Having just bought a second hand quad to find 2 out of 4 arms delaminated before even flying and no spares in stock anywhere outside the US, I decided to try cutting my own carbon (I already own a small CNC machine but only cut wood before!). Yes the machine lives in a sealed enclosure with dust extraction.
Scanned in and traced the part in CAD and they came out really well. Photo of the new part (glossy) next to the old:
A lot less worried about crashing now I can just make a new arm in a few minutes! So if anybody needs something specific or hard to find cut from carbon fibre sheet let me know. I may be able to help.
It’s probably worth mentioning that the carbon on the original arm is oriented differently to the one you’ve cut, the idea is it’s not in a horizontal/vertical orientation to reduce the risk of snapping along the lines of the carbon. Having said that if it’s just a case of cutting a new one if it does break it’s not exactly the end of the world. I think it’s great that you’re in a position to be able to do this but just thought I’d let you know that the weave alignment is something to consider in future ones.
Fair comment and not something I had considered but certainly makes sense. Easily remedied by just rotating the CF sheet before cutting. Will bear it in mind thanks.
What cnc machine do you have? and where do you get the carbon fibre sheets from? I am thinking about doing the same but adding extra strength on my Flywoo frames where the motor mounts as it’s a weak point and breaks quite often. I would like to have a stronger frame and add a bit of weight rather than rebuilding the drone after breaking it.
It’s a fairly basic 3040 CNC machine branded ‘Vevor’. I’m not sure if the same one is still around but seems to be similar to a lot of other unbranded 3040 CNC machines. Was about £300. 30x40cm cutting bed (hence the name). There are also 3018 machines available for cheaper if you don’t need to cut that big. I get all my milling bits from Rennie Tools.
For carbon fibre there are a lot of sellers on eBay if you search for 3 or 4mm sheets of 3k carbon fibre. Probably not the best in the world but I’ve not seen any obvious problems. Unmanned Tech also sell it but limited stock availability right now.
So if anybody needs something specific or hard to find cut from carbon fibre sheet let me know. I may be able to help. 
