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Posted by FeiJi | Oct 07, 2015 @ 10:06 AM | 1,474 Views
I need someone to make me a gyroscope rotor like the attached photo. Needs to be about 5 inches in diameter and half inch thick and the center hole would fit a prop adapter (l need to get size of the adapter yet). Material could be aluminum, brass or steel. Please pm me your price. Only need a one-off but perhaps a couple more in the future.
Also attached pdf of specs.

Update: found a source to make the rotor for me for 105$.
Posted by FeiJi | Aug 06, 2015 @ 08:36 AM | 1,469 Views
I flew this asymmetric tailed flatplate delta and it has an obvious flight behavior - can you guess what it is?

Rolls great to the right but if try roll to left it death spirals. Too much drag to the left I guess.
Posted by FeiJi | Aug 01, 2015 @ 09:34 AM | 2,029 Views
Back from China now and no access to cheap EPP foam so resorting to Dollar Tree foam. Don't know AUW. About 20" WS. 1800kv motor with 7x5 prop and 1000mah lipo. Flies ok , nice roll to right but not to left because am using paperclip control rods and they give sloppy control. Going to get little bike spokes and beef them up but not bad for an hour of work, at least am flying.
Fin is asymmetric but seems ok, dont think it affects weird roll to left but will find out when I replace rods.
Posted by FeiJi | Jul 26, 2015 @ 10:18 PM | 1,572 Views
Someone may have missed seeing this concept delta(s) video from last year.
Future Concepts - The Transformer (0 min 48 sec)

Posted by FeiJi | Apr 26, 2015 @ 03:23 AM | 2,489 Views
Well my hatcam worked but couldnt be sure where it was pointing so made this adapter for my glasses and it works quite well. An adapter would make a nice 3d printer project as mine is a little heavy.

Video is some noodling around with my new plank wing. Flew over 12 minutes with many takeoffs on a 2200mah lipo. Going to see if I can break 20 minutes on a single flight.

Boneyard Plank EPP Wing (12 min 49 sec)

Posted by FeiJi | Apr 24, 2015 @ 02:56 AM | 2,628 Views
Finally after screwing up the fuselage angle and flying a loop which forced me to dive for the ground to avoid being hit,I got it flying. It takes very little powerfor takeoff and cruise and is easy to control.
The video is just a few cuts of takeoffs because my hatcam was askew and I took picutures of empty space.
Boneyard Plank EPP Wing (0 min 34 sec)

Posted by FeiJi | Apr 18, 2015 @ 12:02 AM | 3,573 Views
Working on a plank using 9mm epp foam laminated with copyshop laminate and it also has a carbon fiber pole frame and spar. Should be stout enough yet still plenty light. I tried to make it without the front middle section but just couldnt get enough weight forward to balance. Now have lots of space to play with cg. Also it is a prop in the slot configuration as if that is not obvious. Should be very noisy but I'm in china where it is already noisy.Going to add a vertical stab on this one. I love how planks fly.
Posted by FeiJi | Mar 15, 2015 @ 04:04 AM | 4,675 Views
Here is a neat little poster I got here in china in a bookstore of the P51 B.
Unfortunately it is printed on brown paper so hard to read but I took some closeups for you aficionados.
Posted by FeiJi | Feb 19, 2015 @ 09:22 PM | 4,372 Views
Getting 15 minute+ flights from my 40" wing.
AUW is 750 grams but 120 of that is dead weight in the nose under the battery. So I could replace that with another 2200 3s lipo and get 30+ minute flights but that would tax my neck.
Motor I think is 1800kv, 40amp esc 7x5 prop.
Spars are fiberglass fishing pole sections, very light and strong.
Wing was then covered with laminate film. Very strong and flies very well.
Posted by FeiJi | Feb 05, 2015 @ 02:56 AM | 4,773 Views
Just some noodling around with my new BoneYard 6 40" EPP wing with big tube spars. No fins. No expo - I like my sticks touchy. Not a good place to fly, too many obstacles.
40 Inch EPP Wing with Big Tube Spars - Noodling Around the Sky (4 min 59 sec)

Posted by FeiJi | Jan 17, 2015 @ 09:29 PM | 4,379 Views
My first hatcam finally died, rip, and I bought another keychain camera (dont know which one) last year but the battery died very quickly.
So made it into a hat cam with external battery.
Just opened up the case, unsoldered the original battery leads, soldered in it's place a female JST plug , hotglued the wires to the circuit board so they won't pull out, and away we go.
I like the external battery because I can user bigger mAh lipo for long life between charges.
The battery is under the cap held in the liner by the spring clip.
Bolted and zip-tied camera to the hat.
I had to get rid of my MGB but kept the hat. Both have seen better days.
Posted by FeiJi | Jan 03, 2015 @ 01:26 AM | 2,808 Views
Wow, still tail heavy but I can tell it's got great glide. Add a little more nose weight, and clean up the end of the wings (one still has some extra length of tube spar sticking out) - guess I should be surprised it flew at all. Now 700 grams so will probably end up at 750 but that will handle wind well and it still will glide great
Update: 1/11/2015 - another 50 grams did the trick - it flies beautifully now. Just have to get my camerawoman back. Love flying finless.
There is so little sweep that it is basically just a flying plank. CG has to be spot on. I knew that.

