These test strips are designed to test various glues for use with PLA (although of course it could be used to test other filament types as well). Each piece has a flat side, and a side with two hemispheres. The hemispheres are sized so that the smaller one fits inside the larger one. Glues can be tested by either gluing the flat sides together, or by gluing the nesting hemispheres.

The strips should be printed in pairs; the provided files will print eight pieces (one at a time) in one print session.

You can find the results of my tests of various glues at the link below. I tested by gluing the two hemispheres, and allowing the glues to set overnight:

https://docs.google.com/spreadsheets/d/1X0eDE9vAzqW7su0Wc4lyf9exsdFXaT9sGLRibPlYwS8/edit?usp=sharing

I think my choice would be 3M Super Strength - it's easiest to use, the 10 minute working time gives you plenty of time to get things in the right position, but it still sets up pretty quickly. Unfortunately it seems to have been discontinued - I don't know if the replacement (3M Maximum Strength Adhesive 6047) is as good or not. Another good choice would be super glue gel, although it does not give you much working time.

The OnShape 3D CAD file for this is available here:

https://cad.onshape.com/documents/4bbcaea582a17bbe402bb560/w/a63936e2f0d211fce685544e/e/80609bd27c501b4e98a1a4f6

Print instructions

Print flat side down with 0% fill, top and bottom concentric. You need to print at least two pieces for test purposes. The included 3mf file will print eight pieces, one at a time (you can edit this to print fewer pieces if you like).