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Old Jun 24, 2014, 05:02 PM
I don't like your altitude
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HoXVIIIB

I made a start today,just dry fit to see how things go together.
I've asked a guy to turn me a tapered mandrel(probably nylon) to form the exhaust ducting.
I'm hoping to use plastic sheet,what type do you guys recommend?

btw this turned up on flying wings a while ago-

http://www.rcgroups.com/forums/showthread.php?t=2179814
I've started a build log on the Nurflugal forum,I'll keep this up to date too.
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Last edited by Stupot46; Jun 26, 2014 at 01:22 AM.
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Old Jun 25, 2014, 03:17 AM
I don't like your altitude
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Maths check please. (All figures rounded)

Fan dia. 55mm=2376 sq
Stator hub. 26mm= 531 sq
FSA. 1845sq= 485mm dia.
@90% exhaust dia 44mm

From what I've read on here 90% should be ok for this type of set up?
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Old Jun 25, 2014, 09:26 PM
Fremont, CA
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The link doesn't work for me :-(
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Old Jun 26, 2014, 01:23 AM
I don't like your altitude
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Originally Posted by djacob7 View Post
The link doesn't work for me :-(
Sorry about that,messed it up with a smiley. ok now.
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Old Jun 26, 2014, 12:38 PM
Fremont, CA
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Very impressive build!
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Old Jun 29, 2014, 06:21 AM
I don't like your altitude
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Bit of an update,the pics.tell the story.
A guy on the forums is printing some rings which will slip over the fans to give a smooth airflow from the nacelles.I had a go at making a balsa/Lt ply one but it's hard to achieve a smooth outer curve at this size.
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Old Jul 01, 2014, 05:50 AM
I don't like your altitude
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Thought you guys might like these.Brian(cpdude) converted my sketch into a file which Chris(B11TME) used to print these inlet rings for the fans.
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Old Jul 03, 2014, 05:38 AM
I don't like your altitude
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Joined Sep 2011
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The hardwood mandrel for the ducting.Nice piece of turning,super smooth!
Ground steering will be a problem with this,I'd previously thought about skid steer or air brakes behind the exhausts.Then I had a Homer moment and realised differential thrust could be the answer if I can set it up to switch off for flight.The transmitter I've used is an Optic6 sport,which has been ideal for simple flying wings.Im not sure if it's got the capability to do the mix,I've posed the question in the radio forum.
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Old Jul 05, 2014, 08:06 AM
I don't like your altitude
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Made up the first duct.I cut the plastic to width with a 5mm overlap.Used come double sided tape to get the seam with it wrapped around the mandrel.Trimmed the ends against the ends of the wood and wrapped the exhaust end with trim tape.
To join this to the fan I taped and waxed the fan body and gave it a couple of wraps of Kevlar tape using finishing resin.When this was touch dry I eased it off with a thin blade and set it onto the duct.Ive left it to harden with the mandrel back in.
Edit-I managed to get a dry fit of the unit,it's come together ok
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Old Jul 06, 2014, 11:37 AM
I don't like your altitude
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I completed the other fan bearer ,so slid the pylon in place to check the fit.All good so popped in some wheels and the door framework.
Now to get the other pair to the same stage.
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Old Jul 06, 2014, 10:56 PM
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Brakes for steering... as used in a Tank ?
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Old Jul 07, 2014, 12:54 AM
I don't like your altitude
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Originally Posted by Bare View Post
Brakes for steering... as used in a Tank ?
Still debating that one.
1-skid steering- 1wheel in 4? How much effect would it have,especially on an uneven surface.More than 1 wheel means more mechanism/weight.
2-air brakes-opening vanes behind the outer fan exhausts.- simpler to install/set up.Servo to open,rubber band to close.Lighter than 1.
3- differential thrust-lightest option.Works on water!It would need a mix in the transmitter and a switch to isolate it whilst in the air.Current favourite.
Ill probably try and go with this but put the wiring in for 2 as an option.
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Old Jul 21, 2014, 09:51 AM
I don't like your altitude
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Gear doors H XVIIIb (0 min 34 sec)


Short video of the gear doors working.
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Old Sep 01, 2014, 07:49 PM
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Stu...are these your own plans? I like the off-beat and unusual..I'll be checking in from time to time.
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Old Sep 02, 2014, 05:33 PM
I don't like your altitude
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Originally Posted by 335driver View Post
Stu...are these your own plans? I like the off-beat and unusual..I'll be checking in from time to time.
http://www.rcgroups.com/forums/showp...7&postcount=89
Regards Stuart
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