URUAV UZ85 DIY Kit Review
• Chris Landa
When I first saw the URUAV UZ85 on Banggood, I could not believe it - a 85mm copter for 78$? I have to try this one! When I received it, I was wondering about the package - why is it so small - did I get the wrong item?
I check the label on the box, it clearly says: URUAV UZ85. I open it up and in an instant I understand the low price: You get the parts and have to assemble it yourself. In the meantime the product description has been updated and states that it is a kit. On most of the product images you only see the fully assembled quadcopter, so I can understand how people (read: me) could get confused by that.
Thanks to Banggood for sending me one for review.
Overview
The parts are basically all plug and play, so the build should be done quickly, right? Well unfortunately not. Although you should be technically able to plug the camera into the flight controller, once you do, you have to really squeeze the flight controller onto the frame and thus put a lot of stress on the wires of the cam, but more on this later.
Parts
As mentioned above, you get all the bits and pieces needed to build a 85mm brushless whoop, but you need to assemble it yourself. Let’s have a closer look at all the parts now.
Flight controller
As flight controller you get a CrazybeeX v1.0 board. A 5A, all in one flight-controller. And this one really has everything on board: flight-controller, ESC’s, SPI receiver and even a video transmitter.
Since the copter is intended to be powered by 2S batteries, a XT30 pigtail is already soldered to the flight controller.
Unfortunately a cap is not included with this kit. Since I had bad experiences with some of the older crazybee boards, especially when running them without the cap, I would highly recommend you add a low ESR cap by yourself - if you want to be on the safe side. That being said, I ran well over 20 packs through the copter without a cap, and did not have any issues, so maybe I am just being paranoid.
This flight controller makes up already more than 50% of the kits total price. If you buy it on its own, you will pay 50$ just for the flight-controller.
You can get the flight-controller with FrSky or FlySky receiver. If you want, you can even get it without a receiver and run your system of choice. Since I wanted to test this highly integrated board with its full feature set I went with the FrSky version.
The Betaflight target is CRAZYBEEF4FR and mine came with version 4.0.x pre-installed. I immediately updated it to 4.2.3.
The video transmitter - although being on board - is internally connected via UART 2 and you can adjust it via IRC SmartAudio. The output power is 25mW and can not be increased - which for me, being from the EU, is not really a big deal, but is definitely something you might want to consider.
The quality of the video signal is OK. In my opinion all my whoops with dedicated video transmitter have a better signal quality. On the DVR i can see, that there is a bit of flickering, but it is not as noticeable in the goggles as it is on the DVR recording.
You can flash JESC or BLHELI_M onto the ESC’s if you want to enable ESC filtering. I opted to go with BLHELI_M and 48kHz.
Camera
The camera included in the kit is the Caddx Ant Lite. A form-factor smaller than nano, but you can still adjust some settings with the included joystick - which is really cool.
Unfortunately the aspect ratio of the cam is 16:9 and not 4:3, this might put off some pilots. Personally I don’t really care too much about that, although I prefer 4:3. (The cam I linked is 4:3, at least according to the product description.)
As you might know, I have not been the biggest Caddx fan, and I did not have any luck with this one either. Although I did not have dirt on the sensor, I have black corners on the bottom of the FPV feed, indicating that the lens is not properly centered over the sensor. Since this assembly is glued together, there is no real chance of fixing this. I have seen other people have black corners on top and some do not have them at all, so it seems to be luck of the draw. Other than that it is a pretty impressive cam for its size.
The wire is pre-soldered to the cam and you can just plug it into the flight controller.
Motors & Props
The motors included are URUAV branded 1102, 10000KV motors. They have a 6.6mm, three hole mounting pattern and you can plug them directly into the flight controller. You get two of the motors wired up for spinning clock-wise and two counter-clock wise. So if you mount them correctly, you do not even need to adjust anything in BLEHLI.
The motors do not have the greatest finish, you can actually see the tool marks on the top of the bell, but honestly - this is no big deal. The motors have a 1.5mm shaft diameter and you can basically run any 2 inch prop that you like. Included is one set Gemfan Hurricane 2023 props.
I would have preferred the motors to have a 9mm, 4 hole mounting pattern since you have more frame options with that size.
Frame and Canopy
The canopy is the same one that comes with the UZ65, has four mounting holes for securing it to the frame and two screw holes on the side to mount the cam. The camera angle can only be slightly adjusted, maybe by 10 degrees, so the cam angle will be between 30 and 40 degrees.
