thru hole in tungsten

[vono]

thread281-278396

Does anyone know how Pt or Mo Electron Microscope apertures are made?
as in these

http://www.2spi.com/catalog/apt/disc-apertures.html

I need this in Tungsten but with a single thru hole not stepped.
Thanks

 

[btrueblood]

EDM will do it. If you need a cleaner finish on the hole/edge than edm can provide, then EDM undersize and finish by diamond lap/honing. Same thing as unclesyd proposed lo those many years ago. Also, as he proposed then, contact National Jet in Maryland - they can do rather amazing things.