For an elective course called 'composites', we had to make our own drone. The students were divided in different groups who each had the responsability over a specific part of the race drone. The part my group was responsible for, were the propellers. 

The propellers were made of a composite made of basalt fibers and epoxy. This mixture was put between a 3D printed mold made of PLA and was left to hard out overnight. 

The next day, the molds were removed with the help of a hammer and a chisel. Since a lot of CR1 release agent was used, the propeller came off the mold pretty easily and thus was not harmed in the removing process. This means the same mold can be reused.

This is the result after finishing the deliverables.