 Recently I've built a 5" Freestyle quadcopter based on the best value components - not the cheapest but the best price/performance ratio (i.e. bang for buck). The components I've chosen plus comparison to alternatives can be found in the component selection article here. As it stands the build cost of this one is around $150-$170 depending on which specials you can take advantage of. I see the RC Addict (His YT channel here) has done a similar thing for a race build and he refers to it as the "The cheapest quad worth building" This quad has since been built, setup, flown, adjusted and then flown a lot more. I'm now in a position to pass judgement over all of the components and will then cover as the quad in total. For each I'll look at the positives and negatives and then go into a little more discussion with my recommendations
Discussion and recommendation
At the time these Emax Eco were chosen as they were the standout budget motor. They have been available for $10-$12 and based on how they perform represent outstanding value - the top equal standout recommendation for this parts list. Emax had the original breakthrouhg brushless motor in the quad scene - the RS2205s which changed the industry. While others have caught up since they still make well-researched high quality motors. The Eco series draws off the learnings from the LS and RS2 series - they remain VERY light but have increased the bearing size from 8mm to 9mm to improve durability significantly. Retained from the RS2 and LS series however are the thin magnets. Although these mean the motor doesn't make the same peak thrust as heavier motors with larger magnets, it does gain in improvements through being lighter, more efficient and smoother at throttle transition. This makes it a great match to freestyle where these positive attributes tend to be preferred over peak thrust @ 100% throttle. In use these are very nice motors to fly. They are quiet, smooth and cause less battery sag and longer flight time than more expensive motors I use such as the brother hobby returner R6 2306. Interesting that based on the success of the Emax Eco, iflight and brotherhobby have followed suit. 3bhobby also have the training motor although this may have just been out when the emax eco was launched.
Discussion and recommendation
The price of the diatone mamba stack cannot be overstated enough, there is simply nothing anywhere near in this category let alone a set that can run up to 6s with the diatone name. This is the single biggest standout item if you are looking to take price out of your build without compromising featureset or reliability. The Diatone Mamba F405 uses an F4 chipset which is the standard at present. At time of writing there is nothing practical in Betaflight 4.0 that you miss when using an F4 rather than a F7 or greater chip. The Gyro is the MPU6000 which is now recognised at the most suitable with current technology and does not require soft mounting. There are 3 UARTS and since your receiver takes one and the it's fair to assume that smartaudio/tramp control takes another then that only leaves one spare: GPS, camera control, runcam split control etc. will need to fight it out although these are not especially common uses. The BEC on the FC is supposedly 1.5A and I'm pleased to report that in my build at least it offers a clean power supply for my VTX and Camera (no lines or other interference on throttle change). The F40 ESC is rated for 40A continuous and 50A burst which is fine for any modern 5", most 6" and some 7" builds. What is most pleasing is that it is rated for 3-6s operation. I have used mine on 6s 80% of the time and it hasn't skipped a beat. It's a shame it isn't BLHeli_32 but the only real advantage to that is telemetry feedback and the as yet mostly untapped potential to run RPM filtering through betaflight. It does have a current sensor which is easy to calibrate and works well. The kit also comes with the good basic accessories as noted above so as not to slow up your build. Two minor gripes: I miss the option to have battery wires come up perpindicular from the board like on the Airbot Typhoon V2.3; when present this makes it easier IMO for a topmount battery like this build. Secondly the fact that the outer-most motor wire pad juts out at the corner of the board beyond the mounting plate means wiring is a little less clean although I'm getting nit-picky now.
Discussion and recommendation
Frames are notoriously hard to choose as they depend a lot on the individual however since this is for a freestyle build I wanted very centralised mass due to a lot of flippy flops. This let me to a true-x slammed design. The reason I chose 5.5 inch over 5 inch was to allow the props more room to unload air rather than force it though the tightly packed fuselage thereby offering better yaw response (supposedly). Looking at the iflight xl5.5 lowrider specifically I flight have got what feels like a reasonably premium item at a moderate price ($35ish) so that fits the brief. It was easy to assemble the frame with the instructions but room for the stack is very tight - 2 boards only. This was a bit of a shame since I like to mount the VTX as part of the stack. Nevermind, more room in the tail of the frame for that. Also there is the option to mount the arms below the bottom plate rather than above but this increases the height of the frame and partially negates the point of having a slammed frame in the first place. I really like having the 5.5 inch size - it does give a 5" prop more room to move and also gives me the option of running 5.5 inch props I've I want to range a little further out. VTX antenna mounting is disappointing - and SMA sized hole in the top plate which is just a terrible option. I purchased this extra TPU print the let the antenna exit more safely at an angle. Overall it's a nice frame and it feels VERY durable (although no had any heavy crashes yet) but also consider something like the cockroach for a little less. This is a good looking little frame that's only $20-25 and is about 15g lighter. The TBS source one is also a nice option but is very heavy.
