The minute I saw this frame, I wanted it. Smaller brushless frames (i.e., 3″ and below) have always seemed super interesting to me. Could they be as fast as a standard 5″ frame? Do they handle the same? How do you fit all your kit in there? I already have a couple of brushed micros but they’ve never quite felt great, so I dove in.
The Atto DC130 is a cute 130mm frame with tons of room to fit full size gear and build style flexibility. I love it, and you should buy one. Read on to see how the build went!
The frame was kindly provided at a discounted price for review, so big thanks to Atto for this!
Unboxing & First Impressions
The Atto DC130 comes in a real slick package, making for a pretty exciting unboxing experience. Opening the box, you’ll find all the bits and bobs squeezed into some nice foam protection. This is my first “real” frame, so it was nice to get some good packaging instead of a large ziplock baggie filled with carbon fibre dust.
The base plate is 3mm thick with a whole bunch of mount points to fit whatever you need. I really like the look of the motor positioning, with the back motors being pushed in slightly towards the centre. In the centre, you can fit a full-size 30.5mm (M3) mount flight controller, or if you’re going for a smaller build, a 20mm (again, M3) mount controller. Towards the front, you can fit a full-size FPV camera using the usual HS1177-style tilt bracket. I was pretty impressed with how much space there seemed to be.
There are a few top plate configurations to choose from: nano (right), micro (left), and an additional piggyback plate that can fit on top of either (top left). This gives you a bunch of leeway depending on what kit you want to use, what style of build you’re going for, etc. Going for a super lightweight build with small components? Use the nano plate. Need to fit a full-size receiver in there and ran out of room? Hide it under the piggyback plate. Also, I didn’t realise initially, but Atto uses a standard set of plates for all of their frames which is pretty neat!
On top of all that, there’s a set of motor risers should you need them as the props spin pretty close to the stack. There’s also a 30.5mm to 20mm adapter (both M3) so that you can mount a tiny flight controller on top of a fat 4-in-1 ESC, seen in the top right of the box. They’re all cut out of carbon as well, so that’s pretty cool!
Beyond the frame itself, the bundled hardware seemed pretty good. Titanium screws, knurled standoffs, spacers, and all the usual stuff, all in a very green colour. I really don’t like the full knurled standoffs, so it was pretty cool to see a different style — knurled at the top and bottom, smooth in the middle. Included are also some little accessories: a nice XT30 connector, a keychain prop nut spanner, and a couple of Atto stickers.
I opted for a bit of a mix between small and big parts for this build. Some interesting bits I’ve never tried before: a micro all-in-one flight controller ESC combo from XJB (who!?) and a Runcam Swift Micro. But also, a full-size receiver with telemetry support and a race-ready VTX. I also decided to go for 4S batteries just to make this thing crazy. Check out the complete part list below:
- Flight Controller & ESCs: XJB 20x20mm F3 V2 AIO 25A (no longer available, but there’s this upgraded one instead)
- Motors: Emax RS1306 4000kV
- Receiver: FrSky XSR
- Camera: Runcam Swift Mini
- VTX: ImmersionRC Tramp HV
- Antenna: MenaceRC Stubby Raptor
- Batteries: Turnigy nano-tech 850mAh 4S 45-90C
Flight Controller & ESCs
Just a quick chat about this board combo. I’d never heard of XJB before. It seems to be one of these generic Banggood brands, but they’re actually putting out something unique? This thing is a full F3 flight controller supporting the latest Betaflight with 4x 25A BLHeli_S ESCs (2-4S) in a ridiculously tiny package. It consists of two boards, one being the flight controller and the other the ESCS. They connect via a set of pin headers, passing through 5V, VBAT, and ESC signals without any messy cabling. Standoffs are included so that it fits together with the pins inserted perfectly. The ESCs are BLHeli_S, which means you get that hot DSHOT 600, which is amazing considering the size.
The sizing does make the 25A rating seem a little dubious, and the VBAT pads are comically small, but I like it so much that I tried it on a larger 4″ setup and it seems to be working well so far. It looks like you can’t get this version anymore, but there’s an upgraded F4 version with built-in OSD, which sounds awesome. I’d like to try out the new version some time — though unfortunately it looks like they dropped the UART pins. No SmartPort telemetry or Tramp control, alas.
One thing to point out is that the mounting holes are M2. This was a small problem, seeing as the DC130 only has M3 holes…
I had a pretty good time with this build. It’s tight, and needed a bit more work than a larger build, but was pretty straightforward overall.
Mounting the flight controller was the main issue I had to deal with, what with the M2/M3 mismatch. There were a couple of options:
- Just screw it in tight and hope for the best.
- Heatshrink the M2 screws where it meets the frame to fill in the gap.
- Make a M2 to M3 bracket.
I tried option #1 just to see how it looked. It actually seemed pretty reasonable and held on tight, but I was worried it would end up vibrating around mid-flight. I didn’t try option #2 though Calum has had success with it, and in retrospect was probably the better option for space saving.
I ended up going full in with option #3 by designing and printing my own bracket. It consists of two parts, one for each side of the flight controller allowing for a gap for the battery strap. With these, I could secure the bracket to the frame with an M3 screw and nut, and then use M2 screws and standoffs to secure the flight controller. It actually worked out pretty alright and if you need it you can find it on Thingiverse in a few variants.
The problem with this is that I basically lost a bit of the space I should have gained by using a smaller flight controller. The footprint with the bracket ended up being slightly larger than a regular one, making a tight build even tighter at the base of the stack. As I said above, in retrospect, just heatshrinking the screw to stop it from wiggling around (and maybe using a washer) would have saved me the hassle and gave me more space. I do enjoy designing hot shapes though…
There were a couple of other issues, but none that were a massive hassle or anything of the sort.
