

I'm working on the Hiller Decay and Hiller gain settings at the moment. Currently down to 55 %. I have contacted Skookum for the correct advice

With regard to adding trim in idle up... It's the same as pushing a little forward on the cyclic in forward flight. My Vbar flys perfectly well without doing either.. So should the 540

A little tuning is all that is needed...
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Old Apr 25, 2013, 05:59 AM
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I am neither saying that you should tune it out, nor saying that you should keep that characteristic.

I am merely saying that it is very natural behaviour for a multiblade rotor, and that, if so desired, you CAN (not "must") use it to your advantage.

That choice is entirely up to you of course. And if you think it should fly level at all airspeeds, than that is how it should be.

I fly all my multiblades, and at least one two blade without flybar, without any electronic stabilisation (just a simple rate gyro to calm down the tail a bit).

indeed adding trim is equal to pushing a little forward, the difference being, that when you push manually, you don't have a "neutral point" and your flight path tends to go a bit up and down, in other words, it is a bit harder to learn, but it is without a doubt possible. One of my heli's is flying without this trim in Idle up and I need to push it a bit. That is just because that particular tranny can't handle separate trims in idle up and normal. It is not that big a problem.
The other helicopters are fairly big and heavy, and I really can appreciate that in idle up the helicopter has a tendency to keep a constant airspeed, because the bigger you go, the more important a constant airspeed becomes.
Loosing too much speed during descend can really lead to nasty surprises on bigger and heavier scale helicopters.
And no matter how well your FBL set is adjusted, it will never actively maintain an airspeed for you. This slight "misadjustment" will, if handled properly.

That's all I am saying

Brgds, Bert
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Old Apr 25, 2013, 07:03 AM
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Bert

Certainly don't disagree with you as this is pretty standard method I have used In the past.

If it is a characteristic that I have add a little forward trim than so be be it. I just want to tune the 540 as best I can in order to avoid doing this. My vbar will hold it's attitude in fast forward flight
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Old Apr 25, 2013, 07:26 AM
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All I am trying to say is: if you have to keep pushing cyclic a bit, then instead add a bit of trim, and use it to your advantage, instead of fighting it and letting it spoil the fun.

Brgds, Bert
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Old Apr 25, 2013, 07:30 AM
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I Hear you Bert
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Old May 08, 2013, 12:02 AM
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Clearance issues

Ok

I have run into a small problem. Unfortunately the mechs' don't fit well into this fuselage because of the elevator and cyclic servo set up of HK600(original 600e).

With the mechs centralised in the fuselage/doghouse, the vertical pushrods from the aileron levers to the swash plate are fouled by the canopy/fuselage join. Also the elevator ball link fouls the rear bulkhead. The amount of material that would have be removed my compromise the structural integrity in that area and would certainly lead to cracks.

I've decided it's much better by upgrading to the ESP elevator control arm set and aileron levers which will get around this problem..parts are on order.

All part of the challenge of building a scale
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Old May 08, 2013, 07:17 AM
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Quote:
All part of the challenge of building a scale
Been there some times
Convinced thet you sort it out!!

Cheers
Jack
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Old May 08, 2013, 08:41 AM
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Atlanta, GA
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889 Posts
Not sure how bad your clearance issues are but I've used a Dremel to grind away enough clearance on some of my scale helicopters. Minor adjustments only.
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Old Nov 04, 2013, 06:42 AM
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Ok it's time to finish this build..been busy with life, family etc.

I've fitted a wooden base for the rear mechanics and a wooden block for the front. The height is 14mm rear and 10 mm front. Bolted and glue in place.
And then used the round wooden mounts supplied with the kit
Mechs all installed

Lighting kit installed.. Just need to tidy up the wires.

And working nicely
https://www.youtube.com/edit?o=U&fea...id=roWfOXKK3ME


Tail gearbox fairing all cut out and ready to fit
Tail gearbox fitted
Tail gearbox fairing fitted
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Last edited by justy g; Nov 11, 2013 at 11:51 PM. Reason: Additional photo's
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Old Nov 06, 2013, 07:16 AM
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Nearly finished

For those who are interested.. Nearly there hope to maiden within the week
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Last edited by justy g; Nov 07, 2013 at 06:41 PM.
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Old Nov 06, 2013, 03:35 PM
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Australia, VIC
Joined May 2013
362 Posts
Looking great Justy,...thanks for keeping us updated. I love this fuse and can't wait to get my 450 & 600 to wrap my Beam's in.

EDIT~~ Just noticed after a second look... are you going to include any type of foot grip on the top steps near the doors? It looks like you've done the ground rails but none on the steps.

Good luck with the maiden.

Cheers
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Old Nov 06, 2013, 03:49 PM
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Thanks Scanner.. Yes I will apply walkway tape to the upper skids and I need to fit the aerials and the landing light, etc..
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