It is such a sublime feeling to be able to share with you my ZMR180 build. Initially, I began with the ZMR250 but I was looking to get something smaller in size as well that I could maneuver in tight spaces. Living in an urban locale, there are not a lot of open and wide spaces to fly but I am able to reach slightly tighter locations that are more suitable for smaller sized quadcopters.
The ZMR250 comes with a diagonal motor to motor distance of 250mm while the ZMR180 boasts a diagonal motor to motor distance of 180mm. This shows the difference in size of the two machines. Some time back, I had placed an order for an Almost Ready to Fly kit from FPVModel.com. But there were some issues related to customs clearance with my shipment and it got delayed inordinately.
Here is what came in the original bundle:
I had ordered the non-FPV kit since I already owned FPV gear. I will share with you my photographs of the FPV gear later on in the post.
- ZMR180 Carbon Fiber Frame: The frame consisted of three pieces of carbon fiber and red aluminum stadoffs. The bottom plate is 3mm thick while the top plate is 1.5mm thick. The frame seems to be formidable and quite smooth. It appears to be in a better shape as opposed to my Banggood ZMR250.
- Dragonfly 1806/2300kV motors: These are good enough motors. They are durable and quite attractive to be honest.
- FVT Littlebee 20A ESCs: These ESCs are great since they are loaded with the BlHeli bootloader and firmware. This enables you to reverse motor spin using the software and program all the ESCs via Cleanflight
- Matek 5-in-1 Power Distribution Board: The Matek Power Distribution Board is a great option for smaller sized aircrafts. It has an area of 36 x 36 mm and is of a size similar to most of the flight controllers. It comes with a 12V and 5V output for FPV gear and powering up the flight controller. You can also connect the FPV video wires into it.
- Naze32 Rev 6: Naze32 Rev 6 was the flight controller that is an upgraded version of the iconic Naze32. It comes with a barometer and 2MB of integrated flash memory.
- Dragonfly 4045BN propellers
- Other hardware: Battery straps, screws, heat shrinks, cable ties, wires and connectors. This is what is so exciting about Almost Ready to Fly kits since you get everything that need. Otherwise, you are bound to make several visits to the nearby hardware store to get the smaller things that did not come with your original package when you started building your own quadcopter
Here are some of the tools that you might require:
- A soldering iron
- Solder wire
- Hex screwdrivers
- A hobby knife or blade
- Philips head screwdriver
- Blue threadlocker
- Paint markers for embellishment purposes
All of the frame components come sealed in this blue plastic shrink wrap.
You get the motor itself, bullet connectors, propeller shaft, a propeller nut and some screws.
Step 1: The frame
As soon as I took out the frame out of the shrink wrap, I observed that some carbon fiber dust was sticking to my hands. This is so because the frame is cut with the help of sophisticated machines from sheets of carbon fiber.
Carbon fiber is not safe for respiration so I washed the frame components with soapy water and let them dry up.
I used a pair of tissues to get the components dried up early. This was my second build and I had toyed a lot with my first build. So, I was confident enough. I painted the frame edges with some Sharpie oil paint markers.
I applied a couple of layers of the oil paint. I ran the marker over the frame edges, let the paint dry up and then applied the next coat.
Some folks advise to coat the paint with nail varnish to prevent the paint from coming off during crashes. I did not have any varnish in my house but as soon as I get some, I will definitely apply a layer.
At this point in time, the frame was ready. Since there are only six standoffs and a single FPV mount, so assembling the remaining parts is quite easy. That will be accomplished once all the electronic components are put into their respective places.
Step 2: The motors
I put some blue threadlocker on the cardboard from the box and got back to work. It is quite simple to screw the propeller shaft. The motor shaft sticks out a little from the top of the motor so the propeller shaft will get fit right into it. Then you simply have to align holes in the propeller shaft with the holes in the motor and start screwing them.
I dipped the bottom of each screw into the threadlocker and got back to business.
The ZMR180 Almost Ready to Fly kit from FPVModel.com came with a couple of clockwise and a couple of counterclockwise motors. This is the direction in which the propeller shafts are threaded.
So, for clockwise motors, you have to screw the propeller nuts clockwise and for counterclockwise motors, the propeller nuts are screwed counterclockwise.
