HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Aug 13, 2012, 06:46 PM
Registered User
Tom Eutsler's Avatar
Asheville,NC
Joined Jun 2002
829 Posts
Reflex

I have done a search on this forum but as of yet , can not find a starting amount

for Reflex on the elevons

I went thru building instructions at CTH as well

Any suggestions ? thanks ................te
Tom Eutsler is offline Find More Posts by Tom Eutsler
Reply With Quote
Sign up now
to remove ads between posts
Old Aug 13, 2012, 08:01 PM
wheeeeee!
elCapitan's Avatar
United States, UT, Provo
Joined Oct 2011
916 Posts
Almost all these CTH will fly fine for a maiden with "slight reflex." in other words, slightly higher than the angle of the top of the wing. then just trim it in from there.
elCapitan is offline Find More Posts by elCapitan
Reply With Quote
Old Aug 13, 2012, 08:48 PM
Registered User
Tom Eutsler's Avatar
Asheville,NC
Joined Jun 2002
829 Posts
Reflex

Quote:
Originally Posted by elCapitan View Post
Almost all these CTH will fly fine for a maiden with "slight reflex." in other words, slightly higher than the angle of the top of the wing. then just trim it in from there.
It took me awhile on the Assassin to get it right but flys nicely now
same with the GR

This one is so little , figured it would not be much ..
Tom Eutsler is offline Find More Posts by Tom Eutsler
Reply With Quote
Old Aug 13, 2012, 09:24 PM
Registered User
Joined Aug 2005
957 Posts
Quote:
Originally Posted by Tom Eutsler View Post
This one is so little , figured it would not be much ..
My Scythe flys at 6 1/2 oz, Keda 2730-1700, TP G6 3S 480. It has almost 3/8" reflex (zero throttle) with a throttle - elevator mix that decreases reflex to ~3/16" at full throttle. Without the mix, the reflex that allows it to fly slow had it climbing like crazy with throttle. Has a mix for a little R aileron over 1/2 throttle too.
t.edwards is offline Find More Posts by t.edwards
Reply With Quote
Old Aug 14, 2012, 10:30 AM
Lee
PERFECT LANDING !!!
Lee's Avatar
USA, UT, Orem
Joined Jul 2004
9,048 Posts
It might be a little nose heavy if you need that much reflex.

How much does it weigh?

Thanks for the update.
Lee is offline Find More Posts by Lee
Reply With Quote
Old Aug 14, 2012, 12:19 PM
Registered User
Joined Aug 2005
957 Posts
Quote:
Originally Posted by Lee View Post
It might be a little nose heavy if you need that much reflex.

How much does it weigh?
CG is right on 5 1/2". Flying weight is 6 1/2 oz.

Trimmed for full throttle, which is fairly fast, Keda 2730-1700, 3S, APC 5.5 x 4.5, I have 3/16" reflex. That's saying zero reflex is with the bottom of the elevon being flat (same plane) with the bottom of the wing.

Thrust line is parallel with the bottom of the wing and ~.400" above the bottom of the wing.

Flys nice. 3/4 throttle and some up elevator and it will literally fly out of my hand, no "toss" required. The 3/8" reflex (actually slightly less because the throttle - elevator mix is set for 3/8" reflex at zero throttle dropping to 3/16" at full throttle) is what it wants flying with minimal throttle, just above stall speed.

At part throttle if seems to fly forever on a 480 mah battery. Good glide path. I like it.
t.edwards is offline Find More Posts by t.edwards
Reply With Quote
Old Aug 23, 2012, 08:39 AM
Registered User
Tom Eutsler's Avatar
Asheville,NC
Joined Jun 2002
829 Posts
Nose Heavy

Quote:
Originally Posted by Lee View Post
It might be a little nose heavy if you need that much reflex.

How much does it weigh?

