Speedy "Red Mini Wing" RC Plane
Made by jorgecam, uploaded
Description
More FPV videos:
crash (very bad lunch ...) https://youtu.be/DYQUXU0mu_4
gliding (yes, it can glide !!!) https://youtu.be/4Bjhz2II-3U
low passes at full speed https://youtu.be/99NEkFP-Bvo
UPDATE 07-2017 : Succesfull flight in first person with googles !!! see videos here:
https://youtu.be/Aeqm5MTrcMg
https://youtu.be/wV9ATEqjeGI
https://youtu.be/iV-kBd63h6w
Hardware from banggood;
UPDATE 07-2017 : After several flights I have to say that I really like this plane !!! I finally removed the winglets and keep the balsa extension to the vertical stabilizer seen in the picture. It greatly improved lateral stability. Next step : FPV ....
UPDATE 05-2017: It flies !!!! A maiden flight of 10 minutes, with some stability problems but probably because of gusty wind. Landing was not peaceful (see picture), so some reprint will be needed....
It´s done !!! Waiting for the weekend for the maiden flight ....
I finally installed a Cobra 2208-26 1550 kV motor, to reuse a set of 2S 1100 mAh batteries and a 12A ESC I already have. Total weight is 460 g, and CG is about 32 mm.
This configuration will develop less power than the original one (Turning 2632 with 3S battery), but with a 9x6.5 propeller it should give me, theoretically, about 550 g of thrust (I have measured 11.5 A peak at full throttle).
According to Cobra specifications, with this propeller full throttle should not be used all the time to avoid overheating (Measured temperature was 48º after 5 minutes at 80% throttle, but rises up to 60º at 100%).
With a 8x4.5 propeller there is no temperature restriction, but theoretic thrust goes down to 430 g. I have one, but I prefer to use the 9x6.5 in the first flight, just in case I need a power boost ....
Just a few adds-on (see pictures):
- Two pieces of fine grade sandpaper to avoid lateral movement of the wing.
- A 2 mm carbon rod reinforcement inside the fuselage, behind the motor. Deformation of this zone when laterally pressing the fuselage generated a crack. With the reinforcement it is more rigid.
Thanks Wersy for sharing this beautiful design (and for the advice on choosing the motor) !!!
Print Settings
Printer:
Legio (from Leon3D)
Rafts:
No
Supports:
No
Resolution:
0.18 mm
Infill:
0%
Notes:
Wings printed at 0.18mm layer height, and fuselage at 0.27 mm.
Printer is a Legio, from Leon3D.
Hi Jorge
Neat that you are using the mini wing for FPV.
Hello
Neat flying plane.
I damaged the first wing and flew it with tape wrapped over the holes in the leading edge. Can see the tape over holes in the leading edge of the left wing, at the launch of this video. https://youtu.be/ybawO-EKDr4 . Later reprinted the wing using 2, 220mm center sections for lighter wing loading. Landing has to be attempted pretty fast. I have had some wing slap in flight.
Heat is definitely a problem at the motor mount. Since the motor is enclosed and does not receive much air. Perhaps Michael would redesign a very slightly fatter (maybe 10mm) front fuselage starting at the motor area with some vent holes.
I used the slicer program to stretch out the vertical stabilizer. Felt like particularly with a bigger wing more drag at the back would be appropriate.
LIked your use of sand paper to help stabilize the wing mount.
Hi Dave, yes, it is a beautifull desing. I am very happy with it, lots of fun !!!
Hi Jorge,
Dave did fly already my new Midi Wing. It is a bigger version of the Mini Wing I haven't uploaded yet.
Are you interested?
Hi Michael, yes I am interested, I was actually thinking about building the swept-wing 2.
Hi Jorge,
It has a wing span of 1000 mm and wing chord 202 mm. It is for a 28 mm motor.
You can see it flying by Dave: https://www.youtube.com/watch?v=y8ECqxQFIFE&t=6s
I want to publish it if I have my own video but is not posible now.
If you want the files send me your mail address per PM.
Hopefully Wersy will make the 1 Meter Plank available on Thingaverse.
Here is something I wrote up:
https://www.rcgroups.com/forums/showthread.php?2905975-1-meter-flying-wing-Pic-and-Vid
Hi Jorge,
"arduino Dave" had also issues with instability. He scaled up the stabilizer, and increased also the wing span to 38" - and seems to be happy :-)
https://youtu.be/ybawO-EKDr4
https://youtu.be/mvnUKd89KLw
Maybe you could scale the stalilizer too, but only in z-direktion, so you will not change the hole distance on the base.
Michael
Hi Michael,
it sounds like a good idea. Perhaps I could cut a flat addon from a balsa panel (with the shape of an inverted "L", I mean) and glue it to the actual stabilizer, so I do not have to unmount it. What to you think?
jorge,
Hi Jorge,
I could try to design a part to glue on top, that means enlarging it in height.
Michael
Thks Michael, but look at the picture I uploaded. I think it could work at least for testing.
If you agree I can test it next weekend, and if we confirm the stability improvement, perhaps you can design the add-on part, or even a new bigger stabilizer. Don´t you think so?
jorge.
Hi Jorge,
This is a good idea. You could start with the entire enlargement and then reduce it by and by, to see how much is needed.
Do you glue the stabilizer onto the fuselage?
I just glue a wire in the 2 mm throughgoing carbon tube and bend it on the bottom side of the fuselage to fixiate it.
