This is an updated shopping list for the quads I’ve built for my 2018 flying season. It’s based on lessons learned during 2017, and I’ll be discussing the results and reasoning behind each part. Hopefully you’ll find this useful if you’re building a new quad or three and want to save some money.
Last year I built three low-rider quads based in QAV-210 frames from Amazon. While the original frame I used is no longer available. It used a one piece, 4mm carbon fiber plate and was quite sturdy. I built the frame as an extreme low rider (only 15mm between top and bottom plates). This made for an extremely tight built.
While that setup flew lovely, proved to be extremely maneuverable and was very durable, it really restricted my camera options to this tiny CMOS camera. While this camera was ok for flying on bright sunlight, more often than not it proved to be a challenge with less than perfect weather.
I made two variants based on 2300KV and 2633KV motors, which worked well enough. I put roughly 30 hours of flight on each motor with only one motor-related failure. I was pretty happy with them so there’s really no reason to change as long as the parts remain available.
As for my VTX, I chose a generic 200 mW push-button video transmitter similar to this one. Performance was great, but I wanted the ability to change frequency and power settings on the VTX via my OSD. SmartAudio was starting to come out and I figured I would upgrade when those transmitters died on me. They did not.
For my receivers, I went with the FrSky XSR. I did the 29mm antenna trimming mod on them and got slightly increased range. With full S.Port telemetry, good range and diversity, I thought I could not do better.
Goals for 2018 builds
As usual, I wanted my 2018 builds to be fun to fly, inexpensive and reliable. I don’t have a lot of time for building and repairing. While I can spare a couple hours per week for repairs and adjustments, I need my quads to remain in flying conditions with minimal care. I also don’t want to spend too much on them so as to keep me flying aggressively.
Having a 4mm main plate was a must, as this proved to hold up well to all sorts of crashes and most mid-flight encounters.
I was willing to allow myself some indulgences such as a better camera so that I could fly better in less than perfect weather and adjustable VTX power and channels, so that I could do adjustments quickly while my quad was away in the take off pad.
Since I had spare XSR receivers from last season and I had no complaints about them, I decided to keep using them.
On my ESCs, I decided to jump into the BlHeli32 bandwagon, so I would be getting powerful ESCs with this firmware supporting DSHOT600.
As for flight controllers, I would be going for an AIO F4 based board.
Given currently available technology, something had to give. I decided to do away with the low rider setup in order to equip a decent camera. So far I’m linking the results.
The jury is still out. For the first two quads I’ve gone with this frame. This frame uses a 4mm base plate while the top plate is light. The minimal configuration I use required only 8 screws.
The carbon fiber flight camera mount is a joke and you should not use it unless you like looking for your camera every time the mount ejects. This is not as big a drawback as it would seem. Turns out that the mount clamp that ships with the cameras I chose make a more than decent job.
There’s something to be said about the quality of the main carbon fiber plate though. In one of my frames, after hitting a gate, there was visible delamination on one of the arms. The impact wasn’t particularly hard, so I’m not too happy with this. As a precaution, I applied cyanoacrylate to the perimeter of all the carbon fiber plates to see if this will help.
I’ll update this post if I decide to go to some other frame. This might not be too bad of an issue depending on your flight style and the actual price of the frame. As I was writing this piece, the frame is available for less than what I originally paid for it.
As I said, I kept using my trusty FrSky XSR receivers. Otherwise, I would have gone to the FrSky R-XSR receiver, which is even smaller and has all the features of its larger cousins. I use SBUS for control and SmartPort for telemetry. If you go this way, make sure you get the version with the additional solder pads if you plan on running FrSky telemetry, as you might not have enough onboard inverters or available pins in your flight controller board.
While the motors I used during 2017 were perfectly fine, I decided to step up a bit mainly because those motors are being discontinued. I went for some well built, off-brand 2207 2700KV motors. In my experience, apart from cosmetic and marketing reasons, off-brand motors perform as well as their more expensive counterparts. And they are usually cheap enough that post-crash damage is easily fixed by replacing the damaged motors. Just buy them 6 at a time so you always have spares on hand.
Note that the motors I chose have short shafts, so you’ll most likely need low-profile lock nuts to keep your props together with your quad. They also use Japanese bearings, which should make them even more durable. You’ll find many similar motors such as the EMAX LS2206 2700kv I listed below. Check your prices and get them from wherever you’re more comfortable.
- RCX NK2207 2700KV FPV Racing Motor from myrcmart
- RCX NK2207 2400KV FPV Racing Motor from myrcmart
- EMAX LS2206 2700kv Brushless Racing Motor from Amazon
I went with the EMAX Formula Series 45A ESCs for my 2018 builds. This seems like an inexpensive, well-supported ESC. 45A was more than enough for my configuration and style of flight.
As usual, I bought 6 to have some spares available if needed, as ESCs sometimes release the magic smoke when bad things happen. I run these ESCs with mostly default values, disabled throttle calibration and DSHOT600. So far with great results.
Since I found no reasonably priced F7 flight controllers providing all I wanted, I went with an F4 AIO board made by DYS.
My experience with it has been mixed, but I like the format and features very much, so I persisted. Long story short, I ordered two units from MyRcMart. One of them worked perfectly, the other was irresponsive to USB. I would simply light the red LED and sit there doing nothing. MyRcMart was great about this and helped me get in contact with DYS, which responded very poorly. MyRcMart ended up refunding the failed FC and the shipping back to a US mailing address, which is cool.
Since the above happened during the Chinese New Year, I decided to order a replacement from Amazon, which I received the very next day. It was dead in exactly the same way, so I used my Prime superpowers and returned it. I got another one from Amazon, and this one worked flawlessly. The working FC from Amazon was from batch 2018.1, in case this matters.
All in all, this is a great design integrating OSD and PDB with an F4 processor. If you follow Oscar Liang’s tips on getting uninverted S.Port, you’ll get fully functional telemetry with your FrSky receiver. Just keep in mind that in the flight controller manual, the serial port 3 pads are mislabeled. I had to wire the telemetry pin to the RX3 pad.
- DYS F4 V2 Pro Omnibus Flight Controller AIO OSD from MyRcMart
- DYS F4 V2 Pro Omnibus Flight Controller AIO OSD from Amazon
I was a little hesitant about moving to a different VTX format, but ended up choosing a video transmitter that would mount on the same tower with my flight controller. I also wanted to be able to change power settings and channels over my OSD. I chose the AKK FX2 40 channel transmitter for maximum versatility.
This VTX uses SmartAudio to communicate with the flight controller and accept configuration commands, offers 25mW to 800mW configurable output power and supports Raceband channels. The price point was very reasonable and it came with all cables and pigtails so the mount was pretty easy.
There are some pretty good flight cameras to choose from. I was looking for a lightweight and affordable camera offering better resolution and dynamic range than the CMOS I was flying before. I chose the RunCam Swift Mini 2 camera. This is a CCD camera with good dynamic range in a package designed for FPV, so it would easily fit on my quads.
I hope you found this useful. Please share and email me if you have questions or comments about this post.