Mini watercolor palette

This model was made to store small amounts of watercolor paint (squeezed from tubes and allowed to dry) so I'd have something super-compact to take with me in my travel kit. Works well with a  water brush pen. I tend to activate the colors I want to use with a little water and drag them into the center of the palette for mixing. Here's what mine looks like after years of use, compared to a new one:

I also made a smaller version that fits in an altoids tin for a friend - the benefit here is that you don't have to make sure everything is dry before putting it away.

Some pigments and paints crack after a while - gouache especially seems prone to it. Most watercolors seem to work OK - press them down with a finger once mostly dry if you're worried about them coming loose. 

CAD model for anyone wanting to modify it: https://cad.onshape.com/documents/078c89e002520423f8e83df0/w/97441ec9eb07c806a187fd58/e/510cca624ca9899ab882990d?renderMode=0&uiState=65720d9a0a5c796bd3f5bee8

NB, mini-palette pictured above was a few mm too long so I trimmed it down manually. The file has been adjusted so this shouldn't be necessary. Paint the top of the tin white or light grey as an extra mixing space.