I made this D18 as a concept. The 25mm version lead to a blob of death so I scaled it up to 30mm and it worked great. 30mm is however too small to paint with my brushes.

I'd recommend scaling it up to 50mm if you wish to paint it. You should realize 50mm is huge for a die.

I took no pictures after sanding. The kitty pictures are before any work was done.