I found building this quad to be a very fun and interesting challenge. I had never built a drone using individual ESCs and a PDB before so I was excited to try a new style of build.

The Project399 page for this frame has a recommended build layout which suggests 3115 900kv motors so that's exactly what I used, the Brotherhobby Tornado 3115 900kv motors. I thought individual ESCs were a better choice than a 4-in-1 for this particular drone so I went with the APD 80F3 ESCs which can do ProShot1000. I also went with the APD 360A PDB because I figured the layout would be compatible with the ESCs and I knew it would be a reliable PDB. I got the SpeedyBee F7 V3 flight controller mostly because I have a SpeedyBee F7 V2 in one of my 5" quads and I really like it. I think the layout is nice and I've never had any problems with the BEC or any components on it and the bluetooth is really convenient. I recycled a Crossfire nano RX that used to be in a bind and fly cinewhoop like a year ago for this quad but only just realized the immortal T is missing an end cap. I put the HDZero Freestyle VTX in the back but I needed the Super G HD conversion plate or the standoffs would have been too narrow for it to fit.

I built this drone starting at the PDB then out to the ESCs and motors and then doing the flight controller, receiver and VTX. I usually start with the motors and then work inward on my drones but I wanted to make sure I got all the wires routed right and the correct length first. I was really satisfied with how my joints came out looking on the PDB and the ESCs. I don't have a ton of experience soldering with thick gauge wire so it was difficult at first but I figured out a technique that worked and gave me acceptable results. I'm using a 6s battery but this PDB doesn't have a dedicated voltage pad to power the FC from so I soldered my FC's power wire to the PDB's positive terminal for motor number 2 since it was in the vicinity of the plug. I didn't want to power my flight controller from a regulator because it can handle 6s voltage and I wanted to get onboard battery voltage sensing for my OSD.

I ran into a few problems during this build as well. After I mounted and soldered my ESCs to the PDB I noticed that two of the lock nuts holding in the arms align perfectly with the PDB's positive pad for motor 2 and the ground pad for motor 4 and that the PDB sits low enough on the stack screws that the lock nuts touch both of those pads creating a short circuit. I fixed this by adding a 3mm spacer above the bottom of the stack screws which gave clearance for the pads to not touch the lock nuts. This took away the room at the top of my stack screws to secure the stack with a nut on top. The next length of screw I had were 30mm screws which were too long and extended past the top plate so I filed them down to about 23mm so I could add a nut and secure my stack. Another problem I had was with mounting the VTX. After I had finished the ESC to PDB wiring, the wires for the back two ESCs extended further into the back of the frame than I thought, taking away my ability to mount the VTX flat and facing forward. Instead I decided to mount the VTX diagonally which ended up working really well but it made plugging in the firmware update cable a little cumbersome. I also lost one of the prop washers which is very unfortunate.

I was still waiting on a 3D printed gopro mount to come in the mail but I was ready to test fly this quad so I decided to do the maiden flight with no gopro. I checked my configuration before finally putting some enormous props on and taking it outside.

Maiden flight video:

For weighing about 1500 grams this thing floats like a feather, it hovers way lower in the throttle than I expected. It looks and sounds so cool when it's flying so I'm pretty pleased with my build. I think the coolest thing is seeing the drone's shadow because it's so big. I was really pleased with the performance of the HDZero Freestyle VTX as well, I didn't fly very far but it was able to penetrate through my brick house about as well as analog video transmitters of the same power do. I thought this quad flew pretty okay on betaflight defaults although I did notice some bounce back on the pitch axis. I checked blackbox and it seems like there may be some kind of mechanical problem because the gyro is picking up excess noise. I made sure to go around and tighten all of my screws after that flight. I also added a spacer between the PDB and the FC because they looked uncomfortably close.

I found a way to mount my gopro with some foam and a battery strap and charged up a 2250mah 6s battery and weighing in at 1537 grams, it flew for four minutes down to 23.2 volts. The center of gravity isn't quite right with the 2250 so I'll probably get some larger batteries for this quad.

I don't know if bigger is always better but in this case it's really really cool. I enjoy learning how to use different types of electronics and problem solving when I run into issues so this was a lot of fun and as always, very satisfying.