Eppendorf test tube rack

thingiverse

I use these when introducing practical biology to students, working closely with a micropipette. This compact Eppendorf test tube rack holds six 10mm tubes in a neat row. Alternatively, by flipping the rack over, you can fit six 8mm tubes snugly inside. Crafted from durable acrylic and secured by four M3 bolts, this design boasts impressive stability. The addition of four M3 x 20mm hexagonal female brass standoffs adds an extra layer of support, ensuring the rack remains steady even during heavy use. As a laser cutter expert myself, I highly recommend this design to those with experience in 3D printing. However, if you're more comfortable working with 3D printers, I believe this design is an excellent choice.