Back to the objects..... Look like plastic extrusion nozzles, although the center hole and the plugs indicate pipe extrusion, the peripheral holes suggest an overwrap of some sort. Would be nice to see back plate. Milling index heads usually have a spiral hole pattern. Clock makers, if any still exsist in this digital age also have specialized jig plates and indexers of same ilk. On May 30, 2017 2:59 AM, "Trevor" wrote: > Sean Breheny wrote on 30/05/2017 15:52: > > Hmmm - but 9FY and 9FF do not occur in that document. 9FG does, but > > it has to do with a sealed DB9 connector, not the item that looks > > like the mystery disks. > > Indeed, I call it serendipity as the cover for the chapter showed more > or less the item under discussion as soon as I opened it :) > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .