I made a holder with plate to help me spraypaint my (miniature) models.
The plate contains 2 holes to fit in 40mm baseplates and 3 holes to fit 30mm baseplates.
Also I've added tree little collums to fit models without a base on. I use some nanotape or putty/clay for that.

I seperated the parts for printing, Use a little superglue and you're all set.
I hope it will help you with all your modelpainting and 40k hobby's.