Upon addressing multiple requests to make many different kinds of test tube stands I realized there never is a one size fits all stand.
Therefore I created this fully customizable test tube stand, that you can easily modify to suit your needs. It already includes hole sizes for a handful of the most common tube types (Eppendorf 1.5 ml, 2 ml, 5 ml; Falcon 15 ml, 50 ml and Flow cytometry tubes). However, you can also set a custom hole size as well as spacing for any kind of tube or cylindrical object you wish! Maybe you can even make a pen holder out of it :D.
There are plenty of other modifications you can make such as adding text on the side to mark your stand, changing the thickness and height of the stand etc.
I hope you can generate the stand that you always wanted but never found someone to design it :)
Let me know in the comments if you want more features or tube sizes to be added!