I wish you could increase the angle a bit more - if you are racing, you can definitely push this copter quite hard, but the cam angle really limits you.
The frame seems to be pretty sturdy (even after a couple of crashes on concrete, there are only a couple of scratches), unfortunately I could not find it as a single part on banggood yet - I am pretty sure that they will stock it sooner or later - at least I hope so, because there is only one other 85mm frame that will fit those motors and it is the one of the URUAV 85.
The battery mount on the frame is made for 2S LiPo’s that are sized similarly to the GNB 2S 450mAh batteries, that I like quite a lot.
If you want to run different batteries, you might have a hard time to mount them in the slot. In this case I recommend to cut the battery tray off and simply run a small velcro battery strap instead.
Assembly
The assembly is pretty straight forward, and everyone who has ever built a brushless whoop should not have a problem putting it together:
- Mount the motors onto the frame: The motors with the red wires spin clock-wise and go to the front left and back right, if you are planning on running props in. Black wires spin counter-clock-wise and go to the front right and back left.
-
Attach the cam: Here I would highly suggest to snip the plug at the end of the wires and solder the wires to the back of the connector on the flight-controller. As mentioned in the intro, when you plug the cam in, the fit will be super tight and there will be a lot of stress on the wires, risking that they break. Alternatively you could also cut out a piece of the frame to make space for the plug, if you absolutely do not want to solder.
- Prepare the canopy: The kit comes with a small bracket which goes over the lens and is pushed to the end of the lens, not onto the groove. Once inserted you pinch the canopy (from top to bottom) and squeeze in the lens, so that the grove of the lens is basically locked into the cam cutout of the canopy. This step is important, if you do not mount the cam properly, your feed will have a lot of vibrations. Once you pushed the lens through the canopy, secure the bracket by screwing it in through the side holes of the canopy.
- Mount flight-controller: Insert the rubber grommets into the corners of the flight controller, and slot it onto the frame. Once this is done, screw the canopy to the frame, double check the direction you put in the flight controller and then make sure you mount the canopy in the right orientation.
- Plug in motor wires: Next step is to plug in the motor wires. I like to twist them a little bit, which makes them neater and a little bit shorter.
- Mount the props: last step is to mount the props. I would highly recommend to screw them down or use the “floss trick” to secure them to the motors, otherwise they spin relatively easily and will come off.
The weight after assembly, without battery, is only 38.5g - pretty light weight for a 85mm whoop.
Performance
As mentioned before, I installed Betaflight 4.3.x, BLHELI_M and enabled RPM filters. If you are interested in my settings, you can download them here. After playing around a bit with the settings I have basically no yaw washouts when coming out of dives and prop wash is also not really an issue.
I really like the performance. With a 2S, 450mAh battery I can fly in my flat for a bit over nine minutes - this is pretty insane. It is also the first 85mm sized whoop that I can fly without any issues in my flat.
In the parking garage that I frequently fly in bad weather I get around seven minutes of faster cruising and a bit over four minutes when I really try to push it.
You can also do acro without any problems.
The whole rig gets pretty hot when idling, but as soon as you fly, this is no longer an issue. Motors come down cold, even with pretty lax filtering settings. Still, I would highly recommend to have a fan blowing on the copter if you are going to let it idling on the bench for a longer time.
Conclusion
Just by looking at the prices of the parts if you buy them separately, you can see, that you get a pretty good deal with the URUAV UZ85:
| Part | Price |
|---|---|
| Flight-controller | $49.99 |
| Camera | $13.99 |
| Motors ($9.61 x 4) | $38.44 |
| Props | $3.59 |
| Frame | $4.99 |
| Canopy | $3.08 |
| Total | $114.08 |
Obviously you need to consider if you would have gone for exactly those parts, but if price was a concern of yours, your build might have looked pretty close to that.
You basically save $36.09 (almost 1/3 of the price) by buying this kit instead of individual parts.
Apart from the oversight with the camera plug, I think this kit is a pretty great deal. Obviously I would like to see this fixed in a later iteration of this kit. Apart from that, I would also have liked them to include a cap.
I am also not a big fan of how the cam is mounted. If you crash, chances are, that the cam will be pushed into the frame and you need to re-adjust it. In terms of durability, this might not even be so bad, at least the lens will survive, but still it is a bit annoying since it already happens on fairly light crashes.
If you are looking for a cheap beater whoop - for example, when participating in IGOW - I can highly recommend this kit.
Chris is a Vienna based software developer. In his spare time he enjoys reviewing tech gear, ripping quads of all sizes and making stuff.
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