Some may find uses for this.

[Scrappile]

I can't afford a 3D printer, this could be used as a cheap alternative for somethings I can think of in one if I had it.

 Then there is this follow on video that I think is also useful...

 

[Joe W.]

Interesting - when I was flying a powered paraglider, every once in a while the tip of the carbon fiber propellor would strike on the edge of the metal propellor guard (pilot error) and break out a piece of the tip.  The repair tip passed on to me was to add drops of super glue to the hole and then pack it with baking soda.  then shape it with a file.  It saved me a lot of money over the years.
there are also small "micro glass beads" available that can be used the same way.  
But beware - wear a mask - they are like dust.