2009/6/11 Rainer Schmidt <[email protected]>: >> I did once have the job of "machining" glass to 0.0001mm but that was >> done with an Ion Mill so doesn't really count.
> .0001mm... can't imagine how steady you have to temper everything > around that thing... How do you position that? Piezo? It actually wasn't difficult in that sense, as it was (thinking back) 100nm +/- 10nm, so actually a very wide relative tolerance on a very tiny thing. I believe that the proposed silicon sphere Avagadro/kg standard is 95mm +/- 30nm, which is a truly impressive bit of manufacturing. http://www.acpo.csiro.au/spheres.htm -- atp ------------------------------------------------------------------------------ Crystal Reports - New Free Runtime and 30 Day Trial Check out the new simplified licensing option that enables unlimited royalty-free distribution of the report engine for externally facing server and web deployment. http://p.sf.net/sfu/businessobjects _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