This is handy since two motors will rotate clockwise and the other two will rotate in the opposite direction. So, by using the opposite threaded motor, the propeller nuts will not get stripped off owing to vibrations when the motor rotates.
Once the motors had been prepared, it was time to screw them onto the frame. If you are using the Naze32 of Cleanflight on any board, you can view the required spinning orientation of the motors in the figure given below.
A drone enthusiast shared a handy tip to check if the propeller nuts are threaded the right way or not. Hold the nut still in your fingers and spin the motor in the requisite direction. If the nut tightens as the motor spins, then the threading is all right.
Step 3: ESCs
Now comes the turn for the ESCs. We are using the FVT LittleBee 20A ESCs in this build. They are compact in size so I had to trim the long motor wires. Since I did not want to trim them too short so I wrapped the motor wires from below the ESC, around the back and soldered them directly to the ESC pads.
If you are a rookie and not well-versed with soldering, then I would suggest you to splice the motors and ESC wires rather than soldering them.
Using a piece of some extra heat shrink that I had, I put it around the ESC, I shrank it down with a heat gun to ensure that it fit snug onto the ESC.
Then, I cut the heat shrink off all the ESCs and de-soldered the wires to connect the motors. This is so because I was planning to solder the motor wires directly onto the solder pads on the ESCs.
Here are the ESCs once they were ready.
Now was the time to solder the components. I positioned the ESC where the heat shrink on the motor wires ended and ran the motor wires below the ESC, then above it and up to the solder pads.
I made the motor wires into a bunch and brought them between the positive and negative wires on the ESC since there is sufficient space between these two wires.
Then I cut off the extra wires. I repeated the same process four times. So, the heat shrink was ready to be shrunk down.
Step 4: Matek 5-in-1 PDB
The Matek 5-in-1 PDB is 36 x 36 mm in dimensions and boasts a size similar to the Naze32.
It comes with four sets of pads for the ESCs in addition to one battery lead pad and another pad on the other end which outputs the same voltage as the battery.
When the terminals for the battery are wired in, ensure that you measure and figure out how you will be connecting the battery to the terminal once the multirotor is finished. The wire should not be too short as well as too long to get in the way of the propellers.
I ran the wire from exactly behind the quadcopter and plugged it directly into the battery.
I utilized the pad for my VBAT that I was supposed to connect to the Naze32.
The ESC pads are located in such a way that you can cut the wires as short as possible and no ESC power wires will intermingle.
We have a dedicated 5V output and another 12V output. I connected the 5V output as my BEC to power the Naze32 board.
Also, there are a couple of sets of outputs for the video transmitter and camera which is either 5V or 12V. There is a positive and ground pad and just next to it there are bridging pads titled as 5V and 12V. If you intend to use 12V, you can bridge those pads with the solder. If you want to use the 5V, you can alternatively solder the pads.
Both my camera and video transmitter were powered by 12V so I bridged the 12V for both. The PDB also presented the option of connecting the video signal wires. I connected it but the video feed was not how I wanted it to be. So, I removed the video wires from the PDB and spliced them together.
Once all the components were soldered, I covered all the open joints with liquid electrical tape.
Step 5: The Naze 32 Flight Controller
I placed the Naze32 right above the PDB and ensured some space between them using the nylon spacers that came in the original bundle. The spacers were 4mm in thichness.
I wanted to make this build look as clean as possible so I did not use any signal pins and direct soldered everything.
There were a couple of sets of wires from the PDB to the Naze32 and I soldered them to the bottom of the flight controller since the solder pads were located on both the sides.
These two sets were the main voltage which got connected to the VBAT pins. The 5V powered the Naze32 which I soldered to the pads for ESC 6. Since I had four motors, so the ESC pads 5 and 6 were vacant.
I applied liquid electrical tape to the underside where the wires were connected in order to prevent any short circuiting. I used nylon nuts to screw Naze32.
Then I connected the ESCs to the board. The motors must be connected to the flight controller in a particular sequence as shown in the figure.
I determined the length of each ESC signal wire to the corresponding pad on the Naze32 and add a few millimeters for safety and cut them in an angular fashion. For instance, for two motors, the signal wire had to reach a little farther than the ground wire and for the other two motors, the case was opposite.
