Foamboard Scratchbuild University - Page 159 - RC Groups
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Jan 11, 2013, 07:27 PM
Registered User
A quick question for the experts.
I am building a twin using the Armin Wing with a cord of 7.5 inches. The fuse is flat on the bottom front section and that is what I refer to as the datum or 0 Degree's and the Armin Wing being flat on the bottom, should I run a small amount of + degree's on the wing, say 2.5 degree's?

Also think that about 2 or 3 degree's negative on the motors would work things about right, yes, no?

Thanks for your time, first dollar foam anything that I have done, so far have just made a mess. LOL

Jim
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Jan 11, 2013, 09:24 PM
Ed @ Experimental Airlines
ExperimentalAir's Avatar
Quote:
Originally Posted by JamesBC
A quick question for the experts.
I am building a twin using the Armin Wing with a cord of 7.5 inches. The fuse is flat on the bottom front section and that is what I refer to as the datum or 0 Degree's and the Armin Wing being flat on the bottom, should I run a small amount of + degree's on the wing, say 2.5 degree's?

Also think that about 2 or 3 degree's negative on the motors would work things about right, yes, no?

Thanks for your time, first dollar foam anything that I have done, so far have just made a mess. LOL

Jim
Hi Jim,

I love me some twins! I might recommend leaving the wing and the thrust angle at 0% and if you are concerned, build in a little negative incidence in the horizontal stabilizer. I can confess that every plane of my design has 0% alignment between the wing lower surface, fuselage, and horizontal stabilizer, and it seems to work OK on the scale I am using. That's not to imply that some variation might not be slightly advantageous, only that a simple triple-alignment is easy and at least workable. Some downthrust might actually be advantageous too, but I always leave my multimotors at 0%. Take a leap and let us know what you think!

Peace,
Ed
Jan 11, 2013, 10:59 PM
Registered User
Thanks Ed, and a big thanks for posting the video's on how to.

I will set the wing at zero but think I might leave a little down on the motors as they are maybe a little over kill for a 50" wing. But hey, can always fly at half throttle.

The first one is more a test bed to try different things out. I have figured out that the twin wing and fuselage is costing about $5.00 so can afford to build it several times.

Thanks again for all the work you did Ed.

Jim
Jan 12, 2013, 12:37 AM
Wait...what?
gbmarsh's Avatar
Hey neighbor! What's the spec on the motors you are planning to use?
Oddly, I've been mulling the idea of building a twin lately... must be something in the water 'round these parts

(off topic) Where do you fly around Abby?

Cheers,
Geoff
Jan 12, 2013, 12:56 AM
Registered User
Quote:
Originally Posted by gbmarsh
Hey neighbor! What's the spec on the motors you are planning to use?
Oddly, I've been mulling the idea of building a twin lately... must be something in the water 'round these parts

(off topic) Where do you fly around Abby?

Cheers,
Geoff
Have you tried the wing build with foam board, LOL, took me all of about half an hour to finish one wing panel. Using Ed's wing design and then fuse design is from this thread https://www.rcgroups.com/forums/show....php?t=1181441
kind of a mix and match bird...

Like I said, first one is rough but only to try out the design, next one will take more time and pretty it up.

Kind of plan on using two 2215 900kv 200wat on 3S. More than enough power and might have move down on motor size, the wing span is 50" and fuse is 36" nose to tail. But to tell the truth, using foam board is so cheap and so easy, can build it different if need be.

I am a member of the Aldergrove Prop Nuts, we have a field over on 264th. Only right now its to wet to fly there so good time to build.
Jan 12, 2013, 01:27 AM
Wait...what?
gbmarsh's Avatar
Quote:
Originally Posted by JamesBC
Have you tried the wing build with foam board, LOL, took me all of about half an hour to finish one wing panel. Using Ed's wing design and then fuse design is from this thread https://www.rcgroups.com/forums/show....php?t=1181441
kind of a mix and match bird...

Like I said, first one is rough but only to try out the design, next one will take more time and pretty it up.

Kind of plan on using two 2215 900kv 200wat on 3S. More than enough power and might have move down on motor size, the wing span is 50" and fuse is 36" nose to tail. But to tell the truth, using foam board is so cheap and so easy, can build it different if need be.

I am a member of the Aldergrove Prop Nuts, we have a field over on 264th. Only right now its to wet to fly there so good time to build.
Heh, I've looked at that Jackal as inspiration for a twin as well, nice design. I have a couple of wings built using Ed's design already, one is a 7" x 30" for a Funbat-ish model and the other is a 8" x 44" wing for my HZ SuperCub. Both planes are waiting for some nicer weather for maiden flights.

Your twin should have lots of grunt with those motors, please post some pics if you can.

Cheers,
Geoff
Jan 12, 2013, 09:45 AM
Registered User
jetcommander's Avatar
Quote:
Originally Posted by smittyplugs
well this was a gut wrenching feeling lol

http://youtu.be/H8xJaOSXD2w
Hey smittyplugs IŽm sorry for you, that was such nice footage and it was really stable, man I thought you were going to hit the top of that monster mushroom. YouŽll be up and flying again in no time.
Jan 12, 2013, 09:47 AM
Registered User

Check out the Snow Mad


Check out the Snow Mad.
Last edited by Mighty Wind; Mar 23, 2013 at 05:39 PM. Reason: Deleted video from YouTube
Jan 12, 2013, 10:59 AM
Registered User
Quote:
Originally Posted by Vance1
For my push rods I go to Home Depot and get Empire Stake Flags 100 Pack for $7.98 a bundle.
...fantastic... What type of clevis do you use? What method do you use to secure the clevis to the stake flag rod?

Thanks!
Jan 12, 2013, 11:07 AM
Registered User

Target CG position for the Axon?


I'm guessing that the CG for the Axon should be below the thickest point of the forward wing (point of maximum wing curvature).

...or is there some other applicable rule / principle?

Thanks!
Jan 12, 2013, 11:50 AM
Registered User
smitty919's Avatar
Quote:
Originally Posted by jetcommander
Hey smittyplugs IŽm sorry for you, that was such nice footage and it was really stable, man I thought you were going to hit the top of that monster mushroom. YouŽll be up and flying again in no time.
Thanks Jet.....
Good news is i fixed it last night and just got back from the 2nd maiden lol was a little to windy but did get one flight in with a different receiver mounted in the plane and she did great.....TOOK HER HOME IN ONE PIECE lol
Jan 12, 2013, 11:52 AM
Registered User
No clevis, Dubro E-Z connector on control surfaces for adjustment and Z bend at servo.
Jan 12, 2013, 12:15 PM
Registered User
Quote:
Originally Posted by Vance1
No clevis, Dubro E-Z connector on control surfaces for adjustment and Z bend at servo.
Nice...

Thank You!
Jan 12, 2013, 12:30 PM
Registered User

Check Out The Snow Mad


Check out the Snow Mad.
Last edited by Mighty Wind; Mar 23, 2013 at 05:40 PM. Reason: Deleted video from YouTube
Jan 12, 2013, 12:49 PM
Registered User
smitty919's Avatar
The 2nd maiden flight of the "Slow Go Pro 60" it was windy and was trying to feel the plane out sorry for the shaky video...Next will be to ad the flight stabilizer

GoPro Plane (5 min 25 sec)


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