COX .020 POWERED FLYING WING

rdw777 wrote:That’s awesome TD…. I was into electric/foam wings for awhile…..You can get really high power to weight ratio with wings….. Nice and quick and still able to glide like a buzzard with power off….Looking forward to your .020 wing

good morning rdw

I was hoping to see a big weight savings compared to the Littlest Stick

It doesn't look like that will happen with this one.

I think it will still scream as you are being as weight conscious as possible…..I don’t have any wings at present to compare for a measuring stick, But I do have sort of a weird flying plate thing that’s maybe a little bit of a cousin to a wing….. It’s powered with a Bee which has similar power to your TeeDee .020….Of course the TeeDee revs a lot higher and your wing will have a lot less drag…. I use the charts below to compare Cox engines and is helpful…

The saucer weighs 11.39 oz and has 289 sq in area….

rdw777 wrote:

Robert, I have never seen this chart before, or if I saw it, promptly forgot about it. (Think it may be related to age.)

Thanks for providing it. It goes to show that the humble Pee Wee is a tad more powerful than the lighter but interesting .010 Tee Dee. But, I'd kind of expect that, as it is in reality a scaled down Black Widow, not the Babe Bee as some earlier engine article writers alluded to.

Also as I expected, the non-SPI cylinder QZ or QRC, forerunners of the R/C Bee, Ranger, Dragonfly, Sure Start, and Bee II's is a tad more powerful than the Babe Bee, which I found out when I got my R/C Bee back in the 1970's.

This chart is a good reference to keep on-hand.

That’s great George…. I forgot where I found it, Just saved it as a screenshot…. I think it’s fairly accurate…. Yes, Kind of neat that the PeeWizzers are not the expected  less than half of an .049 Bee but about 62%…. Little Black Widows indeed

rdw777 wrote:That’s great George…. I forgot where I found it, Just saved it as a screenshot…. I think it’s fairly accurate…. Yes, Kind of neat that the PeeWizzers are not the expected  less than half of an .049 Bee but about 62%…. Little Black Widows indeed

Your saucer flies great...!
Anything under 13 ounces ought to be pretty good with a .049 reedie. I flew RC Combat  with reedies  pulling 13 ounce flying wings and the action was fast enough without being a demolition derby. .
Here is a flat plate / pizza box flyer type plane similar to your Flying Saucer
With .049 reedie power / no throttle there was just enough power to hover this thing at  9 ounces and these planes were fun enough.
With the Norvel .074 installed this is what you got....pretty close to FULL BOOGEY 3D action

TD .020 power has been increased over stock.



Sep 29, 2018
Nano TD.020 Nelson Flat Coil Plug / HQ Carbon 3.6 x 4.5N Prop
Static: 24,870 rpm / 106 mph Pitch Speed / .083 hp / 62w
Static Peak: 25.113 rpm /107 mph Pitch Speed / .086 hp / 64w
4.6oz thrust .Bob Mattes Glow Plug Adapter / 30% Nitro / 20% oil
Thanks to the pressure tap the tank was bone dry when the engine
stopped providing steady rpm throughout the run.

Kamtechnik turbo plug adapter



Nov 9, 2020
Cox TD .020 / APC 4.2x2N
Good rpm @ 22,286 rpm
Static 6.8oz thrust with 42 mph prop pitch speed
Gen 5 turbo plug adapter test making good power with a
throttle sleeve from a Cox Pee Wee .020 engine.

1/2A Nut wrote:TD .020 power has been increased over stock.


Sep 29, 2018
Nano TD.020  Nelson Flat Coil Plug / HQ Carbon 3.6 x 4.5N Prop
Static: 24,870 rpm / 106 mph Pitch Speed / .083 hp / 62w
Static Peak: 25.113 rpm /107 mph Pitch Speed / .086 hp / 64w
4.6oz thrust .Bob Mattes Glow Plug Adapter / 30% Nitro / 20% oil
Thanks to the pressure tap the tank was bone dry when the engine
stopped providing steady rpm throughout the run.

Kamtechnik turbo plug adapter



Nov 9, 2020
Cox TD .020 / APC 4.2x2N
Good rpm @ 22,286 rpm
Static 6.8oz thrust with 42 mph prop pitch speed
Gen 5 turbo plug adapter test making good power with a
throttle sleeve from a Cox Pee Wee .020 engine.

