Many hobbyists making and painting models and miniatures use containers for mixing and thinning paint, either for hand brushing or for airbrushing. One of the containers used for this is a 30ml plastic cup, widely used in the medical community for giving pills or liquids to patients; it is a convenient size, cheap, and disposable. However, because it widens noticeably from base to rim, if you use a mixing stick and leave it in the cup, it becomes liable to tipping over, spilling paint across your work surface.

In a recent YouTube video, I watched the presenter showing the use of a PVC pipe end cap to hold one of these cups, and I remembered a set of stabilizing bases for Tamiya Thin Cement and panel lining inks that I had 3D printed, thinking that I could do the same thing for these cups. The shape of this holder would be the frustum of a cone, with a similar conical cutout to hold the plastic cup. A bit of work in OpenSCAD, and I had a design that held a 30ml cup securely and had a base wide enough to make it unlikely to tip over.

The holder is a very simple shape, and is sufficiently sturdy with no infill for normal use, although if you want more weight in the holder, you can add infill.