C (forward slash) F = Stands for carbonfibre, in my day job I design and use high speed robots for injection molding machines, 13+ G's acceleration, working with allot of vendors in the industry I got a garage full of the stuff as obsolete end of arm tooling, love working with the stuff, with right tools its as easy as working with balsa, and I usually have allot of usefull bling on my models,
The german spelling is my prefference cause one of my vendors has a complete carbon modeling shop that acts as an offsite university coarse, proffesors are subsidized by the government as employees. Boeing has a manufacturing plant there as well, Bremen DE. like going in a modeling candy store. Autoclaves and a wall full of precision resin dispensing machines. Racks of cloths, tow, foams and knowledge all in one place, my bucket plane list of something giant scale gasser on the ama waiver list is gonna be loaded with the stuff.