 

Thanks for showing me what is possible...!
I swear I've never tached my TD .020 and would have guessed it turned the 4.2 x 2 prop some what more than 20K by ear.
In the 40 plus years I've been in this hobby I've owned 2 tachs, The last one only lasted about 20 plus years and now it's giving me some crazy readings.

250 mah 6.6v LIFE battery I use is small and only 13g



The wing looks good, the thick airfoil will slow it down some, up close flying with a throttle sleeve would be fun.
I would not exceed 70 sq in for peppy TD .020 projects.


Last one 200mah 6.6v

https://www.ebay.com/itm/356096858155?_skw=6.6v+life+battery&itmmeta=01J9XJ2V6Y7Q6B8EQGKN8M1P1M&hash=item52e906d82b:g:2yUAAOSwR7dmzhVR&itmprp=enc%3AAQAJAAAA8HoV3kP08IDx%2BKZ9MfhVJKmRrcx0QmhEPevAk%2FjupjRKINAaZF3YKU%2FkdnYAhOVIn3ILoWQvBNdi8JJiXgGHyRESc%2BVnPL616Hlti00ce0prEXAuSX0gIHjanEWATeyG45dHf7e%2F2Ds0FoWqW36PzfvS5%2Bb%2Fj4pthSJXOlJ0nZNFW3Z0SdbHmimzNQsSmWQW5qS38laD3iBiKDsTbKts1ier2Go4YX0FvHqemsqVqM0p1WqVQSrJc38WIFDcJKibrV4rLsZNCGAj3SkaDuLgWrMYT16J2aPB5KQPlspnZFrBnUDhcdDM5tGAFWtdloA%2Fzw%3D%3D%7Ctkp%3ABk9SR8yzi7LPZA

 

Wow TD!!… The .074 flying plate is pretty awesome!!..,, Very maneuverable to fly in and around the trees… Grest piloting, Above my pay grade

I notice your wing’s airfoil is fully symmetrical?….I always thought that might be a good idea…. Those I had in the past had a “wing” type airfoil…. They seemed to want to “tuck under” in certain situations if pushed a little much….Do you have a favorite CG calculator for wings?…..Kind of got me re-thinking wings….

rdw777 wrote:Wow TD!!… The .074 flying plate is pretty awesome!!..,, Very maneuverable to fly in and around the trees… Grest piloting, Above my pay grade

I notice your wing’s airfoil is fully symmetrical?….I always thought that might be a good idea…. Those I had in the past had a “wing” type airfoil…. They seemed to want to “tuck under” in certain situations if pushed a little much….Do you have a favorite CG calculator for wings?…..Kind of got me re-thinking wings….

I think 15% is a safe place to begin with flying wings. You might run out of elevator during the power off glide if it is too far forward, otherwise.
The further back you can put the CG the more extreme your aerobatics can get.
I always carry the 1/8" thick solder to make quick CG adjustments.
Extra prop washers can help too.
As far as airfoils go...unless you like doing outside loops and prolonged inverted flight [I do] then it doesn't make much difference which airfoil you choose. With 1/2A RC Combat it's more instinctive to fly "right side up" and to do inside maneuvers  once you find yourself really fighting to get on the other guys tail.
Flat bottom airfoils are  easier to build, easier to check for warps and easier to repair.
So, the "Clark Y" type airfoil with the flat bottom and the fully rounded airfoil up front is a nice blend of flying traits and convenience to build.
Here is a FLYING WING CG CALCULATOR....CG CALCULATOR
The Littlest Stick would make a great plane to try various airfoil types just to see the differences.
BTW...here is a AMA Fast Combat plane that I  converted to RC with a pair of elevons and vertical fins. Still running a Fox .36 Combat Special on bladder.....

getback wrote:Flying Saucers Flying Pizza Box looking thing OH MY ! The Box was crazy , The saucer was pretty cool Robert ! Both look FUN ! That Wing looks pretty wild TDA

I passed the PBF around to everyone that showed up at a Fly In...the PBF just had a Baby Bee .049 and no throttle...and everyone there was able to fly it looking like they had been practicing with it for a week. There is just something about those planes that  make them look hard to fly but the opposite is true. They are actually "hard to crash" just as long as you keep banking the right stick on the TX.

