Price / performance and durability

A piece of Plexiglas with a logo on it for 10 Euro is very daring, also the thing still wears quite fast and you get hardly any wax from the surface when the edges are round.
My sword now held around 2 annual where I have my skis only once every few weeks waxed fresh. Now I could either still buy such overpriced plastic disc or alternatively follow the current with a 35-euro sharpener ...

I think I try it with a rough flat file and if that does not work I'll buy at the hardware store a piece of Plexiglas.