First: I’m usually not a fan of ducts, but there are situations where some protection matters…
While there are some mixed reviews on the BNF FSD Tiny Leader (their ESC seems to burn on 3S, bummer), their frame kit is available for very cheap from various sources (BG, xt-xinte (complete frame kit less than 9 USD)) and you can buy a full set of ducts with the necessary screws to mount them for below 5 USD. The frame kit is pretty nice for the price (1mm CF plate, 4 really good ducts, screws etc., 3d printed canopy of questionable print quality (still usable)).
I went ahead and built a machine using the well known cheapo BR1103B 10kKV using the standard frame kit and I have to say the durability of the frame and ducts is stellar.
After countless hard crashes I broke one duct yesterday and noticed that the material behaves a bit like hot glue when heated with a hot air reflow, which makes tiny fixes really easy (it turns transparent when it’s hot enough and turns opaque after a short time of cooling). Doesn’t look like new, but gets the job done.
TL;DR: That frame kit is highly underrated. Combined with the right components you will end up with a pretty awesome little machine.
- FSD Tiny Leader Frame Kit
- TBS Unify Pro Nano (custom BF 4.0 firmware to make the SmartAudio work)
- FrSky RXSR (flashed to the latest FPORT firmware)
- FXT T80 (highly underrated camera IMHO)
- 16x16 Flightstack: BS06D 4in1 ESC modified with automotive FETs (works on 3S when modified properly, tested on other interesting machines for over half a year) + the corresponding HappyModel Super_S F4 (I found a version that works fine on 2-3S, probably more)
- BR1103B 10kKV Motors
- KingKong/LDARC 1535 Props (38mm)
- Misc mounting hardware: Some plastic and 7075 screws, 1mm nylon M2 spacers etc.
- Misc parts (XT30 + Tantalum caps, silicone wires etc.)
- GemFan lies about their prop size of the new 16XX props. They are not 40.8mm in diameter but slightly larger. These props probably fit when your ducts are in mint condition
- Using a smaller prop might be less efficient (KK 1535 in this case), but way more fun. The ducts can actually protect the prop since there’s enough clearance. I didn’t brake a single prop on this machine yet.
- The ducts are made from a really good and easy to fix material.
While this is all working nicely and the frame kit is really easy to use, I want to design a custom CF frame for the ducts. Maybe a top mounted battery setup (not sure about that), but at least I want something where I can properly mount the XT30 to the frame.
I’m also looking for a proper 1102-1103 motor with M2 standard mounting pattern (4 screws, not 3.) in the 10000-11000KV range, but all candidates I found are not really promising.
It needs the standard landing pattern AND a bell with M2 screw holes to mount the props (not going to use press fit props).
Maybe we can come up with a way better design using the original ducts (they are currently very affordable) - if there’s enough interest this might be a nice community project.
I’m open for suggestions - discuss! Maybe I’ll post some pictures later.