Thanks for your thoughts on wings and airfoils TD… Will have to re-visit that one of these days… I have a few TeeDee .020’s for candidates!!…. The Fox 36 Winger is just a beast!!…Scary! … Impressive!!

rdw777 wrote:Thanks for your thoughts on wings and airfoils TD… Will have to re-visit that one of these days… I have a few TeeDee .020’s for candidates!!…. The Fox 36 Winger is just a beast!!…Scary! … Impressive!!

I did the same conversion [with styrofoam  C/L Combat planes that were too heavy from repairs] to RC Flying Wing Combat with PAW .15 Diesel Power.
With 4 ounce tanks those planes were chugging around for about 15 or 20 minutes. You needed to really plan your attacks because gaining altitude back that you lost took time, the engines would get hot from too much tight maneuvering and lose a little power.
I'll bet the top speed was less than 60 mph flat out and more like 20mph while doing the tight "fur ball" maneuvering. The planes flew slowly enough to avoid mid airs, but most collisions didn't have enough impact to cause crashes.
During the summer we flew over chest high hay most of the time and there were times when a  plane that got knocked out of the sky would be hung up in the hay with the engine still running.. never reaching the dirt.
We towed pretty long string and crepe paper streamers....about 30 feet total. 30 feet doesn't look like much to aim for when flying RC.
There was no point trying to clean all the black, sooty residue off the planes. They just got more and more grotesque as time marched on.

I've been meaning to post a link to the covering material I used here.
https://valuehobby.com/covering

I think this stuff is a great deal and this supplier did a real good job of handling the very first order I placed with them.
I ordered 3 more rolls this morning.
Hopefully this supplier turns out to be a good one,,,they are new to me.

TD ABUSER wrote:I've been meaning to post a link to the covering material I used here.
https://valuehobby.com/covering

Just a quick look, appears to be the same type of stuff Hobby King was selling, commonly called by the modelling community as China-kote. I've used their covering, it is decent.

According to their website:

Value Hobby
1199 N Ellsworth Ave,
Villa Park, IL. 60181 US

means easier to order for US customers.

This caught my eye, https://valuehobby.com/25in-mini-delta-bee-arf.html

25in Mini Delta Bee Flying Wing ARF from Value Hobby website

Although for electric power, I couldn't see why it could not be converted to Cox glow engine power.

GallopingGhostler wrote:

TD ABUSER wrote:I've been meaning to post a link to the covering material I used here.
https://valuehobby.com/covering

Just a quick look, appears to be the same type of stuff Hobby King was selling, commonly called by the modelling community as China-kote. I've used their covering, it is decent.

According to their website:

Value Hobby
1199 N Ellsworth Ave,
Villa Park, IL. 60181 US

means easier to order for US customers.

This caught my eye, https://valuehobby.com/25in-mini-delta-bee-arf.html

25in Mini Delta Bee Flying Wing ARF from Value Hobby website

Although for electric power, I couldn't see why it could not be converted to Cox glow engine power.

About the covering...it works out to about a buck a foot and it's strong enough for open bays on our 1/2A planes but I'm not sure about using it on a 40 sized model.
That little delta you show is pretty close to one I built for my Cyclon .061 some years ago....the fuselage was fiberglass over foam and it bolted to a solid balsa sheet wing.
It flew TOP HEAVY, acting like it wanted to be flown as a high wing plane instead of low wing....


I think it would have been more stable if it had a shallow belly below the wing for the battery.
Now here is another 24 inch delta that didn't have as much side area and weight  above the wing so I think it was a better flyer.
Don't pay no mind to the rolling launch, that was just a lateral balance issue one wing panel was way heavier than the other....

Here it is all done [well done enough ] at a little less than 6 ounces
I needed to add some weight to the tail to set the CG at 15%.
I pounded a length of solder flat, then glued it to the fin.
The model flew pretty straight and stable with enough elevator during the glide to flare the landings at a low enough speed.
The model is a little too stable to tumble or spin.
I think swept wing flying wings tend to behave this way..[BEING TOO STABLE]but a more daring CG and bigger controls might fix this problem.... .
The symmetrical airfoil and 0 thrust line makes the rolls axial.

Very nice Chuck, the stock prop unloaded to a pleasing tone.

