This is my attempt at making a micro quad with enough room for a 4-board 20x20 stack: 4-in-1 ESCs, FC, Runcam Split 3 DVR board, and the VTX. This is my second custom orange frame, and you can see a comparison of sizes between the 2 in the photos below.

Frame

The frame was custom made on my own Bantam Othermill Pro, using a diamond-coated bit and cutting under oil. It's loosely inspired by the HGLRC Hornet, which also uses just 2 side pieces and 2 spacers, and captive nuts to hold the roll cage in place. I sandblasted it and painted it - not exactly too satisfied with the paint job but I'm not a perfectionist. The frame ended up being kinda heavy, and looks kind of fat, hence the name "Orange Hog". It definitely holds up to falls (at least on grass) as you can see in this video, in which the props fly off not once but twice!

After that I put on the 3-blade props in the pics.

Electronics

I used the Kakute F7 Mini mainly because I wanted to try out barometer-based flight modes in iNav or arducopter, but iNav was just not working right for me, I couldn't get the PID tuning right and was having terrible oscillations, so I switched to BetaFlight and voila, it worked great.

I used 1106s because I was worried about the weight of the stack and beefy frame, and this is definitely not a delicate flower of a build, at 128g dry. But it's handling pretty well so far, though I haven't tested extensively.

Camera

One of the purposes of this build was to use the Runcam Split 3 micro. The camera works great, as you can see in the video above - which is unstabilized but has lens distortion correction.

Challenges

First and foremost, my failure to get iNav working right with no crazy oscillations, so I gave up for now and just used BetaFlight. Weight is a challenge with this frame. On the other hand it's a tank, but is probably overkill. I plan to experiment with 2mm CFRP in the future.