Melusine - Twin tailed siren
Wingspan: 2320 mm
Length: 1290 mm (varies with length of nose cones and tail booms)
Weight: 2000-2400 g
The prototype weighs 2300 g as flown in the maiden video and has 200 g of nose weight due to using heavy 12x10 mm tail booms instead of 12x11 mm.
Control surface deflection:
Ailerons 12 mm down and 20 mm up.
Elevator: 20 mm up and down. 25% expo.
Balance: 70 mm from the root leading edge.
New front EDF housing added with more aggressive look. EDFhousing04.
I added a second EDF housing with a cooling hole to draw air out from the inside of the fuselage. Name EDFhousing03
Note: EDFhousing02 and EDFhousing03 have a support piece inside the motor mount area. Push this part out from the top through the motor cooling holes after printing. It's imperative that good cooling be used in this area.
I designed a 70 mm EDF for the glider. The EDF unit slots onto the back of the fuselage where the motor hatch used to be.
EDFhousing01 and EDFhousing02 should be glued together with 4 mm index pins (carbon rod or something else 4mm). EDFadapter01 is for the inside of the motor plate of the fuselage so that the mounting screws for the EDF unit have something to screw into. You can use countersunk screws to hold the adapter plate in place if it's not a tight enough fit to sit in place.
EDFimpeller01 is a printable 70 mm impeller. Experimental impeller, and only for people comfortable with printing props and impellers for use. Wear eye protection when running. Other aftermarket 70 mm impellers can be used. The EDF is made for 28 mm motors with a screw mounting pattern of 19 mm. I suggest 2300-2800kv motor capable of 50A for 4S.
Here's an alternative impeller for prop adapters. This one is proven to work: https://cults3d.com/en/3d-model/various/70mm-12-blade-edf-fan-fits-starmax-f-5-edf
I designed new wingtips, ailerons and V-tail control surfaces with feather shapes to mimic a bird. It complements the beak nose. The files are:
I added new wings with lighter internal structure. They save about 60-100 g. Print them with only two top and bottom layers for extra low weight. The file names are Wing01-light to Wing05-light
This bird now has a beak. An optional nose cone shaped like the beak of a bird of prey:
Also added servo covers that can be used to clean up the bottom of the wing. Servocover01 has room for 6,5mm servo arm protrusion while 02 has room for 11,5 mm servo arm protrusion from the wing surface.
I added inner wing parts with flaps. Use 2 mm carbon rod as the hinge, and a 9 g servo for each flap. The new parts are Flap01, and Flapwingroot01. Fuselage01 and Wingroot02 have tiny holes added for the flap hinge rod to go through.
I added a V-tail option. The parts are V-tail01 to 03. I have not had a chance to fly with it yet but it's available for download.
My first 3D printable airplane. It's a twin tail pusher prop electric glider with interchangeable noses for FPV cameras, and optional tricycle landing gear with a steerable nose wheel. It also has 3D printable folding props.
I don't recommend it for beginners because it's too fast.
Stay under 600 W with the printed propellers. Stay out of the line of the prop disc and be careful with them. If you don't know what you're doing, you can always buy some props to be safe. 45 mm diameter spinner will fit.
Required hardware. The links are my affiliate links, which helps me fund future designs, but cost no extra for you:
-Assorted M3x12 to M3x30 screws and m3x5 and M3x12 grub screws. M4x30 mm screws for the main landing gear. Also neded are assorted M3 nuts with and without nyloc.
-Two 12x11x1000mm carbon tubes for the tail booms. Cut down to 770 mm
Alternatively 12x10 mm tubes can be used, but this will require about 200 g of nose weight to counter the extra weight. 12x11 is highly recommended.
-One 10x8x500 mm carbon fiber tube for the wing center section. Cut down to 440 mm
-One 8x6x1000 mm carbon fiber tube for the outer wing panels. Cut into two equal length pieces
-Three pieces of 2mm round carbon fiber rod for the elevator, horizontal stabilizer, ailerons and elevator pushrod.
-Adjustable pushrod connectors for the elevator pushrod
-Pushrods for the ailerons
-One 44x10 mm nose wheel if you don't want to print.
-Two 60 mm main wheels if you don't want to print them.
-4x 9g servos for the control surfaces and nose wheel
-Servo extensions. 2x 15 cm and four 60 cm
-600-700 kv motor with 5mm shaft and less than 39mm diameter. Mounting screws 25 or 19 mm apart
The prototype flies with a Hyperion Z3025-12 665kv outrunner.
-A larger outrunner can be mounted to the outside of the plane. a 45 mm motor will be the same diameter as the fuselage. Suggested motor:
-The plane can also be flown using a brushed 540 or 550 size motor.
-Suitable ESC with BEC
-3S to 4S lipo weighing at least 400 g for balance
Use your maker skillz and airplane experience to assemble parts that aren't mentioned specifically here. ;) Or let me know what's unclear in the comments below.
