GEPRC MX3 Sparrow

By the_AdimalFPV on May 01, 2020

5  876  2

Goal: To make a powerful 3" build with great punch that can film in HD. This build is updated as of May 1st 2020.
Total weight without HD camera: 244g
Total weight with HD camera: 300g

This is the build that I have used for the last 3 years. This was my first drone build, and although the soldering job was not pretty, it has held up over the years. Overall, this build has been incredibly durable, agile, and fun to fly. There may be some better parts for a 3" build today, but this build still flies very well. I would still recommend every component of this build for anyone thinking about building a 3" today. I will link my YouTube page below where every video on my page was created using this exact build.


------------- Filmed with Runcam 5 - Filmed with Runcam 3

These are some things I enjoy about this build:
Power -
Without an HD camera, this quad is a BEAST. The handling on sharp turns is superb. My punch outs are probably going around 70-80mph, and I am able to cross the length of a football field in around 2.76 seconds. The only issues I experience in handling occur during a freefall when I catch myself right before hitting the ground, but that is not very surprising being only a 3".

Flight Time-
No HD - Easily 4 minutes ripping balls - Around 5 - 7 minutes cruising
HD on - 2:30 ripping balls - Around 3:30 - 4 minutes cruising

Flying a 3" is pretty cool. There are a lot of tight gaps you can squeeze through that other sized quads simply cannot hit. The small size makes it look like a toy drone from Wal-Mart and when people watch it take off for the first time they immediately learn that this drone is not a joke. This thing screams like a banshee and when you fly past yourself, you will quickly be reminded of that is it not a toy.

I have crashed. A lot. Sometimes very hard. The only time I've had a part break was when I flew into a metal lacrosse goal going around 60mph. As you can see in the pictures below, this completely ripped off an arm from my frame. This frame has taken a lot of abuse and I would highly recommend it.

These are some things I regret about this build:
HD performance -
If you are looking to build a 3" that can film in high quality HD, then go build something bigger. I built this drone with the idea that I wanted something to fly with some real punch power, but would also act as stepping stone towards flying something like a 5". I succeeded in this goal, but the quality of my HD footage suffered because of this. Simply put, a 3" drone does not have the same stability a 5" has and it is especially evident on windy days. This paired with the weight of a real HD camera can cut back your punch power by quite a lot. While I can still manage 60-65mph punch outs, it does not compare to the stability and power of a 5" mini quad. I avoided a Runcam Split because I was uncertain whether I could fit into the build at the time, but with the new models out today it would be a good alternative that would not weight the build down as much.

Technical issues with the build:
Flight controller - During a crash where I broke the whole arm off the frame, the motor ripped a soldering pad off one of the 4in1 ESCs. I was able to solder the motor wire onto the other side of the ESC. The soldering pads for the battery lead are also incredibly small making it tough to fit an XT60 plug onto the board.u

HD Camera - When I build this quad, the lightest weight 1080p@60 HD camera on the market was the Runcam 3. I went through two of them and they both failed due to internal issues with the control board. They are incredibly unreliable and break easily. I am currently using the successor to this camera the Runcam 5 (Not orange) to keep the weight down. Currently, this camera has not had any issues, but I do not fully trust Runcam's HD cameras to last very long. This brings up another good reason as to why opting to build a 5" is better for quality HD perforamcne because a 5" can handle the weight of something heavier, like a Gopro.




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ChiefCleef   Nov 12, 2017  

Clowns make the best companions on steamy wednesdays.

the_AdimalFPV   May 01, 2020 


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