So I am able to easily exchange the stabilizer.
Edit:
And, if possible, start testing without winglets.
Michael
Hi Michael, after several flights I have to say that I really like this plane !!! Lot of fun ...
I finally removed the winglets and keep the big stabilizer balsa add-on. It was the best configuration.
Jorge
Hi Jorge,
I am happy with you. Thanks for your feedback.
Attention:
Don't risk to fly with CG at 32 mm. Then it is very likely, that you have to print a new one ;-)
Try to reach 27 mm, or at least 29 mm.
Overall weight is 460g. Are you sure?
Where did you saved the weight? My motor weights 58g, that is only 11g more than yours. The batteries should be almost the same, about 70g.
With wich width you printed the wings, less than 0.5mm?
If you reach enough power, your configuration looks really good.
GOOG LUCK!
Hi wersy, thanks for the advice on cg. It is measured from the wing attack border isn't it? I think the weight is correct, i will check tonight and confirm, and I will also weight the battery. I used 0.4 mm width for the wings.
Hi Jorge,
Yes, the CG is measured from the leading edge.
If you used 0.4 mm width, it is no wonder that your wing is much lighter.
It is OK if the upper surface keeps in shape - and does not start to flatter when flying.
Because if you print thinner as 0.5mm, the perimeter of the upper side will not merge with the perimeter of the inner spars.
You printed with 0.18 layer hight. How many bottom and top layer you used?
You must reach 0.6 mm solid for bottom and top. Otherwise the inner spars will not connect the top and the bottom layer. There will be a gap inbetween.
I like the colors you choose for the wing, it looks like a bumble bee.
Speedy "Bumble Bee".
And thank you for the label with "By Wersy" :-)
I confirm that total weight is 460g, and battery is 45g.
The center yellow sections of the wing and the black sections were printed with 0.4 and extrusion multiplier 1, and they are definetely weaker than the middle yellow sections and the orange alerons, for which I incremented the extruder multiplier to 1.2 (so they are probably around 0.5 mm width). I didn´t realize that width was set to 0.4, so I progesively incremented the extrusion multiplier during printing of sections.
Probably I should print a new strong wing with all sections at 0.5 mm, but I will try this first. The upper skin looks bonded to the spars, so I will take my chances ...
Yes, I used more bottom and top layers to compensate the reduced layer height.
I like the "Speedy Bumble Bee" name !!!! If it survives to his first flight tomorrow morning I will prepare a logo for the tail ...
Hi Jorge,
Hopefully you have a helper who launches the model. And maybe somebody to take a video.
Probably I am more excited than you...;-)
Success !!!!! (Almost .....)
First flight : Direct to the ground :-( .... I was alone, so I launched it by myself but with too little strength. Fuselage broke near the nose, but after some glue it was ready again in 10 minutes.
Second flight: I trimmed elevator up and launched it again but with more energy and more angle and ... IT FLYES !!!! Beautiful flight of almost 10 minutes ... Power plant is ok, at full throttle it climbs easily, and most of the flight was at 60-70% throttle.
It trended to go down, so I trimmed elevator a bit more up. Once on ground I measured 1 mm of elevator trim up.
I noticed some "tail" instability, I mean, small and random lateral movements side to side. There was some gusty wind, perhaps it was that.
Wersy, what do you think? CG is now 28 mm, should I reduce or increase it to compensate for the nose down trend? Perhaps the lateral instability could be improved also by moving the CG ?.
I was also thinking about the winglets. I printed them in 0.9 mm, perhaps some vibration that causes that behaviour? I can try removing them next time.
Third flight: Shorter, because wind increased suddenly. During landing, and like a good Bumbble Bee it is, he went out of the runway looking for flowers .... Result: hard landing against a bush and leading edge of the center section broken (see picture). I glued the sections together during assembly (bad idea) so repair will not be as easy as "reprint and replace", but it is not as serious.
So, I am very happy !!! Despite the hard landing, it was a nice morning flying this nice airplane, and for me, it was coming back to this hobby after 20 years ...
Thanks Wersy.
Congratulation!
I am very happy with you, and I hardly can believe, that you were able to fly it, after so long time you didn't fly. It is the most difficult model of all I designed. You are still a good pilot! I wished I could do it as well, I always need sombody to fly my models.
If you want to have it easier, not so fast and more relaxing, I would recommend my little Swept Wing. Furthermore, it has, as everybody say, excelent flight characteristics.
Currently, my aerodynamic specialist is on holiday, so now I can't say much about the tail instability you noticed. In general, the instability increases, the more the CG is backwards.
I just saw, that I have marked my CG at 27 mm. I remember that the elevator was also trimmed 1 mm upwards. It was allways flown without winglets. Maybe they bother more than they are helping, though "wytti" said, with winglets it flies like on rails.
You don't need to glue the wing sections. This is the great advantage of this design. Just cut threads ( carefully into the tube ends and screw the wing together. Even the Swept Wing needs no gluing, only through going cords which are fixed with luster terminals on the wing ends.
And yes, next time you should put some flowers on the runway before launching your Bumble Bee...
Well, I guess that flying is like riding a bike ... you never forget !!! ;-)
I will repair it and I think I will fly it a few more times with less wind before doing any change. It was not a very confortable weather today, and that could be the problem. I remember I had a small model, and they do not like wind very much...