Homemade EPP F-22 park flyer.

[akent]

This is the long flight at just under 4 minutes of video.
This thing flies great now! Pretty stable! I added more carbon fiber to a few areas of the jet.
What's really weird is how the motor reacted when I first fired it up and WOT. Anyone seen that before?


I didn't try any high alpha, as it was really windy, and this thing only now flies like it should!

Here's a shorter flight later on in the day.

Kent

[BTCat]

I gotta have one! That looks like super fun. Nice looking Scratch, Kent

[elkmaster01]

Kent,,, that looks ike a bunch of fun. You can toss it around without a worry. Sounds insane too. I'd like to build one,,but I have too much stuff now,,,I actually don't have time,,,LOL,,,been a few years since I could say that!!

[19000rpm]

She flies sweet. Did you use the Grayson V2 pkg.?

Maybe just a glitch with the ESC caused that false start. Just for kicks check the wiring under the shrink.

I have an ESC that won't initialize half the time without repeated tries, but when it does it works fine. Go figure.

[flyinghigh]

Kent, that is very cool, ...and loud! Watching all these planes and EDF's, makes me want one too! lol!

Some of you guys are so creative and mechanically inclined. If I don't have instructions, with pictures, ...well, I'm in trouble..lol

Btw, nice looking piece of land, ...I need to get out of the big city.

[dubehigh]

thats a hoot kent, sounds like a little .049 cox engine. l.o.l

[akent]

Yeah, the crazy thing is really loud, and now that you mention it, Dube, it does sound a lot like a .049!!
I will be looking into how to quiet the thing down. Maybe a different shaped slot?

19k, it's not the Grayson power, but the foam came from them.

Here is the build list:
Plans (I built the 24" version from EPP foam):
www.rcgroups.com/forums/showthread.php?t=740049

Foam (3 sheets, enough for at least 3 models):
www.graysonhobby.com/catalog/white-24x36-sheets-p-959.html

Motor (comes with prop saver and firewall mount):
www.hobbycity.com/hobbyking/store/uh_viewItem.asp?idProduct=4859

ESC (18 amp):
www.hobbycity.com/hobbyking/store/uh_viewItem.asp?idProduct=4312

Prop (8" 4 pitch):
www.hobbycity.com/hobbyking/store/uh_viewItem.asp?idProduct=10046

Servos:
www.hobbycity.com/hobbyking/store/uh_viewItem.asp?idProduct=662

Battery:
www.hobbycity.com/hobbyking/store/uh_viewItem.asp?idProduct=6471

Receiver:
Spektrum AR6110.

Carbon fiber tubes and flats from hobby city. I bought a bunch a while back.
====
So, the whole thing is around $90! And the electronics can be reused.
Another airframe will run around $8.

It took me one evening to cut out the templates and foam, hinge and paint the parts. Maybe 2 hours. The next night I assembled it and installed all of the electronics. Maybe 2 more hours.
It took two batteries and a little more carbon fiber to get it like it is now. Maybe another hour.
The next one I can build in probably 2 hours for everything (the templates are reusable, too), but I hope this one will last a while.
Best,
Kent

[19000rpm]

Thanks Kent

[BTCat]

I like the way it sounds, but I bet you could muffle it. Like you mentioned, changing the shape of the slot might work. If you tapered the back part of the slot on the top and bottom and maybe even on the two sides, I'll bet it would quieten some. If it were mine, I might V the edge back to about a 30 degree angle. It would be an interesting test. The sound could be resonating through the mount, too

[akent]

Hey BT, if you want one, I could send you this one and I could make another one in maybe a couple of hours. Or, you could head on down here and we could build one for you in no time!

I know how durable this thing is, because on it's maiden, I didn't know how to throw it yet, and at full throttle, it took a nosedive straight into the ground. I did NOT repair anything after that! It is in the videos as it was after that crash!! The nose of this one is 2 layers of EPP with a carbon tube down the middle to make it more rigid.

These things are amazing!

Oh, I did order a 3kv motor along with some smaller props a few days ago. I hope to find out what makes these things either fast or able to do 3d. This one 'should' be able to do 3d now, but it's been so windy there has been no chance to figure that out.

I would like to build a 3d version, and then a really fast version with the motor coming from HC.

At least I can fly this thing when it's too windy to fly anything else, as I did today with major winds!

Take care,
Kent

[BTCat]

Nice offer, Kent, but I'm going to wait until I can build one. Half the fun to me is the build. Kind of ironic that I don't seem to have as much fun during the repairs

Don't know about driving to Austin. There's some wierd people down there ;D

[19000rpm]

OK guys, The 9mm foam for the F22 is going to be here on March 3rd.

I think I'll build it with my 2200kV motor, a 6X4 prop, 30A ESC and 1300 or 1500mAh battery. That baby should smoke and do some high Alpha too. Should be able to do super 3D with the 8 prop.

I was wondering if you used the carbon tube on the fuse Kent. What did you use across the wing?

[akent]

Just got back from flying everything!
It's a beautiful day here, low 60's with 5-15mph winds. A little windy, but not bad!
I'm uploading some high alpha F22 vids now. I'll post a link when it's done.

Anyway, in the wing, I used a long 5mm CF tube towards the rear and a 3mm tube towards the front, as shown on the plans. On the leading edges, I used 5mm wide flat strips. In the fuselage I used 3mm square. I also built a triangular cage like thing on the bottom but that wasn't stiff enough for me, so I put 3mm squares on the top. I didn't bury those on the top, as the bottom triangle was buried.
Edit: There's more! The bottom strakes have a 5mm flat CF strip along them, and the rudder has a 2mm flat strip along the leading edge.
So, it's all probably overkill, but the thing is very rigid. It hardly flexes, even in higher winds.

My F22 has unlimited vertical with the above parts, but it's not that fast.

Your motor kv and power sounds perfect, 19k! Which motor is it?

I think you are going to love this thing! I had three crashes with the F22 today doing high alpha and there is zero damage! One crash was HARD, too!
Kent

[Solitaire]

I'm betting it's this motor, Kent.
I'm using two of these in a redone Big Lama on 3S and they are light and powerful. I think they'd be excellent in this application.

www.xheli.com/al2502oubrmo.html

[akent]

There's some high(er) alpha flying with TWO crashes! I had one other faster crash earlier on when pulling out of high alpha in a wind gust.

ZERO DAMAGE all day! I crashed all of my foamies today in the wind, trying new things. I did dumb thumb the Delta Dart, but the rest were just learning high alpha. I wouldn't even THINK about trying high alpha with a 'real' plane!

Man I love this EPP stuff! Oh, I did find a small tear in the Yak55 when inspecting these things before going out. Well, fire up the hot glue gun and in about 5 seconds that was fixed! I LOVE IT!
Kent