Things I’ve learned over the past 10 months that I’d like to share…
If you’re designing & making your own quad/hex with parts from China (Ebay, gearbest, …); if you need 1, order 2. (Always order more then you need to avoid being grounded, maybe for weeks, after a failure/crash.)
A sure sign the motors need to be oiled is when the craft “wobbles” (side-to-side) as descending. No need for special $$$ oil for the motors. (3 drops of oil on each of the two bearing in every motor, every 5-8 flights.) I use simple 5-20w Mobil 1 synthetic (Extended life) car oil with about 10-15% Zmax oil additive mixed in. At first I used a toothpick dipped in the oil to apply. Then I found these on ebay that made things MUCH easier.
If you are using the “2212” motors or bigger… Pop for the more expensive 40A ESCs. I’ve had the 30A ESCs fail when zipping around at full-throttle , and causing a spectacular fall & crash.
If you are using the cheap 7-8$ “2212” motors, it is much less expensive (in the long run) to use at least the $15 “2216” motors. (They are more expensive… but last HUNDREDS of flight hours, and are much more powerful.)
Use the more expensive (about 3-4$ each) carbon fiber propellers. Not only do they give the craft a “crisp & accurate” flight feel (due to their stiffness), but I’ve never had one fail mid-air. (I’ve had 3 plastic props fail. Two failed “just because” and one due to a small bird sucked into the propwash.)
Never fall for the cheap NEO-M6N based GPS module. (Accuracy seems to be +/- 30-40 feet!) Always pop for the more expensive NEO-M8N based GPS module. (Stated accuracy is within 1 meter, but I’ve consistently seen 3 INCH accuracy.)
Never POWER Servos or LEDs off the flight controller or RC circuit. (Even if they say they can.) I’ve had too many power brown-outs that caused expensive crashes. I add an extra power circuit using the $0.58 ultra-mini (under ½ inch square) 3A variable BECs, adjusted to the voltage needed & then seal with shrink wrap. (If you’re worried about EM noise; shrink wrap, then wrap with aluminum foil and shrink wrap over the foil.)
(And this is just my opinion.) I’ve made expensive Quads & Hexs using the expensive folding carbon fiber bodies/frames. But by far, I enjoy and fly most, the simple $25 plastic hexcopter body/frame. (Using a side-pin APM 2.8, M8N GPS, 4S battery, with the 2216 motors, pushing 1055 carbon fiber propellers, with Strobon SE flashing 6 - 1 watt, LED nav lights.) The performance is jaw dropping, with always awesome comments from observers.
Most people believe that water (due to the open electronics) is the biggest enemy/concern when flying. But in reality, pure/distilled water does NOT conduct electricity. (I’ve flown my quad/hex into fog clouds and landed them dripping wet, with no problems.)
The biggest enemy of drones is dirt/dust & sand. Most motors (under $35 each) have “shielded” bearings, not “sealed” bearings. (And yes, “shielded” bearings do require lubrication.) The fine dust & sand particles find their way past the “shielding” into the bearings and cause premature bearing failure. (When bearings fail; they start with them being noisy… then if ignored they refuse to spin when armed, and then burn out the ESC.)
When I know I’ll be taking off/landing in a dusty or sandy area, I use a 5 foot square “moving pad” (cost me just $6) to take off and land on; to avoid as much dirt intake as possible.
10.Noticed that a lower “center of gravity” (COG) makes the craft much more stable. Have seen several videos where their batteries (normally at least 30% of the craft weight) is placed on the top. (This makes the COG higher than the propellers, making it a less stable craft.) I always place the battery inside the main body (on F450 & F550) frames. And under the main body on my carbon-fiber TL680 frames.
All solid points, however, oiling of motors will bring up a contentious debate among many. Most motors are sealed bearing/bushing, and thusly, oil would never really matter. Sunnysky does recommend 1 drop of oil every 100 flights, but I flew it quite a bit more with no issues.
If a craft is wobbling side to side on descent, that may also be VRS (vortex ring state, or ‘settling with power’). That can cause an unrecoverable descent.
About motor oiling. The motors I have are “SHIELDED”… Not “SEALED”… (There is a BIG difference.)
When you actually see the oil disappear into the bearing, often bubbling as it does; clearly the bearing is not “sealed”.
Then after oiling the motot bearings, there is nice stable-flat descent with no wobble, (in my mind) there’s no doubting the results.
( Although I fully expect some doubting my recommendations/observations. )
Can you post a link to the stroben nav lights?
Note that they are made in GB. And kinda expensive. But they run on 5V and can be wired (in parallel) to several 1 watt LEDs. (They say the optimum # of LEDs is 4. I have mine to six - 1 watt white leds, one under each of the hexcopter arms.)
NOTE… You can not - mix - LED colors, (different colors take different voltages/amps) on a single SE unit. And you have no control of the flashing frequency. ( Two quick flashes, every second.)
These are the LEDs I used. (Cool-White 1 watt).
There are other (bigger and heavier) flashing nav lights out there. I ordered one of these… But haven’t tried them yet.
But it does allow multiple color LEDs, you can set the flash frequency, and has includes two BECs on the board to make the right voltage.
With the nav lights, an accurate M8N GPS, and put one flight mode to RTL (Return To Launch)… It’s safe to fly late night.
The flashing (300 ft up) really gathers ALOT of attention at night.
I’ve seen many cars pull over as far as 2-3 blocks away thinking they were watching a UFO fly around.
Hi I was recently in China…at night there was some kind of copter flying that had flashing lights… it was
almost like fireworks. Is this something available or is it something that has to be built. i woudl like to get an inexpensive model of this if possible… I am not a builder, nor knowledgable about drones/copters.
What do you advise?
To my knowledge… No premade (buy-and-fly) packages. (And what’s the fun in that ???)
This is how I did it:
- Make/Buy a DJI F450. ($200-$300 kit/premade) or spend under $100 for the parts and make yourself.
- Learn to fly it… Be aware, this doesn’t come easy, YOU WILL CRASH… a bunch. (i.e. need extra parts.)
- Learn to wire & program microcontrollers. I prefer Arduino. At $2 each, they can’t be beat.
- Learn to wire & control WS2812 5050 RGB LED Lamp Panels with the Arduino.
- Build a frame to hold 12 of the above panels under the DJI F450.
- Perfect the APM flight “Autonomous” (Auto) flight mode, with low-voltage RTL and RTL fail safes. (To be safe flying in complete darkness.)
This is what I finished putting under my F450 drone. It casts shadows on the ground from 200’ up.
The last pattern in the video may be what you’re talking about.
Copied below some Ebay sources for the activities:
hello every body
I am making a quadcopter with DIY F450 frame and tmotor air pack
I use a 3s battery and pixhawk as a controller
is there any idea for tuning the gain(I mean true numbers which can be chosen for the gains)
thank yo so much