The power pads on the ESC board are comically small. Like, not really sure how you’re supposed to jam 40+ amps into it without it bursting into flames kind of small. I ended up using a bit — or maybe a lot, depending on how you look at it — of hot glue to stop the wires from ripping the pads off.
On the motors, I ordered the wrong motor threading, so they all use counter-clockwise nuts. Apparently the choice of clockwise in this instance meant motor direction, not thread. Whoops. The motor wires were also too short up front, so I had to extend them. This is not really an issue but I suck at doing wire to wire soldering, especially when the wires are thin and noodly, so it mostly just made me grumpy.
For the top, I wanted to avoid using the piggyback plate if possible. Mostly to keep it simple, but also to keep it as short as possible. With the ImmersionRC Tramp, that left the micro plate as the only choice. This let me keep the power and video connectors towards the centre of the stack and squeeze the pigtail towards the back standoff.
It’s really tight. I still don’t feel too happy about the pigtail, but it hasn’t been chopped into pieces as of yet. The rear propellers spin a sniff away from that back standoff so it’s a genuine risk. Having the pigtail cable bent in such a way is also not ideal, but again, hasn’t broken yet. Later on, I might look at hiding my receiver underneath the piggyback plate to give me a bit more breathing space. At the moment, I can’t really see where else they could go!
Firmware & Telemetry
I flashed the board with the latest Betaflight and BLHeli_S without problem using the standard methods. There was some extra faffing that was needed for this board, specifically disabling motor 5 and 6, but this was done easily through the Betaflight CLI. I also set up a custom mix to deal with the rear motors being closer than the front.
Since I was using an XSR, this meant I could get telemetry out to my Taranis, giving me VBAT warnings without needing to deal with an OSD or a beeper. Additionally, since I was using the Tramp, I could also change channel and power through the Taranis with the magic Lua script. Doubly good. This meant I didn’t have to fit a TNR patch or ham around with the button. That said, I still need to try squeeze the patch in somewhere otherwise I can’t race with it! Where it’s going to go, I’m not really sure yet, but it needs to go on there somewhere.
Here’s some hot beauty shots of the finished build for your enjoyment.
And a quick size comparison in my averagely sized human hands. No banana for scale this time, unfortunately.
As you can see, it’s pretty damn tiny. I haven’t weighed it yet, mostly because I’ve never really bothered about build weight, but also because I literally can’t right now. At time of writing it is currently in bits after a whole bunch of hard crashes. It feels pretty light though, for what that’s worth. I’ll update this with a legitimate numerical value once it’s back together!
The Tiniest Of Racers
Now, the most important part: how does it fly? The build could be a total nightmare but if it flies amazingly, it doesn’t matter. Take a look for yourself.
Discounting my piloting skill, this thing is real speedy and highly maneuverable. Like, way more than I expected. I was expecting it to be kind of like a Tiny Whoop Ultra Mega Plus™ but it turns out that is a total lie. It handles like a full size quadcopter, except it’s small. It’s great.
One thing I noticed is that I could go round the track way quicker than I could in my 5″ build. Having a smaller quadcopter makes it easier to go through gates without crashing, obviously, but this let me speed up where I would have had to slow down in the bigger one. It also makes for a good time in freestyle, hitting tiny gaps without any problem. Even though the camera gives the same view as usual, you definitely feel smaller. It’s a pretty weird sensation to describe so I guess you’ll just need to build one to get what I mean.
Vibration & Tuning
So despite it flying pretty well, it does have an insane amount of vibration. Pumping the throttle to maximum visibly shakes the whole thing when looking through the headset. I don’t think this is the fault of the frame, though. It’s more than likely not the really crappy props I used it with initially. Kingkong props are usually pretty decent but their 3030s are bendy garbage-trash. After being shaken to death with the worst props ever made and taking a beating in the warehouse, the motor bearings have kind of exploded.
I originally thought maybe it was just poor tuning — i.e., Betaflight defaults are for larger quads, so higher than this needs, maybe? So I had a play around. Lower values helped the vibration a little, but it mostly just felt loose and awful. Higher values (for the sake of testing, the result is kind of obvious!) just made it vibrate worse.
The flight controller is hard-mounted, of course, so I could try a soft-mount solution. To fit it in, I would need really short rubber mounts as I’ve basically maxed out the space available. They would also need to be on the bracket, rather than the flight controller directly, as I’m yet to see any M2 rubber bobbins. I could also try o-rings as a last ditch effort, but it would basically be a placebo at this point. The M2 screws going through the controller tend to bind — they don’t allow the flight controller to move up and down very easily, even without the nut in place. I could maybe try it on the bracket… ? There’s a whole bunch of things to play with here.
I have new motors and good propellers to try, so hopefully I can update this section saying that everything is beautiful and it’s the most locked in quadcopter ever built.
New motors and better props solved the problem! I also started using Betaflight 3.2’s dynamic filtering and that helped a ton, too.
So to close it all off, despite the vibration issue, this thing is awesome. It’s only made me want to build more tiny quads and you totally should too. This frame is really great with basically minimal compromise as to how you want to build it. It’ll fit small components, or you can squeeze in full size components, or both. In general, there’s a whole bunch of different components and frames available that fit this size and below, so it’s basically the exact same as any other build.
The only downside is that it makes flying micro-brushed quads like the Tiny Whoop feel massively underwhelming in comparison.
Maybe an Atto X113 next…?