I wanted something that would be able to lift cameras yet be
harmless and made of parts that are both cheap and easily available.
The end result matches all my expectations. It has a stable flight
yet can be controlled in gusts of wind. With a1000 mAh battery it
can stay in the air for 13 minutes. Below is a demo flight on a
I just took the motherboard of an Eachine H8 (alias JJRC
H8 Mini) and doubled the amount of motors. One quadcopter can
be bought for $13 and parts like a motor or a set of propellers cost
The motors are a little further away from each other, to reduce the
interferences between the propellers. In an original Eachine H8, the
motors shafts are 55 millimeters apart. Here they are 63 mm apart,
at the ends of balsa rods of 80 mm, 6 by 6 mm cross-section.
The motherboard doesn't know that they are two motors at each end
instead of one. The two motors are simply soldered in parallel; they
will receive the same power. The wires come from a thin USB cable.
Not every motherboard will be able to adapt itself to such a change.
This one motherboard could barely control a quadcopter with 120 mm
balsa rods. When I replaced it with a Hubsan X4 H107L
motherboard, it completely failed.
The motor wires also act as suspensions for the motherboard. I
learned that trick when my first Eachine H8 became unstable.
At first I failed to understand that the problem was caused by a
propeller blade that was slightly bend downwards. This caused
vibrations that disturbed the accelerometers on the motherboard.
Raising the motherboard so that it would only hold by the wires did
help a lot, because the vibrations were less transmitted to the
motherboard. Then finally I lightbulbed that I just had to bend the
blade back in place.
Don't use balsa wood. Maybe better build a structure with carbon
fiber rods or build a stronger balsa structure than I did. I do like
my structure but it breaks easily. I often have to repair it with
superglue (pour a lot on each side, wait till it sinks in, lightly
push the parts together, wait till the glue forms filaments when the
parts are pulled apart, breathe on the parts to activate the
polymerization, push the parts strongly together, they will hold in
seconds, then let cure ten minutes or so till the next flight). The
battery in the image below is a 500 mAh double capacity one for Hubsan
The motors are first tightly wrapped in common polyester sewing
thread, with a drop of superglue to hold down. Then both the flat
end of the balsa rod and the side of the motor get a big drop of UHU hart glue soaked in. A minute
later the parts are pushed together and the excess glue is shaved
away. Then the position of the motor is checked and enforced using a
ruler. The assembly is left to dry for a few hours then finally the
excess thread above the balsa rod is removed.
To do what with?
The video below may seem to be one more dull drone flight with a
cheap low resolution camera and a bad landing. But think again. Did
you ever see a drone video wherein the flying drone records the
surrounding sounds? I soldered away the microphone of the Y2000
camera and hung it 1 meter below the device, connected to the camera
through two 100 microns varnished copper wires. The sound emitted by
the propellers is so weak that it can barely be heard.
If you need a better camera, a Y3000 or a 808 #16
have higher resolutions yet about the same weight. Be careful: "808"
cameras are sold for $7 but they have a low resolution. To have a
high resolution it needs to be a "#16" one. Also do take into
account the type of lens. The narrow lens of a Y2000 or Y3000
camera sees the world through a keyhole while an 808 #16
with a 120° lens will yield a more open image.