Hey, I just revieved my second shapeways puzzle. It is made of the standard WSF materiel. I know that a tumbler can be used to make the pieces smooth on the outside and "broken-in" on the inside. How much would the tolerances need to be adjusted to ensure that the inside surfaces don't become too loose? Rather than risk tumbling the whole puzzle, I think I will lightly sand the outside for a good finish (which needs to be done very carefully to make sure all pieces are uniform. I know that the material gets dirty easily, so a non-porous finish should be better. For my puzzle here: http://www.youtube.com/watch?v=nJrmYQsJyo4 I had to sand some internal pieces for a non related reason. I noticed what I did sand had a very nice finish. In the meantime, I think that I will clean the standard WSF finish the best I can. Is there a method to wash it? is that a safe idea? Thanks!! sorry for all the questions, but I did look elsewhere before I posted this. Answer whatever you have had experience with. Happy Cubing!