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Old Jan 30, 2013, 02:01 PM
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Thank for the above information, it surely will come in handle, very soon.
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Old Jan 30, 2013, 02:06 PM
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Thank for the above information, it surely will come in handle very soon.
i added the pic just now.

but remember, i think weve all had problems with ducts bending to meet the props and being obliterated. As we tighten the duct diameter, expect those occasions to worsen

the Embry riddel team was given many hours on Boeings 3D polycarbonate printer, which was why there ducts were so ridgid. i dont know how we will do the same...
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Old Jan 31, 2013, 07:50 AM
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Not very much tip clearance! I will have to file down the tips of these props a very small amount hopefully maintaining 1/16" distant mentioned above. I opted not to use the salad bowls, after removing the base, they just did not have the structural strength I had hoped for however, I may still use the upper ring because of the radius. Instead, I opted for the cut down 12" concrete forums.
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Old Jan 31, 2013, 01:21 PM
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i have considered the same use of the forms... but how are they on wheight? my styrofoam are just too flimsy...

And how stiff is your 120 degree supports making the duct? will it survive minor bumps without bending into the prop?

do you reccomend turning the whole arm with motor? or using a hinge on the motor w servo? (for bicopter use i mean)
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Old Jan 31, 2013, 01:42 PM
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i have considered the same use of the forms... but how are they on wheight? my styrofoam are just too flimsy...

And how stiff is your 120 degree supports making the duct? will it survive minor bumps without bending into the prop?

do you reccomend turning the whole arm with motor? or using a hinge on the motor w servo? (for bicopter use i mean)
I am rotating the entire assembly, arms and Ducts as one unit. See the video posted here

As for the structural strength of the duct, all I can tell you is, MUCH better than foam. As for weight, I don't worry about weight until after it is flying (of course I make sure there is enough power), then I will go back over it looking for areas where I can reduce weight and make things more efficient.
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Old Jan 31, 2013, 02:08 PM
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I am rotating the entire assembly, arms and Ducts as one unit....
im doing the same, the ball links didnt seem to work well.
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Old Jan 31, 2013, 04:02 PM
Lets make it remote control!!!
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nice looking ducts...lookin good .......good luck fellas
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Old Jan 31, 2013, 04:15 PM
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nice looking ducts...lookin good .......good luck fellas
Thank you, here is a preview of what's to come. The Radius (made from a salad bowl) just sitting there drying, it is freshly painted.
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Old Jan 31, 2013, 04:35 PM
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I may leave that Radius off, I am undecided.
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Old Jan 31, 2013, 05:14 PM
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looks good Rev. keep up the good work..

Terry
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Old Feb 02, 2013, 12:04 AM
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i have bought a 10.375 ID x 48 long, cardboard cement tube, i plan to have 0.185 inch clearance for my 10" Dia MA tri-props...

This looks cheaper and easier than carbon fiber... and at 10.375 x 1.2 inches i can make many ducts quickly...

( on my table saw, i should get 35-ish ducts off a single 48 inch long tube )
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Old Feb 02, 2013, 02:59 AM
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The Very first test of the new Weight Shifting/Transferring System.

http://youtu.be/iQ_N94XRM1Y

I have yet to place an order for the servo saver but I figured I could get some bench and hovering testing done.
subscribed. Clever application .. shifting weight dynamically to control flight attitude .. like a hang glider. I bought 3 Dunhaven gyro-servors for a future gimbal build .. perhaps a GS-1 would be helpful to "automate" that function .. servo input would just be for "trim".

http://www.dunehaven.com/gs1.htm .. If he's out of stock, try kapshop.com (Norway .. also had stock of GS-1 CR).

Cheers
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Old Feb 02, 2013, 03:14 AM
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Thank you, here is a preview of what's to come. The Radius (made from a salad bowl) just sitting there drying, it is freshly painted.
Perhaps a candidate for a CF layup .. duct and shroud combo .. nice.
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Old Feb 02, 2013, 05:18 AM
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i have bought a 10.375 ID x 48 long, cardboard cement tube, i plan to have 0.185 inch clearance for my 10" Dia MA tri-props...

This looks cheaper and easier than carbon fiber... and at 10.375 x 1.2 inches i can make many ducts quickly...

( on my table saw, i should get 35-ish ducts off a single 48 inch long tube )
Yea, the cardboard tubing is not as light as I would like however, I have not found anything else at the local hardware store what would work in the diameters required for the prop sizes used. I would love to work with fiberglass but just have not ventured into that area yet.

I am cutting the tubes to 2.5" presently but I am going to try some 1.75-2.00" in an attempt to reduce weight.
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Old Feb 02, 2013, 05:19 AM
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subscribed. Clever application .. shifting weight dynamically to control flight attitude .. like a hang glider. I bought 3 Dunhaven gyro-servors for a future gimbal build .. perhaps a GS-1 would be helpful to "automate" that function .. servo input would just be for "trim".

http://www.dunehaven.com/gs1.htm .. If he's out of stock, try kapshop.com (Norway .. also had stock of GS-1 CR).

Cheers
I love these servos and spent many nights dreaming about them. Just never made the investment. Then I came upon the Arduino with the MWC firmware, then there was no need for them.
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