BoneYard 6 EPP Flying Wing Maiden (0 min 34 sec)

Posted by FeiJi | Nov 17, 2014 @ 09:38 PM | 3,220 Views
AUW 615 grams. About 400 sq inches area. 1800 kv motor, 40amp ESC, 2200 3s lipo, Radio is inside wing. Just don't have camera anymore for maiden so will have to get someone to video or attach my camera to my tx somehow.

First flight didn't go well as too tail heavy. Same story with first one I built as it has low sweep and needs forward cg - almost as much as staightwing tailless plane.
I will add couple ounces and it should be fine. This size wing carries more weight easily and doesnt effect flight time much. I expect to hit 20 minute flights with this battery as my last wing of this configuration hit 18 minutes on an 1800mah lipo..
The truth is in the testing I guess.
Posted by FeiJi | Nov 12, 2014 @ 07:06 PM | 5,263 Views
Finished the airframe and ready to add controls and electronic stuff. Weighs 260 grams without any equipment. About 400 sq inches and should be final AUW of 600 grams. This is my BoneYard 6 wing. This will be finless like my other wings.
Posted by FeiJi | Nov 09, 2014 @ 05:57 AM | 3,689 Views
I gave away my last 40" wing when I moved and enjoyed flying it so much I had to build another. Reinforced this one with carbon fishing pole sections - so strong I can't bend the wing and I haven't even laminated it yet. With the big tubes (which add very little weight) and little flex, this feels more like a real airplane wing. This one should last a few years.
Posted by FeiJi | Oct 20, 2014 @ 08:10 PM | 3,226 Views
I needed to refurbish my year and half old wing center section and decided to use two sections of lightweight fiberglass fishing pole to shore up the center section. Wow, amazed at how strong it is with them hotglued in and I havent even laminated the center section yet. Do believe it would be plenty strong enough without the laminate. Pictures shows one rod where I left out foam so that I could sink my ESC and radio into the fuse, the other is further back under the foam. Much better than thin carbon fiber rods or flats or barbeque spits.
Posted by FeiJi | Sep 05, 2014 @ 04:35 AM | 4,184 Views
Well it's together. Tail is off by 1/8 inch, wing too far back by 3/16, got some wrinkles in the wing laminate because I dont have a heat gun. But it is very strong. Surprised it came out as well as it did with just a clothes iron.
Wish I had an ugly contest to enter it in.
AUW is 145 grams but may need a little ballast. Could easily have left out the carbon spars as the laminate makes the wing plenty strong enough. I glided in on my bed and swung it around by the peg. The vertical stab should hold up as I doubled the laminate there.
Just have to install servos.
Not too bad considering no instructions. I suppose I could do another one now that I know how it probably should be build.
I dont expect it to be an amazing flyer but hopefully it will get me a little further along learning how to fly dlgs. I expect it will fly better than my fake alula.
Probably wont get to maiden till nxt week so I can just anticipate good things happening.
Posted by FeiJi | Aug 30, 2014 @ 01:41 AM | 3,984 Views
I am in a temporary apartment and don't have any real tools or workspace but decided to start putting my glider together anyway seeing as how it's so cheap, I can afford to make some mistakes - and I did.

I have no instructions but with a little thinking about it, the parts just kind of put themselves together. The fuselage was a no brainer and the pieces fit great.

I have no jig but the wing went together pretty easily though I messed up the LE and decided to remedy it with a piece of balsa I had to cut to add to the LE, and then to leave off the wing sheeting on the LE. The wing will still be very strong because I put in a carbon fiber slat wingspar and I am going to be using laminating film to cover.
Just need to do some sanding.

Have all major components assembled and comes out to about 110 grams without electronics.

Now if they had only sent me the other wing.
Posted by FeiJi | Aug 28, 2014 @ 01:56 AM | 4,964 Views
(Please note that I am working in china so do not know if or how this may be available in US.)
I got this 160rmb dlg balsa kit in china on with no instructions.
Think I have figured out where all the parts go from looking at the picture. Just not sure how far the fiberglass boom goes inside the fuselage. i can figure out the cg. Will use copy shop laminate to cover I think. Can hardly go wrong for the price.
Pretty complete kit, even a couple magnets for the hatch.

Have started building the fuselage, going together nicely.
Posted by FeiJi | Jul 26, 2014 @ 08:30 AM | 4,680 Views
Ha ha. Not really. Black epp looks like asphalt though.
I'm in china and got this Alula like plane kit for 80rmb ($13) from
I have been flying about 4 years but never done a glider and I moved to a new part of china and didnt have anything with me except my transmitter and a receiver. So ordered this kit, a couple servos and lipo batteries and stuck this glider together with some shoe glue and hot glue. Made hinges out of vinyl notebook. I used shoe contact cement to glue in spars as it stays flexible but holds well and will not shatter when flexing or hit. I have doinked this glider on its nose many times and it just bounces. The spars in the fuse are definitely necessary and functional

Went together in about 3 hours. Didnt even cover the wing or fuse. Mounted the rx upside down to protect the wires and had to put some coins under the battery for counterweight.
Boy what a kick this glider is. I maidened it yesterday. Went to the football field here and after a couple of glide tests, sidearmed it up. Beautiful.
I can only throw it about 15 meters high but spent another hour today and I was sweated out and sore. What a thrill this flatland gliding thing is.
Don't know what it weighs but feels like nothing. 6 gram servos, no covering. Put single spars in top of wing and the balsa elevons are doing great.
Yesterday the grass was wet and the epp was soaking up the water so plane got heavier but still flew.
Did some catches which is surprisingly easy.

Always something new to learn in the rc world.