What kind of workholding is this?

Image originates from this video by OSG..

The material being cut is PEEK Glass-Fiber 30%. It looks like it's fixtured to a Delrin block some how.. Any ideas on this black magic?

Glue? Threaded from the bottom up?

5 comments

I really doubt this is it, but I worked in a shop where we diced small circles into squares. We used wax to hold them.
- I'm guessing some kind of hard wax? I haven't heard about wax workholding.
  
  Yep. We had 2 kinds. It's been so long I couldn't recall the brands nor why 2 kinds.
I've heard of doing this with PSA (pressure sensitive adhesive). Why? Dunno, kinda strange for anything but esoteric physics devices.

Plus side, no tool crashes. Downside, no physical reference to the machine itself.