FeiJi's blog - RC Groups
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Posted by FeiJi | Jul 04, 2017 @ 08:16 PM | 1,685 Views
Interesting article about owl wings leading edge serrations and other characteristics that make for a quieter flight.

https://www.sciencedaily.com/release...0704093621.htm
Posted by FeiJi | May 27, 2017 @ 09:37 PM | 2,449 Views
Formerly I had just taped some green LEDs onto my wing and that worked ok but you could hear the increased drag as the plane flew by and it cut down on flight time so I decided to cut some forward facing slots and insert the LED strings into the BOTTOM of the wing. Here are a couple of photos. I cut the slot, then push the wing apart and insert the string into the slot and then used a little hot glue in few places and just spread it over the slot to give it a little more strength. The LED string is flush with the wing so no increased drag.
I have done both wings and ironed on some bi-directional tape over a few areas. Hope the tape sticks.
Currently am using two small 1s lipos to power the 3 volt strings but plan on buying some 12 volt strings for the future so can just run them off the main lipo.
This should be loads better than taping on the wing. Here is an awesome writeup by CrashTestHobby.com about how to do it.
http://www.crashtesthobby.com/night-...ed-lights.html

Also an acrylic painting I did of one of my students.

Update: flew last night on football field and flies great. No drag and very visible. Unfortunately one led battery was dead so flew with only one wing visible but still easy to fly. Now can fly with or without lights and no difference in fight characteristics.
Posted by FeiJi | May 13, 2017 @ 08:16 PM | 2,584 Views
Put couple of LED one meter strings on my wing. Wow, very bright at night and dawn (totally ruins night sight). Much better than EL wire. My LED strings were 3 volt which posed a problem as I had to power them separately from my ESC battery but I had two small 1s lipos that are light and power the strings just fine. I tried using the 6 volts off the receiver but it almost killed my ESC - drew too many amps. I suppose 6 volt LEDs might work but could still draw too many amps. Other alternative is to use 12 volt LEDS and use ESC battery - probably the lightest solution and better if having more than 2 meters of LEDs.

I put the leds face down on the EPP so that they light up the wing more. Need to tape down the wires I guess for less drag. Very little weight added to the wing.

I bought my LED one meter strings (3528) for 11 rmb each (about 2 bucks) which is a whole lot cheaper than US prices that I have seen. Was worth the try. Guess I will keep them on the wing for a while and do some dawn flights since I go out running on the football field at that time anyway before the students start arriving for their runs.

Have a strange problem in that when I solder connectors to the strings and plug in the battery, only the green lights work. The red and yellow just blink on briefly and then go out. Guess the plug causes a touch too much resistance for the current my batteries are supplying (450mah). Not s
ure how I will get around this problem except with larger current batteries. Would be nice to have some other colors on the wing.

Lighting Wing with LEDs (7 min 50 sec)

Posted by FeiJi | May 02, 2017 @ 07:42 AM | 3,103 Views
Mounted my Canon 350HS Elph on my baseball cap. Much better at taking night video than my micro camera.

Lighting Dawn Flite May (4 min 18 sec)


Here is longer version of dawn flight.
Lighting Dawn Flite May 2 (8 min 47 sec)
...Continue Reading
Posted by FeiJi | Apr 30, 2017 @ 08:31 PM | 3,411 Views
A snippet of an early morning flight. Camera barely picks up the el wire lighting on the wing. Need to try leds. Will also mount my Canon Elph on my hat and try that first.
Lighting Night Flight (1 min 19 sec)

Posted by FeiJi | Apr 07, 2017 @ 04:42 AM | 3,594 Views
Saw this strange looking helicopter. The rotors are synchronized to not hit each other. Try an rc version of this.
Kmax Start and Takeoff in Agassiz BC (2 min 28 sec)

Posted by FeiJi | Apr 06, 2017 @ 06:48 AM | 3,601 Views
Added 2.3mm El wire to my Lighting. Using 12v inverter that I spliced into the 3s lipo/ESC leads and just taped it all on until I see if I like this night flying stuff. Football field is partially lit at night anyway so visibility should not be a problem. Inverter has two El wire lines out. Cost 4 dollars for the inverter and the two color el wires (1.5 meters each). I am always bragging how cheap I get stuff but that is just because I am working in China as an ESL teacher and I buy stuff off taobao.com which is really cheap here including their shipping fees (usually less than two dollars).
Inverter and El wires total 55 grams.

I flew the Lighting with the el wire and it flies nice, no noticeable drag or adverse flight characteristics and lands without dragging the el wire on the ground. But it was dawn and too light to really see the el wire so will have to get out to the field at 5:00am next time.

Update April 15: flew it this morning in the dark - easy to see and as long as I kept it in the football field it was ok but I let it get outside and lost orientation and crashed - broke wire off motor and motor mount. First time I crashed this plane. I don't really enjoy it as all I see is the lights and I don't get the feeling of flight as I can't see the plane itself. Will repair, fly once to get a video and then probably stop doing it as it isn't much fun to me. Maybe if the whole plane was lit up with leds from the inside it would be different.

Update May 1: getting...Continue Reading
Posted by FeiJi | Apr 01, 2017 @ 11:29 PM | 3,367 Views
This wing is usually flown with 2s batteries but I want to put some el wire lighting on it so need to go to 3s and I also wanted to see if battery would fit in fuselage without having to modify it. Happy to say the 3s fit perfectly since I fly with the ESC mounted on the top of the fuse for cooling. Flies pretty fast with 3s for about 5 to 6 minutes full power. Plane is a little touchier but still easy to fly. Love flying this wing - haven't crashed it yet.

