Rekon 3 Nano - 1S 18650, not quite there yet
• Chris Landa
When I first saw the Rekon 3 Nano Long Range, I thought - awesome, a 1S 18650 RTF (Ready To Fly) micro quadcopter - I need to check that out! Banggood was kind enough to send me one over for review.
Designed by Dave_C and manufactured by RekonFPV the Rekon 3 Nano Long Range will have a very specific target audience, and in this post I want to take a closer look and help you decide if this might be something for you.
First of all, I want to address the elephant in the room - the price: With around 160$ for the PNP version this copter is on a quite pricey side for an analog micro 3”.
The RTF version with a Crossfire Receiver will run you a bit over 180$. But with the components used, I still think you get your moneys worth.
The copter weighs in at 65.4g with a Crossfire Nano receiver and 111.1g with an LG HG2 battery installed.
But why 18650?
18650 Lithium-Ion cells have a couple of benefits over LiPo batteries that we usually use in our hobby:
- lower energy to volume ratio - more capacity in a smaller form factor
- less sensitive to storage - just make sure you store the cells with more than 2.5V cell voltage and you will be fine. Optimally store them at 50% capacity in a cool place
- High availability: you can walk into your local vape shop and get a decent quality 18650 cell
Obviously there are also some cons needed to be mentioned:
- Metal case which adds additional weight
- Relatively low discharge currents: Where Lipo batteries can deliver discharge rates of 75C and more, the best 18650 cells max out at around 10C. The Sony VTC6 currently being one of the cells with the highest continuous discharge rate of 35A.
The main issue when it comes to 18650 cells and quadcopter is their relatively low current delivery. This is something that needs to be kept in mind when designing a quadcopter that will run off of 18650 cells.
Electronics
The AIO is an HGLRC ZEUS 5A board. It has an additional feature which allows you to adjust settings via WiFi, a feature that I don’t really care for but might be interesting for other people.
The ESCs are flashed with BlHeli_S P-H-90 firmware, it is important to note, that some users had problems with their ESCs popping after flashing Blheli_M. Personally I am a bit hesitant to flash Bluejay myself. The flight-controller gets pretty hot - hotter than I am comfortable with: during flight the core temperature increases to 95°!
The VTX is a Zeus Nano and is powered from the flight-controllers 5V line. The video transmitter is switchable between 25, 100, 200 and 350mW and comes with a linear brass antenna. The transmitter does have an IPEX connector, so you can run any antenna of your choice
Dave_C’s original design had a step up converter and LC filter from which the video transmitter is powered, this is not the case with the Rakon though.
The camera used is a Caddx Ant and I probably do not need to mentioned it at this point anymore, but mine came pre-installed with dust on the sensor. I now really think that Caddx is doing this just to personally annoy me.
HGLRC Zeus 5A AIO getting too hot
As mentioned before, this AIO is getting super hot. I have heard from a couple of people that after flashing JESC or BlHeli_M their FETs popped, this made me very cautious when attempting to flash Bluejay.
After establishing a temperature baseline, I chose P-H-120 instead - a firmware with a higher dead-time - instead of P-H-90 which came flashed per default. This change lead to the AIO running significantly cooler: the core temperature would stay well over 10 degrees cooler than with the stock firmware.
Receiver Options
The Rekon can be bought with different receiver options:
- Crossfire Nano
- FrSky R-XSR
- FrSky XM+
- Flysky
Alternatively you can get a Plug and Play version and run any receiver of your choice. The receiver is also powered from the AIO board directly and is also powered when the flight controller is plugged in via USB. When choosing a version with receiver, the receiver is already pre-installed.
The one I got came with a Crossfire Nano.
Motors and Props
The Motors are Rekon branded 1202.5, 11600KV motors, they are super smooth and have a 1.5mm shaft. The included props are 3” Gemfan Huricane 3018 Bi-Blade props. Technically you can run any other 3” prop with T-Hub style mount, but you need to make sure to keep current draw in mind. A complete spare set of props is included.
This motor prop combination draws less than 15A in flight - this is something you need to keep in mind when choosing prop and battery combination, which we will discuss in the next section.
Battery Options
The Rekon 3 Nano long range runs on 18650 cells, and you need good cells. I cannot stress this enough: You need high capacity, high discharge cells or you will have a bad experience. My recommendation would be to go with a Sony VTC6, the highest capacity, highest discharge 18650 cell currently available.