Thanks for the update.
Lee, what would you suggest as starting point on reflex ?? Mine is finished now

and a tad nose heavy - Push pins on CG, if ya push on tail it comes back up to level . then push on the nose and it slowly comes back up/in other words it does not bonce back to level as quick

Thanks tom
Tom Eutsler is offline Find More Posts by Tom Eutsler
Reply With Quote
Old Aug 23, 2012, 06:56 PM
Registered User
Tom Eutsler's Avatar
Asheville,NC
Joined Jun 2002
829 Posts
Little Scythe

I played with the cog this am, as it seemed a bit nose heavy when resting on push pins beneath the wing , so I cut a length of solder and taped it on the back
The reflex [ did not measure it- used the tlar formula] and had both up an even amt
Used a MicroDAN 1804-2500Kv motor with a GWS 5x3 DD prop

and a Motrolfly 10A ESC from Micro Dan , a 1300 3 cell Nano Tech Batt

Had my GR friend maiden it , while i used the ifone to document flight or Krash

Dern thing took to the air right "out of the box ", then I got holt of the Tx and continued flying for 9 to 10 min . Battery showed 3.9 v on each cell after flying

Neat little wing, when done flying ya can almost stik in ya pocket and go home
Tom Eutsler is offline Find More Posts by Tom Eutsler
Reply With Quote
Old Aug 26, 2012, 12:09 AM
My dog ate my airplane
United States, CA, San Diego
Joined Dec 2008
201 Posts
I just finished a flew my first ever wing this morning, it's an old 30" beta version of the Scythe, and I did some studying of this thread first to find out what I would need to build it fairly light for slower flying in the small park nearby. I used the following gear:

HXT 500 5g servos
Turnigy 1811-3800 10g outrunner, very mall but surprising power!
GWS 4x2.5 prop
HobbyKing Orange 4 channel, Spektrum friendly RX, it's the smallest one they make that takes regular servo connectors, I think it's maybe 5g?
Turnigy Plush 10amp ESC, I think it's maybe 9g?
And a Zippy 2s 800mah 20c lipo, I was planning on trying to use a 350mah 2s, but it needed the extra weight in the nose to get the CG right on the spar, (4.5" from the nose).

I went light on the build of the airframe too and didn't use any extreme tape. I just laminated the leading and trailing edges with 2" wide strips of laminate and then 2 layers on the elevons for stiffness, and I just used regular packing tape on the laminated trailing edge for hinges. I did do the shock cord, but don't plan on doing combat with this, so it maybe wasn't necessary? Anyway despite the intentional light weight build it still seems very durable, I had a few cartwheel landings on my maiden flight today and it was no worse for wear afterwards.

I did some power off chuck glider flights with the battery just taped on to figure out CG and elevon trim and then ran home and cut out the battery mount and went back for power on flights, and it didn't seem to need any trim at all, it just flew like it was on rails, it wasn't what I expected and was pleasantly surprised by it. Thanks for a great kit Lee, it was fun to play with this morning and although I'm not a great pilot, this little wing should help me improve my skills a bit I think? Now I want to build more CTH airplanes, I may try my other Scythe with a front motor after seeing the Roswell with that setup? And I suspect it will be easier to get the CG with a front motor, which may allow me to use my little 350 2s batteries for an even lighter wing?
sredlin is offline Find More Posts by sredlin
Reply With Quote
Old Aug 26, 2012, 12:19 AM
My dog ate my airplane
United States, CA, San Diego
Joined Dec 2008
201 Posts
Also don't ask me how much it weighs, I don't have a postal scale to find out? All I know is that it's light enough to fly with that tiny outrunner I put on it, not unlimited vertical, but it goes pretty fast for the small park surrounded by trees that I fly in, and loops well from level flight.

I also do not know about current draw, I don't have a watt meter, but I tried a 6A ESC first and it was getting pretty warm pretty quick with just short test runs of the motor with the smallest prop I have for it 4 x 2.5, so I switched to the 10A ESC.
sredlin is offline Find More Posts by sredlin
Reply With Quote
Old Aug 26, 2012, 04:38 AM
Sorry, but they're all toys.
Eric Odle's Avatar
United States, WA, Bellingham
Joined Jun 2009
292 Posts
Your battery and ESC would easily support a 2211 or even a 2730 which is what I use. If you do decide to step up the power, the 2211 would be a good balance on the other side of an 800 mAH battery.