Clip binder is there to attract magnets in hatch door. Could have used more magnets and may do it but the clip was handy and it is entertaining, I smile whenever I see it. Still can remove ballast coin and probably will when I add the el wire which should weigh about 85 grams with inverter.

Lighting EPP WIng with 3S Lipo (5 min 57 sec)

Posted by FeiJi | Feb 07, 2017 @ 07:56 PM | 4,149 Views
Have never really tried 3d except for a little fun with a NutBall and this balsa plane is available here in China for about $35 including electrics except battery. The nice thing is all the planes I have now use 2s and this one does too so keeps cost down. I used to use 3s up to 2200 and my wings were big and fast but now only have a football field to fly on and 800mm WS is about all I can fly here. So will order one of these soon.
Posted by FeiJi | Feb 06, 2017 @ 07:36 AM | 4,232 Views
This wing had sat on the roof of a stadium for 4 months in rain and snow and finally was blown off and I discovered it under the snow on the football field. Guess it helped that I was the only one looking for it but surprised others had not found it. Electrics still worked except for one servo. Patched it up and it flies pretty good now. Dirty but functional. 260 grams, 5 inch prop, tiny little motor, 2s 900 mah lipo. Only available in China as far as I know.

Flying Lost Wing Again (4 min 3 sec)

Posted by FeiJi | Jan 31, 2017 @ 04:54 AM | 4,208 Views
I managed to land my EPP wing on our football (soccer) stadium awning in September 2016 - and there it sat for the last four months. I saw that the wind had finally blown the wing off the stadium yesterday but didn't see it anywhere and figured someone had found it and taken it home. Then today it decided to snow and I was walking around the football field and low and behold there it was on the edge of the field upside down and covered with snow. If it hadn't snowed someone would probably have seen it earlier. I was really happy though I figured it wasn't much good.
Took it home, plugged in a battery and everything except for one servo worked. Amazing. Then thought since the lipo isn't puffed I would try charging it. So checked voltage, zero volts. Charged it for 30 seconds as an NiMH to get a charge in there and then balance charged it. Looks ok.

When the weather clears up will replace the servo and try it out.
Was a total unexpected surprise. Been through many raining days and nights and two snowstorms and still works.

Update: flew it the next day. Flew around a few times, crashed it and the nose broke right off. Evidently the weather has made the EPP very brittle (the cold doesnt help either). Easily repaired but I have a scratchbuilt I will transfer the electrics to. Never liked how this wing flew anyway. Such is life.

Update: Ok, the scratchbuilt won't fly w/o a lot of work so repaired this wing, and took it out and it flies. Not great but I put two...Continue Reading
Posted by FeiJi | Jan 16, 2017 @ 11:05 PM | 4,148 Views
Not sure what you call this modification but I took an acrylic ruler to use as a wing and glued it to the fuselage of my EPP wing to act as a small biplane wing or rearward canard. I had read that someone did this (actually he glued a couple of short stubby wings on the sides of his fuselage in about the same position as mine) several years ago (cannot find the reference article now) and he explained how it kept the airflow attached to the main wing for longer or some such thing. All I can say for sure is that it effectively pushes the CG backward so I can use a heavier battery or motor and that it improves aerobatic performance, gliding and slow fight. Guess it is like flying with flaps on but not as draggy. As one viewer proposes: it gives more lift. I guess it could be a simple as that, more wing area = more lift.

Lighting EPP Plank with biwing modification (3 min 36 sec)

Posted by FeiJi | Dec 10, 2016 @ 02:51 AM | 4,419 Views
Here is a cool plane that is good for 10 hours in the air using fuel cell. Of course Musk says fuel cells are dumb.

HYWINGS hydrogen fuel cell UAV demonstrator, powered by HES (1 min 32 sec)

Posted by FeiJi | Dec 07, 2016 @ 11:39 PM | 4,047 Views
I started out in rc airplanes in 2011 or so and after becoming familiar with rc and servos I eventually got involved in building Arduino controlled robots. Here is my last project: a scratch built seven servo Arduino robot using standard size servos. Kind of fun project but spent too much time programming it.

Bipedal StriderBot: Robot Moves (4 min 25 sec)

Posted by FeiJi | Nov 16, 2016 @ 01:08 AM | 4,318 Views
This would make an neat looking model.
Posted by FeiJi | Oct 29, 2016 @ 04:40 AM | 4,958 Views
Finally got my WFLY WFT07 transmitter working with FMS flight simulator on my Windows 10 laptop. First I had to get FMS working with my laptop as it has no ports and the FMS software bombs when it can't find a port. So ran a couple of bat files (here: https://www.rcgroups.com/forums/showthread.php?t=374732 )
Then I downloaded this superneat program http://www.smartpropoplus.com/site/ that uses the soundcard of all things to communicate between the TX and FMS.
Then just connected the TX trainer socket to the soundcard with an appropriate cable and then go into the TX menu and turn off the RF (which turns on the trainer cable communication).
Wow, works great. And all the software is free. Love free.
Posted by FeiJi | Oct 17, 2016 @ 03:20 PM | 4,322 Views
Here is an article about cool software that allows sailplane to search for and find lift.
http://www.popsci.com/new-software-l...inds-for-hours
Posted by FeiJi | Oct 16, 2016 @ 09:25 PM | 4,785 Views
I was flying my epp wing when the propeller came off midflight and the wing just kept gliding and gliding. I think this would be a real thermal queen if I put folding propeller on it. Will try that.