This is a mini quadcopter that I built a while back. I tried to build a frame myself using polystyrene and fibre glass rods, but it didn’t work as good as I expected. Later I replace it with a Hobbyking Micro quadcopter frame, which made a huge difference in stability. After some PID fine tuning in the KK2.0 flight controller, it flies really well. I will attempt to rebuild the frame using more rigid material, and use my own made Arduino flight controller with Multiwii 2.2 loaded. I recently built a upgrade version of the mini quad, check it out. Finally received all the parts from Hobbyking which took almost a month!. I guess they must be getting so many orders in their International warehouse because they usually have most items in stock (since it’s in Hongkong and right next to mainland China), and it would take them so long to dispatch orders. I live in the UK, and ordering from their UK warehouse usually is much quicker (dispatch within 1 or 2 days). So try to avoid ordering from their international warehouse whenever is possible.
Anyway Hobbyking is a great online shope because their products are so cheap and I should not complain really. Micro Quadcopter Components List I used: I first assemble and solder all the parts. Soldering the 2mm connector to the ESCs and brushless motors is much simpler than I first thought. You first heat up the connector with the solder iron, fill 70% up the hole with solder and put the cable into the hole. Remove solder iron from it and hold the cable in place until it’s firmly sticked to the connector as the solder cools down. And then put the head sinks on the solder joints. I was a little confuse about the wire connections of the ESC to the motors as they are all the same color. It doesn’t matter which wire connects to which. Because the motors are 3 phase device, by swapping two of them could reverse the direction of the rotation. So just wire them up randomly and see which way it turns, swap two of them if it’s turning the wrong way. The fibreglass is a spare part from the 949 beetle mini quadcopter, and the motor mount pieces are cut from styrene sheets.
To be honest Styrene are too soft to be used for motor mount as motors tend to generate a lot of vibration. More rigid material should be used such as wood or metal, or thinker harder plastic. The whole frame weights about 50g. I should remove the landing gear to reduce weight, since mini quadcopter can land and take off from the pilot’s hand anyway. Here is a failed flight video: This Fiberglass Micro Quadcopter Frame is from Hobbyking. Although it’s a little heavy and expensive, the rigidity is very good and not easy to break. But I would insist if you have a little spare time and patience, try and make a frame yourself as for mini quadcopter, light weight is important! And that’s what I am going to do. Also on these frames the motor holder has only got 3 holes, i think that’s some turnigy motors. It’s doesn’t fit the 2000KV 10g motors I am going to use unless using some sort of motor mount adapter, which is going to add more weight to the build. The whole thing weights 275g (including battery), which too much for a micro quad.
Although it flies, flight time is not very good. For 950mah battery it only lasts about 6 to 7 minutes. I use a knife to make 2 holes on the quadcopter arm, which does the job nicely. Here is two successful flight videos: I should try the 6030 or 6045 prop to get more thrust for these motors when using 2S. There are people using 3S battery on the 2000kv 10g outrunners motors to get more thrust out of them, but I don’t want to risk it. Also I can reduce more weight on the frame.:-) it should be able to carry a key chain camera FPV system. use prop adapters, the original prop savers that came with the motors generate a lot vibration I found. Maybe it’s the size of the prop savers are too big and not tight enough to hold the prop in place. This time I will make sure the places where the motors are mounted are very rigid, and use as little material as possible to reduce weight. I used 3mm fibre glass rod as the bone of the frame. These rod look much larger that i thought they would be, and because they are solid they are quite heavy.
I could have used 2mm rods, or even better, 3mm or 4mm fibre glass tubes (which is hollow and lighter). Materials are put together using hot glue. Hot glue isn’t a very good material either, because they are quite soft and doesn’t hold very strong. I learnt from my friend that you can use some kind of string/wire to tie the material together first if possible, then apply the hot glue to protect the string and cover the gaps. The DIY frame is about half of the weight of the HK fibre glass frame. Here is a video showing the performance. I have been trying to improve the stability and flight endurance of this micro quadcopter. I have made these changes and it flies incredibly awesome. It weights less (about 170gram excl. Lipo) and the flight time is now around 15-17 mins with 1600mah battery (used to be around 9 mins with 950mah), and it hovers at 50% throttle (used to be 70%), which gives me more room for a light FPV system later on. I also tried using 3S Lipo with these 1811 motors as well, it flies very good, it can stay in the air at around 30% throttle, and it’s very agile.
For the first 3 mins, the motors gets warm, but after that, the motors and ESC gets very hot. Not that it’s too hot to touch, or like some people have been describing, it could get so hot it melts the soldering, but I don’t like taking the risk of damaging the ESCs or motors, so I might just stay with the 2S lipo. As a DIY indoor flying mini quad, I would say this is a very successful result. I have yet tested this quad outdoor, see how good it is against the wind. I don’t expect good performance because of the light weight. The next improvement could be using even stronger motors that can be coupled with the 3S lipo, such as the Turnigy 2211. I will leave it for now because I will be busy flying with this beautiful quad for a while ;-p I finally built a light weight FPV system on the mini quadcopter, which only weights 27 grams including the antenna. I have yet tested the range of this FPV system, but I have been flying this mini quadcopter indoor within 20 meters and the video quality seems very good.