This is a mini sandpaper holder I use to smooth some PLA printed pieces. I mainly use it for surfaces that were in contact with supports and were really rough.
It is really easy to use and it is composed of 3 parts.
And I have also added a cutting helper to cut the sandpaper sheet to the perfect size so it fits the holder.
Watch the video if you want to see how to assemble it: https://www.youtube.com/watch?v=aWROrL7pN2c&feature=youtu.be
You need a support for the handle