Wing parts should be glued together end to end with CA. 20-30 mm lengths of 2 mm carbon rod can be used in the rectangular slot on each wing joint to strengthen the joint for extra impact resistance. I recommend using thich ca in a couple of spots first to tack it together, and then apply thin CA to the joint when it's tacked together in the right place. Sand the joint while the CA is still wet to fill the joint with PLA dust. End to end CA glue joints like these are incredibly strong. Each wing half should have one 8x6mm diameter and 500 mm long carbon tube glued in to act as joiner with the center section. Also use 4mm carbon fiber as alignment pins in the root end of the long wing panels. Ailerons should be glued together with CA and a 2mm carbon should be used as a hinge pin. The wingtips can be glued onto the wings when the ailerons are in place. Take care not to glue the hinge pins so that the ailerons can't move.
The two wing root parts on each side of the fuselage should be glued together, but do not need to be glued to the fuselage. I recommend not glueing so that the fuselage can be replaced if it's damaged. They will hold together with the center 10x8 mm diameter and 440 mm long carbon tube which will work as a wing joiner tube with the outer wing panels. On the prototype I drilled 2,5 mm and threaded holes through the wing tubes, where you see a hole on the top of Wingroot02, when the wings were installed and use M3x12 grub screws to hold the wings on. This compromises the carbon spars a little, but it should be fine. An alternative way to hold the win panels on is to use tape around the joint. This is common with sailplanes.
Fuselage parts should be glued together with CA of your choice, and will self align due to overlapping joints. The nose cone of your choice should be installed with M4 screws.The battery hatch should be assembled with three M3 screws and will click in place on the fuselage by pressing forward and down on the rear end. The motor hatch will also click in place by pushing forward while pressing the rear end down.
The three horizontal stabilizer parts should be glued together with CA, and have a 2 mm carbon fiber rod in the leading edge for added strength. I do not recommend glueing this rod in place if you intend to fly in the winter, because it will cause the stabilizer to warp with large temperature changes. Use M3 nuts and M3 coutnersunk screws to assemble the horizontal and vertical stabilizers. The elevator should be assembled with CA and a 2 mm carbon rod should be used as a hinge pin. The carbon hinge pin should only be glued in one side of the elevator, or the elevator will warp with temperature changes because PLA shrinks when it's cold and expands when it's hot, while carbon fiber rods do not.
The vertical stabilizers are one piece and only need two m3 grub screws to secure them to the 12x11 mm diameter and 770 mm length carbon fiber tail tubes. Ideally they should also be glued in place, but I prefer to use grub screws in case something breaks. Glue the 12x11x770 mm tail carbon fiber tubes into the wing center section parts with CA.
The elevator control pushrod should be made from a 2mm carbon rod and uses the parts "Rodsupport01" as guides inside the tail carbon tube at 160 mm intervals along the rod. This ensures slop free and lightweight control. Use Rodsupport02 if you plan on using 12x10 mm tail tubes instead of the recommended 12x11 mm tubes. The elevator servo should be installed into one of the root wing sides as shown in the pitcure called "Elevatorlinkage01".
The folding props fit 5mm motor shafts and need two M3x12 grub screws to secure them to the shaft after the two tension plates have been inserted. The spinner might need some filing to fit the plates. The shaft needs to have a flat spot. Use two M2x30 mm screws and nyloc nuts to hold the blades between the two tension plates. The blades should be able to flap freely without slop.
Prop03 is ~13,3x8" blades. Suitable for 2-3S.
Prop04 is ~11,3x8" blades. Suitable for 3S.
Prop05 is ~9,8x8" blades. This is the one I use with 4S on the prototype.
Prop06 is ~8x6" blades.
The nose gear uses a spring for suspension. A hole has to be drilled in the leading edge of LandinggearNose01 to fit your spring. It assembles using M3 screws and grub screws, and a 4mm rod for the steering hinge.It uses the same type of 9g servo as the control surfaces for steering.
LandinggearNose06 and 07 are optional noses without pan servo mounts.
LandinggearNose08 is for a 32-33 mm long pan servo.
LandinggearNose09 is for a 28-29 mm long pan servo.
LandinggearNose10 is for a 22-24 mm long pan servo.
LandinggearNose10 is for mounting a camera with a 1/4" UNC thread on the bottom.
Wheelmain01 is one half of the wheel hub. Print two for each main wheel.
Wheelmain02 is the tire. Print from flexible filament.
Wheelnose01 is one half of the wheel hub. Print two.
Wheelnose02 is the tire. Print from flexible filament.
Print from PLA. Print parts in the orientation they open.
All wing files, control surfaces and horizontal stabilizer should be printed at 0,2 mm layer height with 0% infill, one 0,4 mm perimeter and three bottom and top layers. They also need a solid infill every 300 layers, which will work as a lightweight former every 60 mm and ensure the internal structure is bound to the skin.
The vertical stabilizers should be printed at 0,2 layer height, one 0,4 mm perimeter and 5% infill.
Fuselage files should be printed 0,2 mm layer with two perimeters and 20% infill in order to handle the load landings, and weight of a battery in the nose.