Here's a how-to guide for collet blocks. This goes along with my indexing lecture for my intermediate machining class at Parkland College.
Print for the 8-sided block: https://drive.google.com/open?id=1Lr9y4HDfFrh4OcZNaZ7tEws0nfJSQj6I
Print for the 10-sided block: https://drive.google.com/open?id=19J0P6sKPEW4qSfSX78je72JNOnPKTPkb