This is a model for a 12 mm centerpiece for analytical ultracentrifugation.  The OpenSCAD code has some parameters that allow customization, for example of the pathlength.  Dependent on the material it is printed, which may be carboxylate, acrylics, or metals, gaskets may be required for the use in analytical ultracentrifugation.  With some materials it may be necessary to decrease the diameter by ~0.05 mm or so for a better fit into the aluminum housings. 

For more information see http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0155201 .  For related resources, visit our sharepoint site https://sedfitsedphat.nibib.nih.gov/tools/default.aspx . 

For questions and discussion, join the SEDFIT-L list (https://list.nih.gov/cgi-bin/wa.exe?SUBED1=SEDFIT-L&A=1)