I soldered the wires in and the motors were connected.
Step 6: The receiver
I used the FrSky D4R-II receiver for this quadcopter. The receiver is small in size, provides support for CPPM and telemetry. Moreover, it offers enhanced range and durability.
I cut off the plug from one end of one of the servo wires.
The Naze32 Rev6 has one line of outputs, the first pad is the ground, the second pad is 5V output and the third pad is channel one. The other pads are all channels but since I was utilizing CPPM so I only required a single channel.
The wire that had been cut was soldered to the respective pads and was connected to the channel one on the receiver. You will have to use the jumper and plug it into the pins 3 and 4 to ensure that the receiver works in the CPPM mode.
Owing the tiny metal contact in the jumper, the pins for 3 and 4 are shorted out and the receiver recognizes that it is supposed to send a CPPM signal.
The receiver comes with telemetry options and these are the wires that are located in the top right of the receiver.
To connect the receiver to the Naze32, you will be simply required to connect the RX and ground wires. To configure telemetry, I soldered the ground wire to any grounding on the PDB while simultaneously soldering the green wire to the receiver pad 6 on the flight controller.
You can also use the pad 6 for Soft Serial which is a protocol that can be used for telemetry. My Taranis comes with the latest firmware so it detects telemetry via soft serial only.
After all this, I simply had to connect the FPV gear and my quadcopter was ready for its aerial adventures.
Step 7: FPV Gear
I had already soldered the plugs for the FPV gear onto the PDB, so now I simply had to connect the camera and video transmitter.
After connecting the camera and the video transmitter, I connected the battery to ensure that the video signal was all good and also to determine the orientation of the camera.
Ensure that you figure out the correct orientation of the camera before you screw it up.
Initially, there was no video signal and I could only view blank screen. After some searching, I figured out that the camera wire had come loose. So, I soldered it to the video transmitter signal wire and removed it from the PDB.
I stuck the camera to the camera plate with hot glue and screwed the video transmitter to the top plate.
Step 8: Final touches
By now, I had connected all the components and tested them as well. I was now about to apply the final touches and get my build ready for its maiden flight.
The standoffs were screwed in. The top plate had a hole in the back for the transmitter’s SMA plug. I passed the transmitter through the hole and affixed it with the help of a nut.
I also required some space to run the antenna wires from the receiver. I accomplished this with some zip ties and made a couple of antenna holders at the back of the plate since I was going to need plenty of room for the battery and my HD camera.
I used Velcro to stick the receiver to the top plate. Once I made sure that everything was perfect, I screwed the top plate on and ran the antenna wires along the zip ties while placing a length of heat shrink on the antenna wires and zip ties to keep them in place.
Then I had to make sure that the battery would not slip off from its position. Bruce from RCModelReviews.com uses foam to do this. I took some foam, cut a slice and attached it to the top plate with hot glue.
Once the battery is attached to the battery with the help of a strap, sufficient friction is supplied by the foam and the battery does not move an inch. I used 4S 1300mAh batteries and found out the final weight of my build to be 417 grams. By adding my Xiaomi Yi, the weight would become 490 grams.
Step 9: Configuration
As I had hard-wired the ESCs to the motors and all the wires were straight, so I had the vaguest of ideas which way the motors would spin.
Fortunately enough for me, the ESCs are loaded with BlHeli bootloader that lets you configure all the four ESCs instantaneously by connecting the Naze32 into the computer.
Else, I would have had to use the Arduino tool and flash each ESC individually.
To determine the direction of rotation of the motors, I simply had to figure out the direction of rotation of a single motor.
I pinched the propeller nut and spun the motor and via BlHeliSuite, I gently increased the throttle on the motor. If the nut tightened, the motor was spinning in the right direction. If the nut loosened, the motor was spinning in the wrong direction. The motor that I was testing was rotating in the wrong direction so I used BlHeliSuite to reverse the direction of rotation of that motor and the one diagonally opposite to it.
My mini quadcopter was ready for takeoff.
I carried out some minor changes in Cleanflight and was good to go.
I plan to do another post on the Cleanflight configuration in the coming days.