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Old Jan 08, 2012, 04:02 AM
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QLD Australia
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Yes Chris.

Do you add wts to make the crosswise C of G on the highest point of the chord, and put the bolt holes on this position also?

The 4.7mm/5mm thickness of HK blades is apx 30% of the chord, which according to tests reports I've read is supposed to the about the right thickness for that width blade.

But the jury is still out about all this, however Aerobalsa seem to have the eadge over everybody with blade design/performance as yet.

I,am going to try the standard HK blades on a much ighter Benson Style gyro later in the year.
I think they will go well--BUT, I also plan to try a 2 blade rotor.
So I will have to make some more longer blades with a lot of weight in the tips[that this years project]

''Its the crosswise C of G position and the bolt hole position in relation to the blades highest chord point that confuses me at the moment''

Regards, M
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Old Jan 08, 2012, 08:06 PM
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Elizabeth South Australia 5113
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I do not add weight to the L/E of my blades ,but I do use a 6 mm square pine on the L/E which moves the balance point forward. I put my bolts just Behind the C/G ,making the blades nose heavy.
Chris........
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Old Jan 08, 2012, 08:28 PM
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Trailer Down By The River
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thats interesting Chris.. what effect does that have on performance and how far behind the cg do you go?
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Old Jan 09, 2012, 02:39 PM
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Flew again today got the throws better still a lot of vibration I will need to work on that.
Got a good ROG but the wind was just off the runway (my excuse ) and had a couple of tip overs on landing with no damage
I have had a few problems with the hinge on the C30 heads I bought a few for other projects on three of them when assembled hinges have broke just bolting the blades on I would advice you all to check the condition on your heads
Joe
c30 w calder.wmv (3 min 42 sec)
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Old Jan 09, 2012, 03:17 PM
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Trailer Down By The River
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Nice flying! You seem to have dialed in very well. As far as the hinge goes ,mine also broke and I ordered a new head and removed the hinge to use as a template. I use clear polycarbonate which is within a few thousands in thickness as the stock hinge. Although abit stiffer than the stock one it works well and is very durable and I started using it as of last June with no breakage. I got the polycarbonate at my hobby shop and it is made by Midwest products. Others have mentioned using tupperware lids and such too. I always remove the blades after flying and never transport or store it with the blades on .
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Old Jan 09, 2012, 06:31 PM
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Elizabeth South Australia 5113
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G'day Joe
That machine looks as if it handles the wind OK. The funny thing is that I find my smaller models perform better in the wind than the large ones
Turbo
I know you have seen Rich's video for balancing blades ,well I use the same method with the bolt only 1 mm behind the balance C/G.just enough to make the blade L/E heavy. I have always used this method ,and it works fom me OK.
Happy Landings
Chris..........
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Old Mar 08, 2012, 07:33 AM
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One thign I don't understand is this:

On a previous post it shows that "you need to reverse the rotor head".
or it wont create any lift.

I was looking at the 2 photos and realised that doing that doesn't actually
change the angle of the blades.

you can see that the 2 bolts run paralell with the blade and that they
are inline with the center "Spin" point.

when you reverse the rotor head, the 2 bolts are still paralell with the blades
and the 2 bolts are still inline with the spin point which shows that the
BLADES dont actually change angle.
The head does but I cant see where the blades change.
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Old Mar 09, 2012, 03:11 AM
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Quote:
Originally Posted by The_RattleSnake View Post
One thign I don't understand is this:

On a previous post it shows that "you need to reverse the rotor head".
or it wont create any lift.

I was looking at the 2 photos and realised that doing that doesn't actually
change the angle of the blades.

you can see that the 2 bolts run paralell with the blade and that they
are inline with the center "Spin" point.

when you reverse the rotor head, the 2 bolts are still paralell with the blades
and the 2 bolts are still inline with the spin point which shows that the
BLADES dont actually change angle.
The head does but I cant see where the blades change.
--------------------------------------------------------------

Look at the blades endon, and see what happens to the blade angle/pitch when you lift the blade up as it would when it cones up in flight and turning due to 'G' loads.

Better still, if you have a digital model heli pitch measuring meter, attach it on th end and see what happends as you raise the tip of the blade.
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Old Mar 09, 2012, 05:38 AM
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HK Head

Got some spare heads and blades for future projects
Good news the heads were assembled correctly for anti clockwise rotation
Bad news still a problem with the flexi plate out of the packet one of the blade grips was ready to fall off
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Old Mar 09, 2012, 07:03 PM
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Elizabeth South Australia 5113
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Joe
I have a couple of heads in transit from Honkers at the moment for upcoming projects,but I would not bother using the flexing plate. Tupperwear is the way to go...........
Chris..........
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Old Mar 10, 2012, 02:39 AM
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Quote:
Originally Posted by britinoz View Post
Joe
I have a couple of heads in transit from Honkers at the moment for upcoming projects,but I would not bother using the flexing plate. Tupperwear is the way to go...........
Chris..........
Chris totally agree getting some new ones made on my friends cnc router as well as an anti tail strike plate that will limit the down flex on heavy landings
Joe
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Old Mar 12, 2012, 07:25 PM
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Elizabeth South Australia 5113
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Just received a couple of heads in the post.I can understand why some people can find the direction hard to follow,as I got one of each............
The one on the RIGHT is the correct one to use on this model................
Happy Landings
Chris............
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Old Mar 13, 2012, 09:31 AM
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My friend Geoff sent me the CNC cut test pieces for the head today fitted perfect
I need to fit them to a model and get out there and test them
Joe
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Old Mar 13, 2012, 10:17 AM
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Land O' Lakes, FL
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Those wind generators are some big obstacles at your flying field! Wow!
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Old Mar 13, 2012, 10:21 AM
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Quote:
Originally Posted by sailr View Post
Those wind generators are some big obstacles at your flying field! Wow!
A lot further away than they look outside of the flying area no problem
Joe
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