Rhaps
Elite member
Last update 2024-09-02: Started the thread, Plans and instructions coming later
Rhaps Ultimate Biplane 780mm v1.0
Fun 3D/Sport plane. Very convenient size.
Not a beginner plane or build, maybe an intermediate one.
Gyro is strongly recommended as this has no self righting features. However even withot gyro the plane is totally flyable and quite fun but it is not very stable - you have to fly it all the time. With gyro it becomes lot more more relaxed and also takes bad weather surprisingly well.
It is surprisingly tough little critter. Especially with carbon spars on the lower wing I can do cartwheel landings all day (figuratively speaking).
Wings are KFM-4 wings and the motor is attached with velcro (no, really!)
Specs :
Wingspan: 780 mm
Weight: 550 - 650 g dry
Engine: C-pack radial
Prop: 10x4.5
Esc: 35A
Battery: Recommended 1300 mah 3s, altho 2200 works too (just less sporty). 4s should work too but I havent tried it yet.
Required materials:
(Note: This is just the stuff I have used, you just use what you have):
FT C-pack motor, esc (35A) , and Prop (10x4.5)
X-mount for motor (You can do without it but then you need to do a firewall from plywood)
Screws for motor mount (I like M3 screws a lot, they are more reliable than wood screws).
4 x 9 gram servos
Strongly recommended: Gyro
4 sheets of foamboard
Popsickle sticks
Popsickle sticks of longer and thinner variant
Barbecue sticks
Recommended: 80 cm X 5mm carbon tube
Cardboard
Optional: Soda bottle and plastic sushi box lids for a clear canopy.
Optional: Table tennis ball as a pilot
Zipties
50 cm (19.7") of 2.5 mm(1") stainless steel rod for landing gear (same stuff that comes with Simple Scout and Cub SBK)
Some 1.5 mm music wire for tail skid and tail pushrods
Some 1 mm music wire for aileron pushrod (the FT stuff)
Dubro 63.5 mm (2.5") x 10 mm wheels
About glue
You can use just hot glue for everything but lately Ive been veering away from it as Ive noticed that the planes done with other glues tend to last longer. It is also bit messy. Also for gluing foamboard surfaces it seems to be less than ideal as you dont have much time to align the pieces correctly. For fast building hot glue is still the best.
Here are the hot glue alternatives I've used.
PU-Glue: Excellent for gluing surfaces to gether, altho you need a bit of patience to wait it to cure. You can also make poor man's PU Foam from it, just ad water (you can do it over the glue if needed).
Wood glue: Nice to work with as it is water soluble before curing. Needs a lot of patience though and also you need to compress pieces together. It is excellent for wrapping the paper around foam edges (use very thin layer of glue.
UHU Por: For the places you need to have compress and you don't want to use hot glue: Lay glue on both sides, wait for 15 minutes and press the pieces togther and glue will stick immediately.
You can spot weld the pieces together with hot glue while you wait PU Glue or wood glue to cure.
Also I have used paper napkins to spread PU and Wood glue
About the build:
In general I'm very happy with the build but unfortunately I probably don't have god given wisdon to know the absolutely best solutions. So if you feel that you can do some part better let us know in the thread. Also if the build instructions are unlcear or otherwise lacking let me know about that too.
Aanyways.. here are some highlights from the build
Rhaps Ultimate Biplane 780mm v1.0
Fun 3D/Sport plane. Very convenient size.
Not a beginner plane or build, maybe an intermediate one.
Gyro is strongly recommended as this has no self righting features. However even withot gyro the plane is totally flyable and quite fun but it is not very stable - you have to fly it all the time. With gyro it becomes lot more more relaxed and also takes bad weather surprisingly well.
It is surprisingly tough little critter. Especially with carbon spars on the lower wing I can do cartwheel landings all day (figuratively speaking).
Wings are KFM-4 wings and the motor is attached with velcro (no, really!)
Specs :
Wingspan: 780 mm
Weight: 550 - 650 g dry
Engine: C-pack radial
Prop: 10x4.5
Esc: 35A
Battery: Recommended 1300 mah 3s, altho 2200 works too (just less sporty). 4s should work too but I havent tried it yet.
Required materials:
(Note: This is just the stuff I have used, you just use what you have):
FT C-pack motor, esc (35A) , and Prop (10x4.5)
X-mount for motor (You can do without it but then you need to do a firewall from plywood)
Screws for motor mount (I like M3 screws a lot, they are more reliable than wood screws).
4 x 9 gram servos
Strongly recommended: Gyro
4 sheets of foamboard
Popsickle sticks
Popsickle sticks of longer and thinner variant
Barbecue sticks
Recommended: 80 cm X 5mm carbon tube
Cardboard
Optional: Soda bottle and plastic sushi box lids for a clear canopy.
Optional: Table tennis ball as a pilot
Zipties
50 cm (19.7") of 2.5 mm(1") stainless steel rod for landing gear (same stuff that comes with Simple Scout and Cub SBK)
Some 1.5 mm music wire for tail skid and tail pushrods
Some 1 mm music wire for aileron pushrod (the FT stuff)
Dubro 63.5 mm (2.5") x 10 mm wheels
About glue
You can use just hot glue for everything but lately Ive been veering away from it as Ive noticed that the planes done with other glues tend to last longer. It is also bit messy. Also for gluing foamboard surfaces it seems to be less than ideal as you dont have much time to align the pieces correctly. For fast building hot glue is still the best.
Here are the hot glue alternatives I've used.
PU-Glue: Excellent for gluing surfaces to gether, altho you need a bit of patience to wait it to cure. You can also make poor man's PU Foam from it, just ad water (you can do it over the glue if needed).
Wood glue: Nice to work with as it is water soluble before curing. Needs a lot of patience though and also you need to compress pieces together. It is excellent for wrapping the paper around foam edges (use very thin layer of glue.
UHU Por: For the places you need to have compress and you don't want to use hot glue: Lay glue on both sides, wait for 15 minutes and press the pieces togther and glue will stick immediately.
You can spot weld the pieces together with hot glue while you wait PU Glue or wood glue to cure.
Also I have used paper napkins to spread PU and Wood glue
About the build:
In general I'm very happy with the build but unfortunately I probably don't have god given wisdon to know the absolutely best solutions. So if you feel that you can do some part better let us know in the thread. Also if the build instructions are unlcear or otherwise lacking let me know about that too.
Aanyways.. here are some highlights from the build
