May 25 2011
Gord and I have done combat with these, and they work great. He won the first round a few days ago, and I ended up replacing the cowl ring around the prop with a two-layer laminated ring to give it more strength, which I should have done in the first place. I had run out of replacement props (8×4 DD), but I had one that had been modified by trimming 1/2 inch off each tip to make a 7x4DD. The smaller prop works just as well, and I can still hover with it.
This plane is maneuverable, and it can fly fast or slow, and roll into any position without losing lift or altitude. I’m having fun flying it. If I wasn’t, it would be gone by now (foam is cheap.)
Gord and I did combat again last evening, and I happened to win this round (sorry Gord.)
Gord brought one of these things out to the field a while ago. It’s different, and I thought it was cool so I built one too. This was a TLAR (That Looks About Right) project, designed as it was built. I gave it the same wing area as the Animal-X so I could use use the same hardware and be confident that the plane would be able to perform and have lots of power for 3-D maneuvers. FlyingBall-Tiled>
This plane flies well in any orientation. I gave it a crazy paint scheme on purpose so onlookers wouldn’t have any real clue about which part is the top of the plane. I like to fly it at a 45 degree angle, or knife edge, or inverted, or spin it like a top, just to help confuse things. I painted the top rudderon yellow to mark the top of the plane. It’s easy to see in flight so I can stay oriented.
The all-up weight is 6.5 ounces. The hardware I used includes:
- 2204/14 brushless motor and 8×4 GWS DD prop.
- 10 amp (generic) speed controller.
- (generic) Spektrum 6 channel Rx.
- (4) 5 gram servos.
- All up weight is 6.5 ounces.
- C of G is approximately 5.25 inches.
- Krylon Short-Cuts (paint) from Michaels, and masking tape.
I had built a motor stand some time ago and used it to test some motors and props that I had. The DD propellers turned out to be the the most efficient.
The motor is mounted as a pusher. The foam ring around the prop is 2 inches wide, and 10 inches in diameter.
This plane is built from EPP foam, which is quite soft, so it needs to be reinforced with a carbon fiber tensioning rod. The purpose of the rod is to stretch the foam taught (like a kite) to help it maintain it’s shape.
Glue the ends of the carbon fiber rod to the foam, and let it stretch the foam a bit. Then, very carefully add hot glue along the outside of the rod to help hold it in place. When finished, the foam should be taught like a drum, and flat.
I was going to use a tensioning rod on the vertical profile, but after I had put some test flights on it I decided that it wasn’t necessary.
Transmitter Programming
This plane has four control surfaces. The horizontal control surfaces are configured as elevons. The rudder consists of two control surfaces, an upper and lower. Each control surface has its own servo and receiver channel.
- Configure the horizontal control surfaces as elevons. In the Spektrum transmitter, this is done by selecting the delta wing configuration. Connect the left surface to the aileron channel and the right surface to the elevator channel.
- The upper rudder servo is connected to the rudder channel on the receiver and is configured as a standard rudder.
- The lower rudder servo is connected to the 6th channel of the receiver (aux2). In the transmitter, this channel is referred to as ‘flaps’ (go figure).
- Custom Mix 1: Rudder to Flaps, always on. Set the proportions to 100% in each direction. The upper and lower rudder surfaces should move together in response to the rudder stick on the transmitter. Trm: Enable will allow both surfaces to be adjusted as one large rudder surface using the rudder trim.
- Custom Mix 2: Aileron to Rudder, always on. Set the proportions to 100% in each direction. The upper rudder should move in response to the aileron stick to help roll the plane.
- Custom Mix 3: Aileron to Flaps, always on. Set the proportions to 100% in each direction. The lower rudder should move in response to the aileron stick to help roll the plane.
When the programming is complete the horizontal control surfaces should act as elevons. The vertical control surfaces should act as rudderons (rudder + ailerons). When the ailerons are used, all 4 control surfaces should move.
2011-June-20
Poor little fella bit the dust yesterday. We were flying combat when it suddenly decided to commit suicide. The servos I was using wouldn’t stay in trim and kept drifting, and I wasn’t able to maintain control. Crunch.
2011-June-23
The new ‘Fun Ball’ is ready to go. I used heavier EPP foam, so now the all up weight is 8 ounces. 1.5 ounces heavier than the previous one, but it should hold it’s shape better and be a little more difficult to damage. I replaced the funky servos with Hextronik 9g servos from a dead helicopter I had.