Discussion and recommendation
Not much to say on the runcam robin, for my part it works fine. At $25 it is the most budget camera in the runcam range. Picture quality is ok with 700TVL resolution. Low light performance is ok (see DVR for dusk flight). I'd prefer a little better dynamic range but again, not the end of the world. It was nice to have the included full size adapter bracket which I chose to use for the iflight frame rather than the TPU mounts for the XL5.5 lowrider frame. If I were to choose again I'd probably go for the micro arrow pro which is typically $5 less or more likely the caddx ratel which is about the same price on special but with a much larger sensor that lends itself to better low light performance and dynamic range. That said the robin is fine and has a typically high quality runcam lens. This DVR was recorded quite late on a winters evening, actually did low light better than expected but obviously not as good as a micro eagle.
Discussion and recommendation
I got this Eachine TX805 on a hunch it was made by AKK and judging by the performance I'm fairly sure I'm right. Performance for this unit had been really pleasing. little to no noise between on this one and reception is good and clear even on 200mW. Nice that it can go up to 800mW if needed but since this quad is for freestyle 200mW suits me well. Struggling to find something bad about this other than the fact that audio quality is poor which is very consistent with ALL vtxs with a built-on microphone. Very easy to recommend this unit.
Unfortunately inconclusive results here. My build did not lend itself to stubby antennas - since this has a top mount battery I needed an antenna with a longer stem so that the active element could clear the pagoda. The foxeer lollipop 3 stubby antennas are more suited to a race quad with bottom mounted battery - will report when I've had a chance to try.
Discussion and recommendation
I mentioned that frames are quite a personal and subjective choice, props are very much the same. That being said the Gemfan 5146.6 hurricane props are very impressive and actually cover most bases. They are light but have surprisingly good durability. As far as flight is confirmed they have a real Jekyll and Hyde nature - at low speed they have very good fine control and if found I could maneuver much more easy in small spaces than usual. However when you bought motor speed up they are very quick. Current draw of course comes up but still wasn't as high as I was expecting given the speed. Interesting that they were developed to Minchan Kim's race requirements and yet have ended up a suitable for freestyle as well. Certainly worth giving a try, they are my current favourite 5 inch prop. What about the quad altogether as a unit?
It flies really nicely down to the smooth emax eco motors and gemfan 5146.6 props. The Diatone F405 stack plays its part with stock betaflight 4.04 tune which feels perfect for this setup - it provides no more nor no less than what is needed. Runcam robin camera is fine but doesn't set the world alight in less than ideal conditions. I was really please with video signal which is down to the clean power supply from the flight controller and the suprisingly good eachine tx805 vtx. The Foxeer lollipop 3 antennas were a disappointment only for the fact that I should have chosen a regular stem rather than a stubby variant which was block on my build by the factory. The iflight xl5.5 lowrider frame was tricker than perhaps it needed to be by virtue of being a lowrider - I regret not being ably to make a 3-high stack with this to clean up wiring a little but the end result (clean video) has been achieved anyway. What was more disappointing is that I needed a separate TPU antenna mount because the stock antenna location (frame top plate) is poorly advised. Other than build challenges the frame is nice - compact, rigid and so far I can tell, very durable. It's looks do not excite me but functionally the centralised mass certainly appeals. Summary In summary since this build is something of a collection of parts, most of my thoughts are captured in individual components. I have taken pictures throughout the build however have not prepared a build guide. If you do wish to see this, please leave a comment below or on my facebook page - I will write a tutorial if enough people show interest. I have a day job where I am well looked after so don't need you patreon money nor your deposits to my bitcoin or paypal accounts. I recommend you keep that money for yourself and your family. I do use affiliate links at no cost to you to help fund the parts I need for articles like this - tips, tricks, ugrades and reviews. If you like this or other articles I've written please click on these product links to help me keep this going. Click on the links below to like or share on facebook and spread the word. Thanks :) 
1 Comment
|