Can go faster with a thinner / stiffer APC 4x3.3E drone prop back cut as a 4x3.3N
Note the faint suggested cut line to scrub prop load.



Also helped a .020  Nano design project reach the following results with back cut as
a key mod to the props along with some dia. changes.

https://www.youtube.com/watch?v=xj3xS_qMhxk&t=1s
Jul 17, 2022

Vid rpm readings / prop E pitch N speeds:
- audio doppler readings
?x4.1N - 29,392 @ 1.02 mins. / 114 mph - 183.5 kph
?x4.7N - 27,051 @ 2.02 mins. / 120 mph - 193 kph
?x3N - 31,573 @ 5.48 mins. / 90 mph - 145 kph
4x3 - 28,667 / 81 mph - 130 kph

The current known Youtube radar speed record is 122 mph
-with a stock TD .020 / 3.6 x 4.5N

1/2A Nut wrote:Very nice Chuck, the stock prop unloaded to a pleasing tone.

Can go faster with a thinner / stiffer APC 4x3.3E drone prop back cut as a 4x3.3N
Note the faint suggested cut line to scrub prop load.

:

That's good to know..!
I like the idea of preserving the 4 inch diameter...yet still being able to gain speed.
The mod looks really simple....something I could do free hand with a belt sander resting on it's side.
I would finally treat myself with a bench top sanding station but I don't have the extra room for space hog tools.
I plan on rejoining a model plane club that is on the outskirts of town.
This is the only way that I'll ever be able to safely fly speedy stuff any more and even then I'll need to pick and choose my times to do that carefully since the runway has a busy highway less than 300 feet from one end.
It also looks like they have noise issues with nearby neighbors.


http://www.aercf.org/

Can recommend,

https://kamtechnik.com/product-category/cox-aft/cox-020/

-Prop drive hub locks a APC prop perfectly centered for max rpm. Also works with carbon CAM props.
-Reduced weight aluminum spinner nut adds rpm only use if the plane has been trimmed up and stable.
-Turbo plug adapter with proper turbo plug and shim count can exceed stock rpm.

Note I like end point hex head stubs with Valentine spinner prop nuts.
Can always remove them with a allen wrench and keep them tight so only the spinner nut
pops loose in the field during prop changes.

The aluminum tank provides good fuel flow to the engine for great rpm.
The alt is longer flights with a 15cc to 20cc bottle tank with a aluminum radial mount.









This is the shiz niz and only for pro performance nerds, speed freaks and perfectionist.



Freight train flying with a CAM 4x3 / 2.9oz RTF / 19.7" span
The last pic is from Europe. Nano version from Tobaiies a Swiss Cox TD .020 fan ref
previous vid link, he tested 4 suggested speed props with great results.

Update GPS Telemetry * 3.46oz - 98g RTF
- No wind day
80mph ground speed 129kph / CAM 4x3N
98mph -158kph / APC 4.1x4.1N

Onboard GPS gear used:
- SM GPS Logger 2 (11g)

Note alt. lower weight:
- Futaba R3004SB (4.8g)

   

1/2A Nut wrote:Can recommend,

https://kamtechnik.com/product-category/cox-aft/cox-020/

-Prop drive hub locks a APC prop perfectly centered for max rpm. Also works with carbon CAM props.
-Reduced weight aluminum spinner nut adds rpm only use if the plane has been trimmed up and stable.
-Turbo plug adapter with proper turbo plug and shim count can exceed stock rpm.

Note I like end point hex head stubs with Valentine spinner prop nuts.
Can always remove them with a allen wrench and keep them tight so only the spinner nut
pops loose in the field during prop changes.





Freight train flying with a CAM 4x3 / 2.9oz RTF / 19.7" span
:

Thanks to the links to that stuff...I was already in the process of ordering a backplate mount..!
That little racer looks so simple..might as well make 2 at a time..!

Would recommend sculpting in a real airfoil, note ply fuse with spruce sq. stock.
As shown below, way more stable.










May 28, 2018
TD .020 / 3.4 x 4.5 Prop best peak 28,585 rpm / 122 mph down wind best pass.
Heat was rough 96F Static in the hand at launch 23,192 rpm / 99 mph pitch speed
3ch with throttle sleeve 119g - 4.2oz RTF / 19.5" Span
43" Sq. In. / 15cc nylon bottle with rubber stopper tank.