Get your 18650 cells from a reputable vendor. Don’t order them off of Wish - you will most likely get a fake. If a cell is too cheap, you will get a knock off. Don’t try to save on 18650 cells or you are risking to lose your copter.
| Name | Capacity | Discharge |
|---|---|---|
| Sony VTC6 | 3200mAh | 35A |
| LG HG2 | 3000mAh | 20A |
| Sony VTC5A | 1600mAh | 35A |
Flight times
According to the manufacturer you can expect a flight time of 15 minutes on a VTC6 cell. With the LG HG2 I fly for a bit over 10 minutes of faster cruising. 15 minutes with the VTC6 is realistic if you are just slowly cruising around.
Frame
The frame is really something different. Since the battery is mounted on top and simply pops into an off the shelf 18650 battery holder, the electronics are mounted on the bottom of the quadcopter.
The cover protecting the electronics is made from injection molded plastic - this seems to have been improved, since I have seen other reviewers complain about it being 3D printed.
What is still 3D printed, is the top plate of the copter, to which the cam is mounted to, and this is in my opinion the biggest weakness of the copter. I had a very light crash with my second battery - maybe dropped from 30cm height - and the main plate of the frame broke at the height of the battery tray.
Luckily you can find all the 3D printed parts on thingiverse, but it is really unfortunate that it is so fragile. Also you should print those parts from PETG to have some rigidity. I improved on the original design and reinforced the top plate a bit where the cam mount meets the base.
The arms are cut from carbon and are sandwiched between battery holder, main plate and cover.
Software
The Rekon FPV Nano 3 Long range comes pre flashed with Betaflight 4.2.0 and the settings are actually pretty decent. For my first flights I only set up modes and adjusted the OSD to my liking. You can download the original dump here.
What I then personally changed on mine was:
- enable DSHOT Beacon - this will save you some time when searching for your copter. There were a couple of occasions where I got a bit too excited and attempted a flip or roll at the end of the battery from which I could not properly recover, resulting in it getting lost in deep grass.
To try out my modified configuration, you can download it here.
Flight Characteristics
As mentioned before, the default tune is pretty decent, not much to complain about there. I even used the default rates and did not plug in my freestyle rates. The copter is quite susceptible to wind, if it is a light breeze, the copter will handle it, but you will definitely notice some shaking in the image and you will have to fight against the wind.
As soon as the wind gets stronger, things get really bad and you are getting pushed around quite a bit and it is really hard to push against it - pretty comparable to a 1S whoop in my opinion.
Can I freestyle it?
The Rekon Nano 3 is definitely not made for freestyling. Although you can obviously make flips and rolls, it is just too heavy for me to consider it anything as being capable of freestyling, and it is also not what it is trying to be.
Check out my video to get a feel for how the Rekon 3 nano flies and why you should always use a high quality, 18650 cell.
Conclusion - who is this for?
If you want to be on the forefront of what will be the next hype, then this is definitely for you. You should be very confident in flying, since crashing will - with a very high chance - result in rebuilding the quad, so it’ll be best if you have a 3D printer.
You can pretty much not hear this copter from 15m away, which actually makes it the perfect park flyer and explorer. I can see me using it for scouting out a spot, before ripping it with one of my dedicated freestyle rigs.
The price point of $160 for the PNP version is pretty steep, and will put off a lot of people, even though I think you get your money worth’s of components.
There is definitely something very satisfying about being able to just pop a battery in and fly this thing for over 10 minutes and I had more fun with it than I would have anticipated - I was not sure, if “just” cruising around would be the right thing for me, but it is actually pretty relaxing being able to explore a larger area.
Unfortunately I cannot recommend this copter to the general public, it is a great attempt to try something different and it has a lot of potential, I just don’t think it is there yet.
What should I get instead?
A short time ago I saw a build made by Jye - one of the ELRS devs - running on a 18650 cell for 24 minutes. with pretty standard components and a rather rigid frame. I am sure happymodel will pick this up at some point and it will be a better choice than the Rekon Nano 3 Long Range.
So my recommendation would be, to give it some more time before getting an RTF or build your own.
Chris is a Vienna based software developer. In his spare time he enjoys reviewing tech gear, ripping quads of all sizes and making stuff.
Learn more about Chris, the gear he uses and follow him on social media: