Epoxy Mixing Tray

I like to mix epoxy on a non porous surface. I used to use glass but as left over epoxy builds up it gets more difficult to mix. I included a photo of my old mixing tray. My tray uses parchment paper as a disposable liner. You can use it from a roll or buy precut 4"x4" sheets. You can either  lay an oversized sheet on the main part and snap on the trim piece, or use the trim outer edge as a guide to cut 4"x4" piece, or use precut sheets. To change the sheet hold the trim by the edge and press out the main part at a corner. Don't try to snap it together without a sheet in place. It prints with the top sides down and no supports. Layer height doesn't seem to matter. It is also stackable if you want to make as set of them.