Also, that 1811 will start getting pretty hot at around 4 amps. I fly one on a smaller wing with the plush 6a ESC. You probably aren't drawing much more than that.
Eric Odle is offline Find More Posts by Eric Odle
Reply With Quote
Old Aug 26, 2012, 06:40 AM
Lee
PERFECT LANDING !!!
Lee's Avatar
USA, UT, Orem
Joined Jul 2004
9,048 Posts
Quote:
Originally Posted by sredlin View Post
I just finished a flew my first ever wing this morning, it's an old 30" beta version of the Scythe, and I did some studying of this thread first to find out what I would need to build it fairly light for slower flying in the small park nearby. I used the following gear:

I suspect it will be easier to get the CG with a front motor, which may allow me to use my little 350 2s batteries for an even lighter wing?
I have liked the front motor. Make sure you get your prop saver set up so the prop can easily fold down on impact and you will like it.
Lee is offline Find More Posts by Lee
Reply With Quote
Old Aug 26, 2012, 09:54 AM
My dog ate my airplane
United States, CA, San Diego
Joined Dec 2008
201 Posts
Lee, I was looking at one of your posts on the front motor mount on the Roswell and was wondering how that works with the shock cord, are you able to install it behind the motor mount with those acute angles?
sredlin is offline Find More Posts by sredlin
Reply With Quote
Old Aug 26, 2012, 09:55 AM
Suspended Account
Switzerland
Joined Aug 2012
173 Posts
sredlin, a cool plane. Glad to see you don't have a gyro. Mick
mikhail tupulov is offline Find More Posts by mikhail tupulov
Reply With Quote  (Disabled)
Old Aug 26, 2012, 10:10 AM
My dog ate my airplane
United States, CA, San Diego
Joined Dec 2008
201 Posts
Quote:
Originally Posted by Eric Odle View Post
Your battery and ESC would easily support a 2211 or even a 2730 which is what I use. If you do decide to step up the power, the 2211 would be a good balance on the other side of an 800 mAH battery.

Also, that 1811 will start getting pretty hot at around 4 amps. I fly one on a smaller wing with the plush 6a ESC. You probably aren't drawing much more than that.
Eric, I have a 2211 motor that's not doing anything right now, but I don't think I can get the CG without adding weight to the nose if I went to that motor, because it just barely balances on the spar with the 1811. I think it's probably due to my build which ended up with a lot of weight toward the rear of the airframe, I think my motor mount is heavier than it should be. I could probably try a 2211 with a 3s battery, but I'm pretty sure my flying skills and small field I usually fly in aren't up to that right now. I've been flying for a few years now, but most of my airplanes are relatively slow flying trainer and mild sport planes. So the 1811 seems to be plenty right now, as I spent most of my 20 minute flight yesterday at just over half throttle, which seemed fast enough for the flying site and my ability level, and the motor and ESC came down at room temperature. I should probably get a watt meter and try to get an idea of what the potential is with this combo, as I'm guessing by the cool temps at the end of the flight that there's room for experimenting with bigger props, but it's plenty of fun for me as is right now. Thanks for the feedback though, I may try that 2211 later, since it fits right in the same mount?
sredlin is offline Find More Posts by sredlin
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion RCG Project Mini/Micro Electric Helicopter Silverexpress New Forum Requests 26 May 13, 2010 02:53 AM
Discussion tekin mini rage vs mamba micro pro size imgumby Micro Cars 23 Mar 19, 2010 09:08 AM
Sold 2008 Edition T.O.P Racing Scythe ARP Touring Car FL62 Cars - Cars and Parts (FS/W) 0 Aug 18, 2009 08:08 PM
Video: The Scythe and the Stone Lavawing Slope 27 Nov 15, 2005 11:01 AM
Video: The Scythe and The Stone Lavawing Dynamic Soaring 0 Nov 12, 2005 01:54 AM